Counterfeiting is one of the most serious problems in the consumer market. One promising approach for anti-counterfeiting is to attach a low-cost Radio-frequency Identification (RFID) tag to the product authentication...Counterfeiting is one of the most serious problems in the consumer market. One promising approach for anti-counterfeiting is to attach a low-cost Radio-frequency Identification (RFID) tag to the product authentication. In this paper, we propose an RFID system for detecting counterfeiting products. This RFID system consists of the tag authentication protocol and the database correction protocol. We use the tag authentication protocol for authenticating tags without revealing their sensitive information. This protocol also allows the customer to freely inquire the tag. To prevent the widespread of the counterfeit products, we use the tag status information along with tag identity information. Meanwhile, the database correction protocol guarantees the correctness of the tag status. Our anti-counterfeiting system is the first work considering the seller who plays an important role in the consumer product supply chain. Finally, we show that anti-counterfeiting system is quite secure against counterfeiting and the tag authentication protocol is lightweight enough to be implemented in RFID-based applications.展开更多
Novel hydrophilic NaYF4:Yb^3+,Tm^3+@NaGdF4:Ce^3+,Eu^3+double-jacket microtubes(DJMTs)with upconversion/downconversion dual-mode luminescence were designed and prepared through epitaxial growth of NaGdF4:Ce^3+,Eu^3+she...Novel hydrophilic NaYF4:Yb^3+,Tm^3+@NaGdF4:Ce^3+,Eu^3+double-jacket microtubes(DJMTs)with upconversion/downconversion dual-mode luminescence were designed and prepared through epitaxial growth of NaGdF4:Ce^3+,Eu^3+shell onto the NaYF4:Yb^3+,Tm^3+microtube via poly(acrylic acid)(PAA)mediated hydrothermal method.It is demonstrated that PAA ligand played an important role in guiding the direct growth of NaGdF4:Ce^3+,Eu^3+shell onto the surface of NaYF4:Yb^3+,Tm^3+parent microtubes.The growth of NaGdF4:Ce^3+,Eu^3+shell experienced a crystal phase transition fromβ-NaGdF4 andβ-NaYF4 mixture toβ-NaYF4@NaGdF4 composite crystal,and morphology evolution from mixture ofβ-NaGdF4:Ce^3+,Eu^3+nanorods andβ-NaYF4:Yb^3+,Tm^3+microtubes to NaYF4:Yb^3+,Tm^3+@NaGdF4:Ce^3+,Eu^3+DJMTs.The formation mechanism of DJMTs was the dissolution−renucleation ofβ-NaGdF4:Ce^3+,Eu^3+nanorods and the growth ofβ-NaGdF4:Ce^3+,Eu^3+shell via the classical Ostwald ripening mechanism.The as-prepared DJMTs could exhibit blue upconversion and red downconversion luminescence,which was further made into environmentally benign luminescent inks for creating highly secured and fluorescent-based anti-counterfeiting patterns via inkjet printing.展开更多
Pharmaceutical counterfeiting is a health scourge responsible for several cases of morbidity and mortality. Counterfeit medicines cause therapeutic failure, emergence of resistance in the treatment of infections. This...Pharmaceutical counterfeiting is a health scourge responsible for several cases of morbidity and mortality. Counterfeit medicines cause therapeutic failure, emergence of resistance in the treatment of infections. This study was conducted in order to identify counterfeit and authentic medicines in circulation in Lubumbashi. The study included artemether and artesunate for oral administration. A careful visual inspection of medicine, investigation of authenticity of pharmaceutical products from manufacturers and pharmaceutical regulatory authorities and determination of content were used as study parameters. 52 samples: 37 artemether and 15 of artésunate were collected. 7 samples (13%) have proven to be counterfeit. Artemether was the most counterfeit (71%) and 29% for artesunate. 6 (12%) samples were substandard according to the international pharmacopoeia in terms of content of active ingredient. Sixty-seven percent of non-compliance concerned counterfeit medicines. The proportion of non-compliance is highest among counterfeit medicines (71.43% vs 2.22%;p = 0.000004). It is obvious that strengthening the capacity of the drug regulatory authority of the DRC reduces the influx of counterfeit drug and substandard.展开更多
February-15,virtual ITU is organizing a series of webinars on Combating counterfeiting and stolen information and communications technology(ICT)devices.The Episode 1:"Existing challenges and solutions on combatin...February-15,virtual ITU is organizing a series of webinars on Combating counterfeiting and stolen information and communications technology(ICT)devices.The Episode 1:"Existing challenges and solutions on combating counterfeiting of ICT devices",will take place fully virtually on 15 February 2023.展开更多
