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Flexible and Stable Quantum Dot-PDMS Films via Screen Printing for Photonic Anti-counterfeiting
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作者 LIU Xing HUANG Min +4 位作者 LI Xiu WANG Qiang ZHANG Yuan-kun LI Gen YANG Li-xue 《印刷与数字媒体技术研究》 北大核心 2026年第1期138-146,共9页
Quantum dot(QD)-based fluorescent inks offer high potential due to their tunable emission and high quantum yield,but their practical application suffers from poor environmental stability,aggregation,and challenges in ... Quantum dot(QD)-based fluorescent inks offer high potential due to their tunable emission and high quantum yield,but their practical application suffers from poor environmental stability,aggregation,and challenges in scalable flexible fabrication.In this study,a high-stability fluorescent ink was developed by incorporating QDs into a polydimethylsiloxane(PDMS)colloidal matrix.High-performance patterned films were then obtained via systematic optimization of screen-printing parameters,with film quality governed by substrate type(131μm PDMS),QD concentration(1.5 mg/mL),and screen mesh count(420 mesh).The optimized films exhibit outstanding environmental and photostability,retaining 75.6% of their fluorescence intensity after immersion in deionized water and 63.8% in 75%ethanol at 25℃ for 100 minutes.Under UV irradiation(365 nm,9 W,100 min),fluorescence intensity decreases by less than 20%.Utilizing their daylight transparency and UV-excitable luminescence,various patterns including QR codes and Code 93 standard barcodes were fabricated via screen printing with high pattern fidelity and machine readability.This study presents a scalable and reliable strategy for the fabrication of flexible,high-stability fluorescent films,supporting their integration into next-generation optoelectronic devices,advanced displays,and secure anti-counterfeiting. 展开更多
关键词 Quantum dots Screen printing FLEXIBILITY Optical anti-counterfeiting
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Magnetic Biocompatible Film for Flexible Anti-Counterfeiting and Self-Powered Human Motion Health Monitoring
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作者 Huijing Xiang Chuanzi Deng +5 位作者 Mingxing Cao Jiatong Yan Ning Wang Tiexiang Huang Tong Wu Xia Cao 《Energy & Environmental Materials》 2026年第1期357-367,共11页
Natural polymers possess the qualities of abundant resources,low cost,as well as excellent biocompatibility and biodegradability,and are ideal materials for next-generation wearable and portable electronic devices.To ... Natural polymers possess the qualities of abundant resources,low cost,as well as excellent biocompatibility and biodegradability,and are ideal materials for next-generation wearable and portable electronic devices.To further augment the application scope of natural polymer materials,integrating them with functional materials represents a promising approach that is of great value for the sustainable development of triboelectric nanogenerators.Here,we successfully synthesized starch-[CsPbBr_(3)-KBr]-Fe_(3)O_(4)composite films through the combination of natural polymer materials with magnetic and fluorescent components.It is capable of achieving reversible hydrochromic conversion by exposing or removing water.The combination of fluorescent CsPbBr_(3)-KBr,magnetic Fe_(3)O_(4),and waterproof starch-[CsPbBr_(3)-KBr]-Fe_(3)O_(4)-Polydimethylsiloxane leads to the realization of fluorescence and magnetic composite anti-counterfeiting.This composite anti-counterfeiting technology presents a novel and highly effective approach for ensuring the authenticity and security of various types of information.In addition,the Composite film based triboelectric nanogenerator has been assembled,which has a stable output with a short circuit current and open-circuit voltage of 15.1μA and 170.1 V,respectively.The triboelectric nanogenerator can light 204 red LED lights at the same time,and the electrical output is not reduced even after 4200 mechanical cycles.Furthermore,based on the triboelectric nanogenerator,we have successfully demonstrated a self-powered sensor that can monitor human movement signals in real time.The sensor has shown broad application prospects in the field of health monitoring and motion analysis. 展开更多
关键词 anti-counterfeiting MAGNETIC self-powered sensing triboelectric nanogenerator ULTRAVIOLET
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Highly luminescent all-inorganic lead-free AgInS_(2)/ZnS QDs for multicolor and multistage anti-counterfeiting and encryption
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作者 Pawan Kumar Lei Jin +6 位作者 Gurpreet Singh Selopal Omar Abdelkarim Jiabin Liu David Barba Aycan Yurtsever Zhiming M.Wang Federico Rosei 《Nano Materials Science》 2026年第1期1-10,共10页
We describe the design and synthesis of eco-friendly AgInS_(2)/ZnS QDs via a facile one-pot synthesis method for application in encryption and anti-counterfeiting.A significant enhancement in PLQY(up to 45%)and stabil... We describe the design and synthesis of eco-friendly AgInS_(2)/ZnS QDs via a facile one-pot synthesis method for application in encryption and anti-counterfeiting.A significant enhancement in PLQY(up to 45%)and stability are observed with increased ZnS shell thickness.By varying the Ag:In composition from 1:2 to 1:0.25,the PL emission of AgInS_(2)/ZnS QDs can be tuned from the visible to NIR(up to 900 nm).The ink fabricated with AgInS_(2)/ZnSQDs shows greater thermal and water stability compared to AgInS_(2)QDs.The patterns printed with these luminescent inks show excellent water and thermal stability and the capability to print on surfaces of any type and color,making them promising for practical use.These printed patterns are completely transparent/invisible in normal light and visible under 254 nm,365 nm and 464 nm(blue LED)illumination.These features offer rapid responsive and multi-layered information encryption,and sophisticated anti-counterfeiting. 展开更多