Highly ordered films of polystyrene(PS)micro-spheres have demonstrated various merits in optoelectronic devices,given their size-and thickness-dependent optical properties.So far,various solution strategies have been ...Highly ordered films of polystyrene(PS)micro-spheres have demonstrated various merits in optoelectronic devices,given their size-and thickness-dependent optical properties.So far,various solution strategies have been developed for making such highly ordered films,which have suffered from the lack of precise control on the film thickness(i.e.,layer number of micro-spheres).Here,we developed a facile fibrous liquid bridge strategy for fabricating highly ordered PS micro-sphere films,featured as the finely tunable mono-to multi-layer.Guided by a horizontally placed fiber with both ends passing through a capillary tube,respectively,the solution was transferred steadily onto the target substrate forming a homogeneous liquid film,whose dewetting process thus confines the assembly ofmicro-spheres in a well-controllablemanner.Depending on both the solution-shearing speed and the local concentration,a dynamic equilibrium between liquid transfer and evaporation was realized,which enables the formation of highly ordered micro-sphere films with finely tunable layer numbers.We demonstrated the angle-specific information encryption for anti-counterfeiting by utilizing patterned PS micro-sphere films that modulate structural colors based on layer-dependent optical responses.The result offers a new perspective for fabricating highly ordered film with tunable layers.展开更多
Lanthanide-based luminescent anticounterfeiting materials are widely used in various kinds of products.At present,the conventional lanthanide-based luminescent anticounterfeiting technique is based on photoluminescenc...Lanthanide-based luminescent anticounterfeiting materials are widely used in various kinds of products.At present,the conventional lanthanide-based luminescent anticounterfeiting technique is based on photoluminescence from ultraviolet light irradiation,resulting in the decreased efficiency of anticounterfeiting applications.In this work,we realized three luminescence modes in a perovskite structure(CaTiO_(3):Pr^(3+),Er^(3+)),in which the excitation-wavelength-dependent photoluminescence(PL)emission,afterglow and upconversion luminescence(UCL)of a doped lanthanide were first presented.Upon ultraviolet excitation,the color of the PL emission can be finely tuned from red to orange,yellow and green by increasing the excitation wavelength from 365 nm to 380 nm.The doped lanthanide emits an intense green color upon illumination with a 980 nm excitation source and a long persisting red color(612 nm)when a UV lamp at 365 nm excitation is switched off.Based on the above luminescence modes of CaTiO_(3):Pr^(3+),Er^(3+),a multilevel anticounterfeiting quick response code(QR code)was developed.The QR code readily integrates the advantages of the excitation wavelength-dependent PL emissions,a strong red afterglow and sensitive excitation power-dependent UCL emissions in one overall device.The presented multilevel anticounterfeiting strategies may inspire the resolution of counterfeit issues in various fields.展开更多
To understand the fundamental mechanism of aggregation-induced phosphorescent emission(AIPE)and to improve the development of mechanochromic molecules,five new Pt(II)complexes Pt-1–Pt-5 bearing different terminal sub...To understand the fundamental mechanism of aggregation-induced phosphorescent emission(AIPE)and to improve the development of mechanochromic molecules,five new Pt(II)complexes Pt-1–Pt-5 bearing different terminal substituents on 1,3-di(2-pyridyl)benzene(N^C^N)ligands were designed and synthesized.Their photophysical properties have been investigated systematically via a series of spectroscopic methods.Upon excitation,the solid states of these Pt complexes exhibit tunable emissions from yellow to red,and complexes Pt-2 and Pt-3 with a large steric hindrance display remarkable AIPE properties in a tetrahydrofuran/H_(2)O mixture.All complexes,except Pt-5,show evident mechanochromic and vapochromic behaviors.Based on in-depth experimental studies,the reason for the mechanochromic behavior could be the change in the distance of the neighboring Pt complexes,which causes a switching of the emission state from^(3)π,π*/^(3)MLCT(metal-to-ligand charge transfer)to^(3)MLCT.The above results suggest an example of phosphorescence tuning by a switching of the triplet excited state in the solid state,and provide a mechanism of mechanochromic behavior.Furthermore,complex Pt-2 was used as an emission ink in the field of advanced anti-counterfeiting.展开更多
Here,multimodal fluorescent materials of Ca_(3)Al_(2)Ge_(3)O_(12):Mn^(2+),Cr^(3+)were synthesized by the traditional high-temperature solid-state reaction method.In this garnet Ca_(3)Al_(2)Ge_(3)O_(12) structure,Mn^(2...Here,multimodal fluorescent materials of Ca_(3)Al_(2)Ge_(3)O_(12):Mn^(2+),Cr^(3+)were synthesized by the traditional high-temperature solid-state reaction method.In this garnet Ca_(3)Al_(2)Ge_(3)O_(12) structure,Mn^(2+)and Cr^(3+)ions occupy dodecahedral sites(Ca sites)and hexahedral sites(Al sites),and can produce dynamic colortunable persistent luminescence at different concentrations,different excitations,and different temperatures;in particular,continuous luminescence with temperature(300 K–473 K)shows a color change from green to deep red.Through detailed pyrolysis studies and theoretical calculations,it is demonstrated that the double-trap structure existing in the host makes the persistent luminescence color temperaturedependent.Anti-counterfeiting and industrial inspection molds were successfully accomplished,which means Ca_(3)Al_(2)Ge_(3)O_(12):Mn^(2+),Cr^(3+)may be used in anti-counterfeiting and industrial inspection.展开更多
Advanced anti-counterfeiting materials have great research significance in the fields of economy,safety and human health.Compared with independent color mixed anti-counterfeiting materials,ultraviolet(UV)excitation wa...Advanced anti-counterfeiting materials have great research significance in the fields of economy,safety and human health.Compared with independent color mixed anti-counterfeiting materials,ultraviolet(UV)excitation wavelength-dependent discoloration,which can realize the change of the emission peak shape and color under different excitation wavelengths,is more attractive.展开更多
Recently,persistent luminescence materials(PLMs)have attracted extensive attention in the anti-counterfeiting and information encryption fields.Unfortunately,single visible persistent luminescence(PersL)demonstrates l...Recently,persistent luminescence materials(PLMs)have attracted extensive attention in the anti-counterfeiting and information encryption fields.Unfortunately,single visible persistent luminescence(PersL)demonstrates limited information security because the changes in information coded by visible PersL can be observed by the human eyes.In this work,we develop a dual-mode PLM with ultraviolet(UV)and visible PersL.展开更多
Persistent luminescent phosphors(PLPs)have attracted much attention in anti-counterfeiting,biosensing and bioimaging due to their characteristic properties of emitting long persistent luminescence(PersL)after excitati...Persistent luminescent phosphors(PLPs)have attracted much attention in anti-counterfeiting,biosensing and bioimaging due to their characteristic properties of emitting long persistent luminescence(PersL)after excitation ceases.However,most of the PLPs developed so far have only one PersL emission peak,which limits their application in advanced anti-counterfeiting and precise biosensing.Here,a series of dual-emissive Zn_(2)GeO_(4):x%Tb^(3+)/y%Bi^(3+)PLPs was prepared by codoping Tb^(3+)ions and Bi^(3+)ions to significantly improve the trap depth and trap density,resulting in a 16.8-fold increase in PersL intensity compared to the Zn_(2)GeO_(4) host.The photoluminescence(PL)color was adjusted to pale blue under 254 nm UV excitation by trap depth engineering,while the PersL color was green,and the PL color under 365 nm UV excitation was yellow.In addition,the PersL intensity was dramatically increased by 16.8 times by codoping Tb^(3+)and Bi^(3+).Therefore,multi-mode anti-counterfeiting was achieved by multi-stimulus response.Furthermore,the dual-emission band was designed as a ratiometric PersL aptasensor for the detection of mucin 1.The detection linearity ranged from 0.1 to 100 ng mL^(−1) with a detection limit of 0.036 to 1 ng mL^(−1).This novel PLP with a dual-emission band expands the application range of PLPs.展开更多
Paper-based devices have attracted extensive attention due to their portability,low-cost,ubiquity,low environmental footprint and ease of operation.In the present study,two lanthanide complexes,namely[Eu(PBA)3(H2O)2](...Paper-based devices have attracted extensive attention due to their portability,low-cost,ubiquity,low environmental footprint and ease of operation.In the present study,two lanthanide complexes,namely[Eu(PBA)3(H2O)2](Eu-PBA)and[Tb(HPBA)2(NO3)3](Tb-HPBA)were synthesized using an amide-typeβ-diketone building block,N-(2-pyridinyl)benzoylacetamide(HPBA),which is capable of changing its energylevel to match that of Tb3+and Eu3+ions in an acid-base environment.This feature was used for the design and assembly of a simple and cost-effective paper-based lanthanide smart device(abbreviated as Paper-Eu/Tb),which was obtained by impregnating the filter paper with both the Eu-PBA and Tb-HPBA complexes;related homometallic Paper-Eu and Paper-Tb materials were also generated and characterized for comparative purposes.The obtained Paper-Eu/Tb device shows excellent luminescence properties,thus allowing its efficient use as a smart sensor for the naked-eye detection of various acid-base vapours with quick response,good reversibility and selectivity.A similar concept and the resulting paperbased device was also successfully expanded for other applications that include anti-counterfeiting and logic gate systems.Full characterization of the paper-based materials and examples of their use are described.展开更多