关键词 Quantum dots CORE-SHELL Surface passivation Photoluminescence anti-counterfeiting
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Patterned line-illumination mesoscopy with a moving slit for enhancing background suppression in cortex-wide mouse brain imaging
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作者 Chaowei Zhuang Yi Yang Hao Xie 《Chinese Physics B》 2026年第2期679-684,共6页
Wide-field mesoscopy provides the capabilities of cortex-wide field of view(FOV),cellular resolution and high frame rate for neuronal imaging in the mouse brain.However,inherent background fluorescence degrades the im... Wide-field mesoscopy provides the capabilities of cortex-wide field of view(FOV),cellular resolution and high frame rate for neuronal imaging in the mouse brain.However,inherent background fluorescence degrades the image quality and hinders neuronal signal extraction.To address this problem,we first introduce a cortex-wide,high-resolution lineillumination mesoscope with a moving slit designed for in vivo mouse brain imaging.This system achieves a 6.6×6.6 mm FOV,microscale cellular resolution,a high frame rate of 10 Hz,as well as the background rejection ability.Furthermore,we integrated patterned illumination into the system to enhance the background suppression.Experimental results show that the proposed system successfully captures neurodynamics in the living mouse brain.Compared with conventional wide-field mesoscopes,the cortex-wide patterned line-illumination mesoscope(PLIM)achieves a threefold increase in the signal-to-background ratio(SBR).With patterned illumination integrated,the SBR enhancement further reaches four-anda-half-fold. 展开更多
关键词 wide-field fluorescence imaging optical sectioning patterned illumination
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Developing color-tunable long afterglow anti-counterfeiting materials using cucurbit[6]uril and classical aggregation-caused quenching compounds through multiple non-covalent interactions 被引量:1
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作者 Xingyue Yuan Li Wu +5 位作者 Qiuyu Peng Yanyan Tang Mingxu Wang Yuhang Wei Zhu Tao Xin Xiao 《Chinese Chemical Letters》 2025年第9期345-349,共5页
This investigation focuses on the utilization of cucurbit[6]uril(Q[6])as the host compound for the development of long-lasting afterglow materials.By strategically manipulating the outer surface interactions of Q[6],c... This investigation focuses on the utilization of cucurbit[6]uril(Q[6])as the host compound for the development of long-lasting afterglow materials.By strategically manipulating the outer surface interactions of Q[6],classical aggregation-caused quenching(ACQ)compounds such as fluorescein sodium(FluNa)and calcein sodium(CalNa)were transformed into afterglow materials with varying colors and durations upon exposure to ultraviolet light.This transformation was facilitated through a host-vip doping method combined with coordination with metal ions.Even at a reduced doping concentration of 5×10^(-5)wt%,the materials exhibit remarkable afterglow properties,lasting up to 2 s,with a phosphorescence lifetime of up to 150 ms.Moreover,by adjusting the concentration of the vip compound,the persistent luminescence color of the materials could be easily transitioned from orange to yellow and subsequently to green.These findings suggest that the developed afterglow materials hold significant potential for multilevel anti-counterfeiting and information encryption applications when exposed to ultraviolet light.The supramolecular assembly strategy,which relies on the outer surface interactions of cucurbit[n]uril,offers a simpler and more efficient approach to crafting multi-color luminescent materials.Additionally,this method opens avenues for enhancing the application potential of aggregation-caused quenching(ACQ)compounds in various technological domains. 展开更多
关键词 Cucurbit[n]uril Room-temperature phosphorescence Long afterglow anti-counterfeiting SELF-ASSEMBLY
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Porous Organic Cages with Aggregation-Induced Emission Property for Anti-counterfeiting Ink Bioimaging
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作者 Anli Yang Yifan Guo +6 位作者 Yanji Zhang Zhuolin Yang Yuyo Go Di Wu Chunzheng Ma Linlin Shi Bingjie Li 《Energy & Environmental Materials》 2025年第4期270-277,共8页
The application of aggregation-induced emission(AIE)materials in biological imaging holds multiple significances,including improving detection sensitivity and specificity,optimizing the imaging process,expanding the s... The application of aggregation-induced emission(AIE)materials in biological imaging holds multiple significances,including improving detection sensitivity and specificity,optimizing the imaging process,expanding the scope of application,and promoting advancements in biomedical research.In this work,the propeller ligand was constructed through McMurry coupling reaction and Suzuki coupling reaction by using dimethoxybenzophenone as the starting material.Then,an imine condensation reaction was carried out in chloroform solution,using a 3:2 molar ratio of precursor to tri(2-aminoethyl)amine to synthesize C3 symmetric porous organic cage CB.The structures of the compounds were determined by nuclear magnetic resonance spectroscopy(NMR),electrospray ionization mass spectrometry(ESI-MS)and Fourier transform infrared spectroscopy(FT-IR).The optical investigation results reveal that ligand L-B and the porous organic cage C_(B) demonstrate remarkable aggregation-induced emission(AIE)properties in a tetrahydrofuran/water mixed solvent system,along with a pronounced response to tetrahydrofuran vapor stimuli.Consequently,Furthermore,given its unique cage-like structure,high quantum yield,and outstanding AIE behavior,the porous organic cage C_(B) holds promise for applications in cell imaging. 展开更多