This study focuses on developing a deep learning model capable of recognizing vehicle brands and models,integrated with a law enforcement intelligence platform to overcome the limitations of existing license plate rec...This study focuses on developing a deep learning model capable of recognizing vehicle brands and models,integrated with a law enforcement intelligence platform to overcome the limitations of existing license plate recognition techniques—particularly in handling counterfeit,obscured,or absent plates.The research first entailed collecting,annotating,and classifying images of various vehiclemodels,leveraging image processing and feature extraction methodologies to train themodel on Microsoft Custom Vision.Experimental results indicate that,formost brands and models,the system achieves stable and relatively high performance in Precision,Recall,and Average Precision(AP).Furthermore,simulated tests involving illicit vehicles reveal that,even in cases of reassigned,concealed,or missing license plates,the model can rely on exterior body features to effectively identify vehicles,reducing dependence on plate-specific data.In practical law enforcement scenarios,these findings can accelerate investigations of stolen or forged plates and enhance overall accuracy.In conclusion,continued collection of vehicle images across broadermodel types,production years,and modification levels—along with refined annotation processes and parameter adjustment strategies—will further strengthen themethod’s applicability within law enforcement intelligence platforms,facilitating more precise and comprehensive vehicle recognition and control in real-world operations.展开更多
Over past decades,deceptive counterfeits which cannot be recognized by ordinary consumers when purchasing,such as counterfeit cosmetics,have posed serious threats on consumers’health and safety,and resulted in huge e...Over past decades,deceptive counterfeits which cannot be recognized by ordinary consumers when purchasing,such as counterfeit cosmetics,have posed serious threats on consumers’health and safety,and resulted in huge economic loss and inestimable brand damages to the genuine goods at the same time.Thus,how to effectively control and eliminate deceptive counterfeits in the market has become a critical problem to the local government.One of the principal challenges in combating the cheating action for the government is how to enhance the enforcement of relative quality inspection agencies like industrial administration office(IAO).In this paper,we formulate a two-stage counterfeit product model with a fixed checking rate from IAO and a penalty for holding counterfeits.Tominimize the total expected cost over two stages,the retailer adopts optimal ordering policies which are correlated with the checking rate and penalty.Under certain circumstances,we find that the optimal expected cost function for the retailer is first-order continuous and convex.The optimal ordering policy in stage two depends closely on the inventory level after the first sales period.When the checking rate in stage one falls into a certain range,the optimal ordering policy for the retailer at each stage is to order both kinds of products.Knowing the retailer’s optimal ordering policy at each stage,IAO can modify the checking rate accordingly to keep the ratio of deceptive counterfeits on the market under a certain level.展开更多
With the advent of the mobile Internet era,social media has developed rapidly,and its operating entities have become more diverse.Social media accounts have become external business cards of various entities such as g...With the advent of the mobile Internet era,social media has developed rapidly,and its operating entities have become more diverse.Social media accounts have become external business cards of various entities such as governments,enterprises,and individuals and are precious intangible assets.At the same time,social media accounts are also at risk of being counterfeited.展开更多
Wenhao Wang and colleagues summarized the latest advancements in structural color research in Opto-Electronic Science. Their review explored the fundamental principles and fabrication methods of structural colors for ...Wenhao Wang and colleagues summarized the latest advancements in structural color research in Opto-Electronic Science. Their review explored the fundamental principles and fabrication methods of structural colors for photonic applications, including anti-counterfeiting, displays, sensors, and printing, along with their practical limitations. Recently, structural colors have received growing interest due to their advantages, including physical and chemical robustness, ecofriendliness, tunability, and high-resolution color.展开更多
To develop near-infrared （NIR） reflectance spectroscopic methods for the quantitative analysis of cefoperazone sodium/ sulbactam sodium from different manufacturers for injection powder medicaments. Various powders ...To develop near-infrared （NIR） reflectance spectroscopic methods for the quantitative analysis of cefoperazone sodium/ sulbactam sodium from different manufacturers for injection powder medicaments. Various powders of cefoperazone sodium/ sulbactam sodium were directly analyzed by non-destructive NIR reflectance spectroscopy using the spectrometer EQUINOX55. Two quantitative methods via integrating sphere （IS） and fiberoptic probe （FOP） models were explored from 6 batches of commercial samples and 42 batches of laboratory samples at a content ranging from 30% to 70% for cefoperazone and 60% to 20% for sulbactam. The root mean square errors of cross validation （RMSECV） and the root mean square errors of prediction （RMSEP） of IS were 1.79% and 2.85%, respectively, for cefoperazone sodium, and were 1.86% and 3.08%, respectively, for sulbactam sodium; and those of FOP were 2.93% and 2.92%, respectively, for cefoperazone sodium, and were 2.23% and 3.01%, respectively, for sulbactam sodium. Based on the ICH guidelines and Ref. 12, the quantitative models were then evaluated in terms of specificity, linearity, accuracy, precision, robustness and model transferability. The non-destructive quantitative NIR methods used in this study are applicable for rapid analysis of injectable powdered drugs from different manufacturers.展开更多
Falsified antibacterial agents continue to pose serious public health problems around the world. They are notably responsible for resistance emergence in the treatment of infectious diseases that can lead to death. Th...Falsified antibacterial agents continue to pose serious public health problems around the world. They are notably responsible for resistance emergence in the treatment of infectious diseases that can lead to death. The aim of this study was to summarize the literature on the methods developed and validated to detect poor quality antibacterial agents in order to assess the impact of these available methods in the fighting against Counterfeit/substandard medicines. Thus, studies published in the time from January 2000 to July 2017, were accessible via Google Scholar and Pubmed and allowed to analyze 41 papers. The majority (30) of developed and validated methods concerned LC methods, 9 regarded UV/V is spectrophotometry and two studies simultaneously developed both methods. Antibacterial agents belonging to beta-lactams group were the most concerned by the methods developed and validated (39%), followed by quinolones (18%) and macrolides (12%). Regarding active ingredients, amoxicillin (12%) was the most concerned by the development and validation methods. In spite of several available methods to detect substandard drugs, antibacterial agents for which methods were developed and validated were the most concerned by worldwide detected non-conformities. The fight against this scourge should not be only limited by their detection, but it also requires an effective involvement of different actors notably: health authorities, international organizations, pharmaceutical industries etc.展开更多
文摘Counterfeiting is one of the most serious problems in the consumer market. One promising approach for anti-counterfeiting is to attach a low-cost Radio-frequency Identification (RFID) tag to the product authentication. In this paper, we propose an RFID system for detecting counterfeiting products. This RFID system consists of the tag authentication protocol and the database correction protocol. We use the tag authentication protocol for authenticating tags without revealing their sensitive information. This protocol also allows the customer to freely inquire the tag. To prevent the widespread of the counterfeit products, we use the tag status information along with tag identity information. Meanwhile, the database correction protocol guarantees the correctness of the tag status. Our anti-counterfeiting system is the first work considering the seller who plays an important role in the consumer product supply chain. Finally, we show that anti-counterfeiting system is quite secure against counterfeiting and the tag authentication protocol is lightweight enough to be implemented in RFID-based applications.