关键词 AIE anti-counterfeiting BIOIMAGING caged-structures
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Multi-mode Polarized Luminescent Au-nanorod Polymer Composites for Advanced Optical Anti-counterfeiting
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作者 Li-Rong Xu Jia-Yong Wang +7 位作者 Jin-Ting Huang Qian-Yi He Shao-Lin Lu Deng-Chong Feng Ze-Tong Ma Zhong-Ke Yuan Yu-Zhao Yang Xu-Dong Chen 《Chinese Journal of Polymer Science》 2025年第11期2118-2127,I0014,共11页
The development of organic afterglow materials with high environmental stability and multi-mode luminescence remains a significant challenge in luminescent anti-counterfeiting.In this work,an organic luminescent molec... The development of organic afterglow materials with high environmental stability and multi-mode luminescence remains a significant challenge in luminescent anti-counterfeiting.In this work,an organic luminescent molecule was encapsulated within polyacrylamide microspheres and embedded in a gold nanorod-doped,ferric ion-crosslinked hydrogel exhibiting upper critical solution temperature behavior.The obtained composites exhibited fluorescence,thermally activated delayed fluorescence,and phosphorescence.Through the application of extrusion or uniaxial stretching,the orientation of the gold nanorods was modulated,enabling polarization-dependent luminescence through transverse surface plasmon resonance absorption.At 300%uniaxial strain,the polarized fluorescence intensity difference at 520 nm reached 0.29.Furthermore,ultraviolet irradiation was employed to locally disrupt the orientation of the gold nanorods,resulting in depolarization within the irradiated regions.These areas displayed non-polarized fluorescence,while the non-irradiated regions retained both emission and fluorescence polarization characteristics.Localized imprinting was employed to modulate material thickness,thereby controlling the density of gold nanorods.Thinner regions exhibited weaker transverse localized surface plasmon resonance absorption,while thicker regions showed stronger absorption,enabling the coexistence of blue–green fluorescence and polarization patterns.Local humidification effectively reduced phosphorescence intensity,enhancing the material's environmental responsiveness.The composite demonstrated excellent reversibility over multiple stretching–selfhealing cycles and pattern-switching processes,highlighting its strong potential for multidimensional optical encryption and intelligent anticounterfeiting applications. 展开更多
关键词 Gold nanorods Hydrogel polymer Polarization anti-counterfeiting Luminescence material
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A Holistic Anti-Counterfeiting Platform Using NFC and Blockchain Technologies
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作者 Rajendren Subramaniam Saaidal Razalli Azzuhri +2 位作者 Teh Ying Wah Atif Mahmood Vimala Balakrishnan 《Computers, Materials & Continua》 2025年第6期4257-4280,共24页
Counterfeiting is still a pervasive global issue,affecting multiple industries and hindering industrial innovation,while causing substantial financial losses,reputational damage,and risks to consumer safety.From luxur... Counterfeiting is still a pervasive global issue,affecting multiple industries and hindering industrial innovation,while causing substantial financial losses,reputational damage,and risks to consumer safety.From luxury goods and pharmaceuticals to electronics and automotive parts,counterfeit products infiltrate supply chains,leading to a loss of revenue for legitimate businesses and undermining consumer trust.Traditional anti-counterfeiting measures,such as holograms,serial numbers,and barcodes,have proven to be insufficient as counterfeiters continuously develop more sophisticated replication techniques.As a result,there is a growing need for more advanced,secure,and reliable methods to prevent counterfeiting.This paper presents a novel,holistic anti-counterfeiting platform that integrates Near Field Communication(NFC)-enabled mobile applications with blockchain technology to provide an innovative,secure,and consumer-friendly authentication mechanism.Our approach addresses key gaps in existing solutions by incorporating dynamic product identifiers,which make replication significantly more difficult.The system enables consumers to verify the authenticity of products instantly using their smartphones,enhancing transparency and trust in the supply chain.Blockchain technology plays a crucial role in our proposed solution by providing an immutable,decentralized ledger that records product authentication data.This ensures that product verification records cannot be tampered with or altered,adding a layer of security that is absent in conventional systems.Additionally,NFC technology enhances security by offering unique identification capabilities,enabling real-time product verification.To validate the effectiveness of the proposed system,real-world testing was conducted across different industries.The results demonstrated the platform’s ability to significantly reduce counterfeit products in the supply chain,offering businesses and consumers a more robust and reliable authentication method.By leveraging the combined strengths of blockchain and NFC,this solution represents a significant advancement in the fight against counterfeiting,ensuring enhanced security,transparency,and consumer trust. 展开更多