基金Project(51874129)supported by the National Natural Science Foundation of ChinaProjects(2018JJ3115,2019JJ60049)supported by the Science Foundation of Hunan Province,ChinaProjects(19B153,19B158)supported by the Scientific Research Fund of Hunan Provincial Education Department,China。
文摘Novel hydrophilic NaYF4:Yb^3+,Tm^3+@NaGdF4:Ce^3+,Eu^3+double-jacket microtubes(DJMTs)with upconversion/downconversion dual-mode luminescence were designed and prepared through epitaxial growth of NaGdF4:Ce^3+,Eu^3+shell onto the NaYF4:Yb^3+,Tm^3+microtube via poly(acrylic acid)(PAA)mediated hydrothermal method.It is demonstrated that PAA ligand played an important role in guiding the direct growth of NaGdF4:Ce^3+,Eu^3+shell onto the surface of NaYF4:Yb^3+,Tm^3+parent microtubes.The growth of NaGdF4:Ce^3+,Eu^3+shell experienced a crystal phase transition fromβ-NaGdF4 andβ-NaYF4 mixture toβ-NaYF4@NaGdF4 composite crystal,and morphology evolution from mixture ofβ-NaGdF4:Ce^3+,Eu^3+nanorods andβ-NaYF4:Yb^3+,Tm^3+microtubes to NaYF4:Yb^3+,Tm^3+@NaGdF4:Ce^3+,Eu^3+DJMTs.The formation mechanism of DJMTs was the dissolution−renucleation ofβ-NaGdF4:Ce^3+,Eu^3+nanorods and the growth ofβ-NaGdF4:Ce^3+,Eu^3+shell via the classical Ostwald ripening mechanism.The as-prepared DJMTs could exhibit blue upconversion and red downconversion luminescence,which was further made into environmentally benign luminescent inks for creating highly secured and fluorescent-based anti-counterfeiting patterns via inkjet printing.
文摘Pharmaceutical counterfeiting is a health scourge responsible for several cases of morbidity and mortality. Counterfeit medicines cause therapeutic failure, emergence of resistance in the treatment of infections. This study was conducted in order to identify counterfeit and authentic medicines in circulation in Lubumbashi. The study included artemether and artesunate for oral administration. A careful visual inspection of medicine, investigation of authenticity of pharmaceutical products from manufacturers and pharmaceutical regulatory authorities and determination of content were used as study parameters. 52 samples: 37 artemether and 15 of artésunate were collected. 7 samples (13%) have proven to be counterfeit. Artemether was the most counterfeit (71%) and 29% for artesunate. 6 (12%) samples were substandard according to the international pharmacopoeia in terms of content of active ingredient. Sixty-seven percent of non-compliance concerned counterfeit medicines. The proportion of non-compliance is highest among counterfeit medicines (71.43% vs 2.22%;p = 0.000004). It is obvious that strengthening the capacity of the drug regulatory authority of the DRC reduces the influx of counterfeit drug and substandard.
文摘February-15,virtual ITU is organizing a series of webinars on Combating counterfeiting and stolen information and communications technology(ICT)devices.The Episode 1:"Existing challenges and solutions on combating counterfeiting of ICT devices",will take place fully virtually on 15 February 2023.
基金supported by the National Key R&D Program of China(2023YFA1406200)the National Natural Science Foundation of China(T2521005,12174144,12474009,12174146,and 124B2059)the Special Construction Project Fund for Shan-dong Province Taishan Scholars.
文摘Multifunctional optical responsive materials have grown increasingly pivotal in addressingthe escalating demands of sensing,detection,and anti-counterfeiting applications[1,2].These materials exhibit distinct visible optical variations upon exposure to external stimuli,such as pressure,temperature,light,solvents,pH fluctuations,or mechanical force.Fluorescent sensing and anti-counterfeiting technologies leveraging these optical responses have emerged as highly promising solutions.