关键词 Blockchain near field communication(NFC) anti-counterfeiting
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Thermochromic luminescence in low-dimensional antimony hallide for detection of trace amount of water and anti-counterfeiting
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作者 Hong-Zhao Zan Hai-Xin Zhao +7 位作者 Xi-Gui Gao Xiao-Zhong Wang Yun-Zhi Zhu Guo-Kun Li Xu-Yang Yao Chen Li Xiang-Wen Kong Xiao-Wu Lei 《Chinese Journal of Structural Chemistry》 2025年第12期23-31,共9页
Stimuli-responsive luminescent switching materials with multifunctional properties are highly essential for advanced photonic applications,yet achieving such capabilities in halide perovskites continues to pose a sign... Stimuli-responsive luminescent switching materials with multifunctional properties are highly essential for advanced photonic applications,yet achieving such capabilities in halide perovskites continues to pose a signif-icant challenge.In this work,we explore a new water-stimuli-responsive zero-dimensional(0D)Sb-based halide of[PhPz]_(2)SbCl_(7)·2H_(2)O(PhPz=phenylpiperazine),which consists of isolated[SbCl_(6)]^(3-) octahedra in[PhPz]2+cationic matrix with vip H_(2)O molecules.Under UV excitation,[PhPz]_(2)SbCl_(7)·2H_(2)O emits intense broadband red light with maximum emission at 645 nm,and combined optical characterization and theoretical calculations confirm that this luminescence originates from self-trapped excitons(STEs).Interestingly,the free water molecules can reversibly leave and entry the crystal lattice during heating-cooling cycles accompanied by the formation of dehydrated phase,which displays strong yellow emission with maximum peak at 580 nm.Therefore,reversible luminescent switching between red and yellow emission is achieved through controllable removal and adsorption process of vip H_(2)O.By virtue of this reversible thermochromic switching,this halide can be used to detect the trace amount of water in various organic solvents and humidity of moist air.In addition,such switchable dual emission further realizes application in anti-counterfeiting and information encryption-decryption.This work deepens the understanding of structure-property relationships and expands the application range of oD metal halides. 展开更多
关键词 Hybrid metal halide Smart luminescent material THERMOCHROMISM Water detection anti-counterfeiting
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Unanticipated optical properties of π-conjugated cyclometalated Pt(Ⅱ)complexes for advanced information storage and anti-counterfeiting materials
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作者 Yinghao Zhang Ke Shao +5 位作者 Yihang Zhu Haokun Zhang Yinuo Zhuo Huihui Bao Yeye Ai Yongguang Li 《Chinese Chemical Letters》 2025年第9期434-438,共5页
In this work,we synthesize two luminescent Pt(Ⅱ)complexes using differentπ-conjugated bidentate ligands.Both complexes are assembled into three-dimensional(3D)networks through non-classical intermolecular interactio... In this work,we synthesize two luminescent Pt(Ⅱ)complexes using differentπ-conjugated bidentate ligands.Both complexes are assembled into three-dimensional(3D)networks through non-classical intermolecular interactions in the crystal state.Unexpectedly,substituting pyridine with the more extensivelyπ-conjugated quinoline significantly increases the dihedral angles between the phenyl and quinolyl groups of the bidentate ligands.This alteration disrupts theπ-πinteractions between molecules,resulting in distinct optical properties upon exposure to external stimuli.By integrating these complexes into polymers,we fabricate electrospun films containing luminescent nanofibers that exhibit reversible optical changes.These findings have paved the way for the development of high-performance optical encryption and anti-counterfeiting materials,achieved through the employment of simple chromophores. 展开更多
关键词 Pt(Ⅱ)complexes Electrospun film anti-counterfeiting material THERMOCHROMISM Mechanochromism
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Dual-band-tunable all-inorganic Zn-based metal halides for optical anti-counterfeiting
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作者 Meng Wang Dehai Liang +3 位作者 Saif M.H.Qaid Shuangyi Zhao Yingjie Liu Zhigang Zang 《Opto-Electronic Advances》 2025年第10期30-39,共10页
Low-dimensional lead-free metal halides have emerged as promising candidates for anti-counterfeiting applications,characterized by their low toxicity,diverse crystal structures,and exceptional optical properties.Conve... Low-dimensional lead-free metal halides have emerged as promising candidates for anti-counterfeiting applications,characterized by their low toxicity,diverse crystal structures,and exceptional optical properties.Conventional anti-counterfeiting technologies based on low-dimensional metal halides are often constrained by complex and time-consuming heating and solvent treatments that may insufficiently modify the luminescent characteristics of emitters,thus hindering their practical implementation in effective anti-counterfeiting strategies.In this study,we employ an innovative alloying strategy in low-dimensional zinc halides Cs_(2)ZnCl_(4) to enhance their luminescent performance.By introducing self-trapped exciton(STE)states through the alloying of Cu^(+)and Sb^(3+)ions in Cs_(2)ZnCl_(4),we achieve bright blue and red photoluminescence(PL)centered at 492 nm and 744 nm,respectively,under 266 nm excitation,with only red emission observed under 365 nm excitation.This approach enables instant and reliable anti-counterfeiting applications.This work presents new opportunities for developing robust anti-counterfeiting and information encryption/decryption technologies. 展开更多
关键词 Zn-based metal halides dual-band emission optical anti-counterfeiting Cu^(+)and Sb^(3+)doping
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Adaptive beam-shaping enabled high-precision patterned laser micro-grooving
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作者 Pei Qiu Jun Li +3 位作者 Dandan Yuan Zixuan Xin Jiaxu Huang Shaolin Xu 《International Journal of Extreme Manufacturing》 2025年第6期390-402,共13页
Microgrooves with diverse cross-sections are required in various fields but remain a significant challenge in precision machining,especially for hard-to-machine materials.Patterned laser ablation offers an avenue for ... Microgrooves with diverse cross-sections are required in various fields but remain a significant challenge in precision machining,especially for hard-to-machine materials.Patterned laser ablation offers an avenue for fabricating microgrooves on any material with notably enhanced shape diversity.However,it is hard to precisely control the grooves'cross-sectional profiles due to the complex ablation process,including the diffraction-induced energy distribution variations away from the focal plane and the inconsistent polarization-related energy absorption.These factors complicate the relationship between beam spot shape and ablated groove shape,making it challenging to design appropriate spot shapes for specific groove requirements.Here,we propose an adaptive beam-shaping method for laser spot design to improve microgrooves'shape accuracy.Combining laser diffraction and polarization effects,a profile evolution model of the laser ablation is established to accurately predict groove shapes,guiding the iterative beam-shaping procedure.The beam spot shape is iteratively fine-tuned until the deviation between the simulated and the target grooves'profile meets the accuracy requirements.The grooves'profile deviations are significantly reduced,with the final profile's root mean square error decreased to less than 0.5μm when processing microgrooves with a width of 10μm.Various microgrooves with precise cross-sections,including triangles,trapezoids,and functionally contoured micro structures,are achieved by patterned laser direct writing assisted with the adaptive beam-shaping method.This method paves the way for laser ablation of microgrooves with high shape accuracy for traditional hard-to-machine materials. 展开更多
关键词 laser ablation patterned laser adaptive beam-shaping ablation profile evolution MICROGROOVES
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3D Printed PEDOT:PSS Flexible Electrochromic Devices for Patterned Displays
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作者 Manting Song Changchen Gong Ximei Liu 《Journal of Polymer Materials》 2025年第1期111-123,共13页
Flexible electrochromic devices(FECDs)demonstrate significant potential for applications in wearable elec-tronics,military camouflage,and flexible smart displays.As a crucial electrochromic material,poly(3,4-ethylened... Flexible electrochromic devices(FECDs)demonstrate significant potential for applications in wearable elec-tronics,military camouflage,and flexible smart displays.As a crucial electrochromic material,poly(3,4-ethylenedioxythiophene):polystyrene sulfonate(PEDOT:PSS)is widely used in FECDs due to its excellent mechanical flexibility,tunable conductivity,and non-toxicity.However,the manufacturing process for patterned PEDOT:PSS electrochromic devices remains intricate,costly,and challenging to personalize.To address this challenge,we have developed a 3D-printable ink with controllable rheological properties through a concentration-tuning strategy,enabling programmable,patterned printing of PEDOT-based conductive polymer electrochromic layers.The 3D-printed FECDs exhibit outstanding electrochromic performance,including a high optical contrast(up to 47.9%at 635 nm),fast response times(t_(c)=1.6 s;t_(b)=0.6 s),high coloration efficiency(352 cm^(2) C^(-1)),and good cycling stability(with only a 9.3%decrease in optical contrast after 100 electrochemical cycles).Finally,we utilize 3D printing technology to construct flexible,patterned PEDOT:PSS electrochromic devices with bespoke butterfly designs.This work establishes the theoretical foundation for the application of 3D printing technology in PEDOT:PSS flexible electrochromic devices. 展开更多
关键词 3D printing PEDOT:PSS flexible electrochromic device patterned displays
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Luminescence enhancement effects of Ca_(x)Sr_(2-x)Nb_(2)O_(7):Er^(3+),Tm^(3+) phosphors for temperature sensing and anti-counterfeiting applications
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作者 Wenchao Chen Huabo Gao +5 位作者 Maxim S.Molokeev Qi Chen Xiangpeng Geng Lefu Mei Xin Min Bin Ma 《Journal of Rare Earths》 2025年第7期1345-1354,共10页