基金supported by the National Natural Science Foundation of China(nos.22125201,22532003,and 22405014)the China Post-Doctoral Science Foundation(no.2023 M740182)Suzhou Key Laboratory of Bio-Inspired Interfacial Science(SZ2024004).
文摘Highly ordered films of polystyrene(PS)micro-spheres have demonstrated various merits in optoelectronic devices,given their size-and thickness-dependent optical properties.So far,various solution strategies have been developed for making such highly ordered films,which have suffered from the lack of precise control on the film thickness(i.e.,layer number of micro-spheres).Here,we developed a facile fibrous liquid bridge strategy for fabricating highly ordered PS micro-sphere films,featured as the finely tunable mono-to multi-layer.Guided by a horizontally placed fiber with both ends passing through a capillary tube,respectively,the solution was transferred steadily onto the target substrate forming a homogeneous liquid film,whose dewetting process thus confines the assembly ofmicro-spheres in a well-controllablemanner.Depending on both the solution-shearing speed and the local concentration,a dynamic equilibrium between liquid transfer and evaporation was realized,which enables the formation of highly ordered micro-sphere films with finely tunable layer numbers.We demonstrated the angle-specific information encryption for anti-counterfeiting by utilizing patterned PS micro-sphere films that modulate structural colors based on layer-dependent optical responses.The result offers a new perspective for fabricating highly ordered film with tunable layers.
基金financial support from the National Natural Science Foundation of China(Grant No.21871122 and 21431002)the Fundamental Research Funds for the Central Universities(Grant No.lzujbky-2020-kb13).
文摘Lanthanide-based luminescent anticounterfeiting materials are widely used in various kinds of products.At present,the conventional lanthanide-based luminescent anticounterfeiting technique is based on photoluminescence from ultraviolet light irradiation,resulting in the decreased efficiency of anticounterfeiting applications.In this work,we realized three luminescence modes in a perovskite structure(CaTiO_(3):Pr^(3+),Er^(3+)),in which the excitation-wavelength-dependent photoluminescence(PL)emission,afterglow and upconversion luminescence(UCL)of a doped lanthanide were first presented.Upon ultraviolet excitation,the color of the PL emission can be finely tuned from red to orange,yellow and green by increasing the excitation wavelength from 365 nm to 380 nm.The doped lanthanide emits an intense green color upon illumination with a 980 nm excitation source and a long persisting red color(612 nm)when a UV lamp at 365 nm excitation is switched off.Based on the above luminescence modes of CaTiO_(3):Pr^(3+),Er^(3+),a multilevel anticounterfeiting quick response code(QR code)was developed.The QR code readily integrates the advantages of the excitation wavelength-dependent PL emissions,a strong red afterglow and sensitive excitation power-dependent UCL emissions in one overall device.The presented multilevel anticounterfeiting strategies may inspire the resolution of counterfeit issues in various fields.
基金support pro-vided in part by the Natural Science Foundation of Jiangsu Province-Outstanding Youth Foundation(BK20170104)the National Natural Science Foundation of China(21602106)+2 种基金the Six Talent Peaks Project in Jiangsu Province(XCL-037)the Strategic Pioneer Program on Space Science,Chinese Academy of Sciences(XDA15013100 and XDA15013101)the Undergraduate Innovation and Entrepreneurship Training Program(201910291053Z).
文摘To understand the fundamental mechanism of aggregation-induced phosphorescent emission(AIPE)and to improve the development of mechanochromic molecules,five new Pt(II)complexes Pt-1–Pt-5 bearing different terminal substituents on 1,3-di(2-pyridyl)benzene(N^C^N)ligands were designed and synthesized.Their photophysical properties have been investigated systematically via a series of spectroscopic methods.Upon excitation,the solid states of these Pt complexes exhibit tunable emissions from yellow to red,and complexes Pt-2 and Pt-3 with a large steric hindrance display remarkable AIPE properties in a tetrahydrofuran/H_(2)O mixture.All complexes,except Pt-5,show evident mechanochromic and vapochromic behaviors.Based on in-depth experimental studies,the reason for the mechanochromic behavior could be the change in the distance of the neighboring Pt complexes,which causes a switching of the emission state from^(3)π,π*/^(3)MLCT(metal-to-ligand charge transfer)to^(3)MLCT.The above results suggest an example of phosphorescence tuning by a switching of the triplet excited state in the solid state,and provide a mechanism of mechanochromic behavior.Furthermore,complex Pt-2 was used as an emission ink in the field of advanced anti-counterfeiting.