Er^(3+)-and Tm^(3+)-doped Ca_(x)Sr_(2-x)Nb_(2)O_(7)(C_(x)S_(2-x)N,x=0.6,0.8,1,0,1.2,1,4) phosphors with layered pe rovskite structure were designed.These phosphors exhibit a dominant emission peak at 549 nm under980 n... Er^(3+)-and Tm^(3+)-doped Ca_(x)Sr_(2-x)Nb_(2)O_(7)(C_(x)S_(2-x)N,x=0.6,0.8,1,0,1.2,1,4) phosphors with layered pe rovskite structure were designed.These phosphors exhibit a dominant emission peak at 549 nm under980 nm laser excitation,attributed to the^(4)S_(3/2)→^(4)I_(15/2)transition.By increasing the content of Ca^(2+),the crystal field regulation of rare earth ions is realized and the luminescence enhancement is induced,which is manifested by the increase of^(2)H_(11/2),^(4)S_(3/2)→^(4)I_(15/2)emission.Furthermore,the temperature sensing sensitivities of C_(0.6)S_(1.4)N:Er,Tm and C_(0.6)S_(1.4)N:Er,Tm based on non-thermally coupled energy levels were studied.Finally,an anti-counterfeiting imprint was prepared using phosphors,which have high brightness and excellent photothermal stability.This work not only confirms that closer ionic radii substitution enables to increase the electronic density of states,improve the crystal field symmetry and enhance the luminescence,but also provides a promising phosphor system for temperature sensing and anti-counterfeiting applications,opening up new prospects in the optimization of the optical properties of phosphors. 展开更多
关键词 Ca_(x)Sr_(2-x)Nb_(2)O_(7):Er Tm phosphor Luminescence enhancement Crystal field Temperature sensing anti-counterfeiting Rare earths
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Seasonal emission patterns of airborne phytoncides in temperate forests from autumn to early spring:a case study of Xishui National Forest Park(Yichun,Northeast China)
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作者 Hongda Cai Yitong Wang +6 位作者 Xianwen Huang Sen Zhang Yankun Liu Jian Zhang Dongmei Zhao Peng Zhao Xiuhua Zhao 《Journal of Forestry Research》 2026年第1期256-271,共16页
Xishui National Forest Park in Heilongjiang Province hosts China's most pristine temperate forests and serves as a key site for ecotourism and forest therapy.However,the emission patterns of phytoncides(key bio ac... Xishui National Forest Park in Heilongjiang Province hosts China's most pristine temperate forests and serves as a key site for ecotourism and forest therapy.However,the emission patterns of phytoncides(key bio active compounds) remain poorly understood,limiting their therapeutic application.This study provides the first comprehensive characterization of spatiotemporal dynamics in airborne phytoncides and their synergistic interactions with environmental factors throughout the autumn-early spring seasonal transition in a temperate forest ecosystem.We analyzed the compositional dynamics of phytoncides and terpenoid content variations using thermal desorption-gas chromatography-mass spectrometry(TD-GC-MS) from September 2024 to March 2025.This period encompassed seasonal transitions from autumn to early spring,including diurnal variations in September and snowfall events in November.The method demonstrated detection limits(LODs) ranging from 1.35 to 5.33 ng m-3 and quantification limits(LOQs) from 4.09 to 16.15 ng m-3.Our results revealed pronounced seasonal fluctuations in phytoncide composition.In September,terpenoids,esters,alcohols,and alkanes displayed a diurnal "decrease-increase" trend,whereas aldehydes and ketones peaked at midday.Notably,esters and alcohols were undetectable in November and January.By January,terpenoids reached their lowest proportion(0.17±0.02%) at noon.Five terpenoids(α-pinene,myrcene,D-limonene,camphene,p-cymene) were detected in September,four(α-pinene,D-limonene,camphene,p-cymene) in November,two(D-limonene,p-cymene) in January,and only p-cymene in March.The total concentration and emission rate of the five terpenoids peaked in September afternoons at 1961.58±106.67 ng m^(-3) and653.86±35.56 ng m^(-3) h^(-1),respectively.Nocturnal emissions(32131.95±2522.21 ng m^(-3)) significantly surpassed daytime levels(14473.04±958.49 ng m^(-3)),with emission rates escalating from 1447.30±95.85 ng m^(-3) h^(-1)(day) to 5355.33±420.37 ng m^(-3) h^(-1)(night),marking a3.7-fold increase.Snowfall dramatically elevated terpenoid concentrations(pre-snowfall:158.58±14.12 ng m^(-3);post-snowfall:1080.57±57.76 ng m^(-3)) and emission rates(pre-snowfall:52.86±4.71 ng m^(-3) h^(-1);post-snowfall:360.19±19.25 ng m^(-3) h^(-1)),reflecting a 6.8-fold surge.This study underscores the profound influence of light intensity,seasonal shifts,and climatic conditions on airborne phytoncide levels,offering a scientific foundation for optimizing forest therapy and ecotourism strategies. 展开更多
关键词 Phytoncides Seasonal variation Diurnal-nocturnal patterns Snowfall impact Emission patterns
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Incorporating multiple scenarios and landscape ecological risk to optimize ecological security patterns: A Wei River Basin case study
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作者 Xueting Wu Jinghu Pan 《Chinese Journal of Population,Resources and Environment》 2026年第1期94-109,共16页
Under the influence of human activities,landscape fragmentation in the Wei River Basin(WRB)has become increasingly severe.Upstream development has intensified soil erosion,and industrial and agricultural pollution in ... Under the influence of human activities,landscape fragmentation in the Wei River Basin(WRB)has become increasingly severe.Upstream development has intensified soil erosion,and industrial and agricultural pollution in the middle reaches has degraded water quality.Rapid urbanization has further caused habitat fragmentation and biodiversity loss.Collectively,these challenges threaten human well-being and hinder sustainable development,making the construction and optimization of an ecological security pattern(ESP)urgently necessary.However,existing studies often fail to systematically integrate future landscape ecological risk(LER)assessment with ESP optimization.This study evaluated regional LER using the“ecological patches-ecological resistance surface(ERS)-ecological corridor”framework,combined with land-use predictions under three development scenarios,and optimized the ESP by adjusting the ERS and extracting ecological corridors.The results indicate that the LER in the WRB follows an“inverted N”distribution,with low-risk areas concentrated in forested mountain regions and high-risk areas mainly in cultivated land subject to intensive human activity.Across future scenarios,ESPs showed fewer ecological breakpoints and improved landscape connectivity than the 2020 baseline.Scenario-based differences emerged in the spatial configuration of ERS adjustments,with the ecological protection scenario yielding the lowest LER and most favorable ESP.This study demonstrates the deep integration of multi-scenario simulation with LER assessment,providing a new framework for ESP optimization.The findings have guiding significance for ecological protection and coordinated development in the WRB and offer a novel paradigm for sustainable development in ecologically fragile basins worldwide. 展开更多
关键词 Ecological security pattern Multiple scenarios Landscape ecological risk Ecological security pattern optimization
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Thoughts on the scientific research of the connotation of traditional Chinese medicine patterns
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作者 Kang Xie Yulin Ouyang +1 位作者 Yong Wang Chun Li 《Journal of Traditional Chinese Medical Sciences》 2026年第1期3-11,共9页
Traditional Chinese medicine(TCM)is a holistic medical system that classifies and treats diseases based on the concept of patterns.These patterns describe the pathophysiological process of a disease at a specific stag... Traditional Chinese medicine(TCM)is a holistic medical system that classifies and treats diseases based on the concept of patterns.These patterns describe the pathophysiological process of a disease at a specific stage,reflecting both external signs and internal features.TCM patterns are central to pattern differentiation,treatment,clinical practice,and theoretical development in TCM.However,scientific explanation of TCM patterns remains limited because of subjective diagnostic criteria,the absence of a standardized experimental medical system,and unclear biological mechanisms,which restrict the modernization and globalization of TCM.Addressing challenges such as strong subjectivity in diagnosis,lack of standardized experimental systems,and unclear biological mechanisms is necessary to clarify the scientific meaning of TCM patterns and to provide technical approaches for the modernization and globalization of TCM.A strategy focused on“pathogenic factors,genetic predisposition,and disease progression stages”was adopted.This approach included the following:(Ⅰ)constructing disease-pattern integrated biological models with animal models,organoids,and multi-organ chips;(Ⅱ)applying multi-omics technologies,such as spatial omics,single-cell omics,and dynamic metabolic flux omics;(Ⅲ)using artificial intelligence(AI)and big data for data integration and prediction of pattern evolution;and(Ⅳ)validating formula–pattern associations through the“pattern differentiation through formula efficacy”approach.These strategies directly address the main obstacles in TCM pattern research by providing objective,quantifiable,and reproducible methodologies.Constructing disease-pattern integrated models enabled cross-scale research platforms.Applying multi-omics technologies allowed analysis of complex biological bases.AI and big data approaches addressed challenges related to heterogeneous data.The“formula-based pattern differentiation”approach supported precise interventions and the development of new drugs.This interdisciplinary framework advances TCM pattern research by moving from empirical description to objective quantification.By integrating innovative approaches,the study establishes a foundation for systematic,evidence-based TCM diagnosis and treatment,supporting accuracy and promoting international recognition and modernization of TCM.The study shows that combining multi-omics technologies,AI-driven data analysis,and disease-pattern models enables objective quantification of TCM patterns and clarifies their biological mechanisms. 展开更多
关键词 Traditional Chinese medicine patterns Disease-pattern integrated model Multi-omics technology Artificial intelligence pattern differentiation through formula efficacy
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Species Diversity and Elevational Patterns of Reptiles in the Leigongshan National Nature Reserve, Guizhou Province, China
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作者 Xue GOU Caichun PENG +7 位作者 Tuo SHEN Chaobo FENG Lang MU Jing LIU Haijun SU Xiujun TANG Shize LI Xingui LI 《Asian Herpetological Research》 2026年第1期31-33,共3页
Dear Editor,Understanding patterns of species diversity is a primary research focus in macroecology,with its distribution patterns having been described and theoretically validated on a global scale(Peters et al.,2016... Dear Editor,Understanding patterns of species diversity is a primary research focus in macroecology,with its distribution patterns having been described and theoretically validated on a global scale(Peters et al.,2016;Sonne et al.,2025).Numerous studies have found that species richness of different taxa tends to decrease with increasing elevation and is modulated by latitudinal gradients(Peters et al.,2016;Dolson et al.,2024).This principle provides a crucial scientific basis for regional conservation planning.However,it still exhibits significant variations across different mountain ranges and taxa. 展开更多
关键词 patterns species diversity Leigongshan National Nature Reserve species richness Guizhou Province reptiles species diversity elevational patterns regional conservation plannin
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Variation in vegetation characteristics and landscape patterns of urban forests:implications for ecosystem management under rapid urbanization
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作者 Jialin Zhong Jiamei Tu +5 位作者 Xin Li Yao Fu Wei Liu Foyi Zhang Shuyang Hu Qiong Wang 《Journal of Forestry Research》 2026年第2期224-238,共15页
Urban forests are essential components of green infrastructure,however,rapid urbanization-induced changes in landscape patterns may affect their ecosystem services through complex ecological processes.A total of 184 s... Urban forests are essential components of green infrastructure,however,rapid urbanization-induced changes in landscape patterns may affect their ecosystem services through complex ecological processes.A total of 184 sample plots in the built-up areas of Nanchang,China,were used as research sites.Urbanization intensities were categorized by the rate of impervious surface area,and forest types were classified into landscape and relaxation forest,attached forest(AF),road forest(RF),and ecological public welfare forest.This study aimed to explore the spatial variations in vegetation characteristics and landscape pattern indices of different forest types under rapid urbanization.The results indicated that the largest patch index(LPI),aggregation index(AI),and percentage of landscape(PLAND)in RF and AF were lower than those in the other forest types(p<0.05).With increasing urbanization intensity,the mean perimeter-area ratio increased by 130.84%,whereas the PLAND,LPI,and AI decreased by 22−86%(p<0.05).Redundancy analysis and variation partitioning suggested that the interpretation rate of landscape pattern indices for variations in vegetation characteristics increased from low to heavy urbanization areas.Especially,the landscape shape index,patch connection index,PLAND,and mean patch size were significantly correlated with vegetation characteristics(e.g.,tree richness,herb coverage,and tree height).In the future,appropriate landscape layout superiority cases should be considered in different urbanization areas and forest types;for instance,increasing the patch connection index will beneficially improve the diversity of trees and herbs in heavy urbanization areas and the RF.This study serves as a reference for maximizing the ecosystem services of urban forests. 展开更多
关键词 Forest type VEGETATION URBANIZATION Landscape pattern
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Improving Online Restore Performance of Backup Storage via Historical File Access Pattern
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作者 Ruidong Chen Guopeng Wang +5 位作者 Jingyuan Yang Ziyu Wang Fang Zou Jia Sun Xingpeng Tang Ting Chen 《Computers, Materials & Continua》 2026年第3期1536-1558,共23页
The performance of data restore is one of the key indicators of user experience for backup storage systems.Compared to the traditional offline restore process,online restore reduces downtime during backup restoration,... The performance of data restore is one of the key indicators of user experience for backup storage systems.Compared to the traditional offline restore process,online restore reduces downtime during backup restoration,allowing users to operate on already restored files while other files are still being restored.This approach improves availability during restoration tasks but suffers from a critical limitation:inconsistencies between the access sequence and the restore sequence.In many cases,the file a user needs to access at a given moment may not yet be restored,resulting in significant delays and poor user experience.To this end,we present Histore,which builds on the user’s historical access sequence to schedule the restore sequence,in order to reduce users’access delayed time.Histore includes three restore approaches:(i)the frequency-based approach,which restores files based on historical file access frequencies and prioritizes ensuring the availability of frequently accessed files;(ii)the graph-based approach,which preferentially restores the frequently accessed files as well as their correlated files based on historical access patterns,and(iii)the trie-based approach,which restores particular files based on both users’real-time and historical access patterns to deduce and restore the files to be accessed in the near future.We implement a prototype of Histore and evaluate its performance from multiple perspectives.Trace-driven experiments on two datasets show that Histore significantly reduces users’delay time by 4-700×with only 1.0%-14.5%additional performance overhead. 展开更多
关键词 Online restore access pattern correlation graph TRIE
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