基金supported by the National Natural Science Foundation of China(No.51902080)the central government to guide local scientific and Technological Development(No.206Z1102G and 216Z1101G)Post-graduate’s Innovation Fund Project of Hebei University(HBU2022bs014).
文摘Here,multimodal fluorescent materials of Ca_(3)Al_(2)Ge_(3)O_(12):Mn^(2+),Cr^(3+)were synthesized by the traditional high-temperature solid-state reaction method.In this garnet Ca_(3)Al_(2)Ge_(3)O_(12) structure,Mn^(2+)and Cr^(3+)ions occupy dodecahedral sites(Ca sites)and hexahedral sites(Al sites),and can produce dynamic colortunable persistent luminescence at different concentrations,different excitations,and different temperatures;in particular,continuous luminescence with temperature(300 K–473 K)shows a color change from green to deep red.Through detailed pyrolysis studies and theoretical calculations,it is demonstrated that the double-trap structure existing in the host makes the persistent luminescence color temperaturedependent.Anti-counterfeiting and industrial inspection molds were successfully accomplished,which means Ca_(3)Al_(2)Ge_(3)O_(12):Mn^(2+),Cr^(3+)may be used in anti-counterfeiting and industrial inspection.
基金supported by the Educational Committee of Hebei Province(No.ZD2017214).
文摘Advanced anti-counterfeiting materials have great research significance in the fields of economy,safety and human health.Compared with independent color mixed anti-counterfeiting materials,ultraviolet(UV)excitation wavelength-dependent discoloration,which can realize the change of the emission peak shape and color under different excitation wavelengths,is more attractive.
基金supported by the National Natural Science Foundation of China(61705228 and 62105333)the Key Research Program of the Chinese Academy of Sciences(No.ZDRW-CN-2021-3)the Fujian Science&Technology Innovation Laboratory for Optoelectronic Information of China(2020ZZ114).
文摘Recently,persistent luminescence materials(PLMs)have attracted extensive attention in the anti-counterfeiting and information encryption fields.Unfortunately,single visible persistent luminescence(PersL)demonstrates limited information security because the changes in information coded by visible PersL can be observed by the human eyes.In this work,we develop a dual-mode PLM with ultraviolet(UV)and visible PersL.
基金supported by the National Natural Science Foundation of China(62105333)the Natural Science Foundation of Xiamen,China(3502Z20227253)+1 种基金the Key Research Program of the Chinese Academy of Sciences(ZDRW-CN-2021-3)the Fujian Science&Technology Innovation Laboratory for Optoelectronic Information of China(2020ZZ114 Z).
文摘Persistent luminescent phosphors(PLPs)have attracted much attention in anti-counterfeiting,biosensing and bioimaging due to their characteristic properties of emitting long persistent luminescence(PersL)after excitation ceases.However,most of the PLPs developed so far have only one PersL emission peak,which limits their application in advanced anti-counterfeiting and precise biosensing.Here,a series of dual-emissive Zn_(2)GeO_(4):x%Tb^(3+)/y%Bi^(3+)PLPs was prepared by codoping Tb^(3+)ions and Bi^(3+)ions to significantly improve the trap depth and trap density,resulting in a 16.8-fold increase in PersL intensity compared to the Zn_(2)GeO_(4) host.The photoluminescence(PL)color was adjusted to pale blue under 254 nm UV excitation by trap depth engineering,while the PersL color was green,and the PL color under 365 nm UV excitation was yellow.In addition,the PersL intensity was dramatically increased by 16.8 times by codoping Tb^(3+)and Bi^(3+).Therefore,multi-mode anti-counterfeiting was achieved by multi-stimulus response.Furthermore,the dual-emission band was designed as a ratiometric PersL aptasensor for the detection of mucin 1.The detection linearity ranged from 0.1 to 100 ng mL^(−1) with a detection limit of 0.036 to 1 ng mL^(−1).This novel PLP with a dual-emission band expands the application range of PLPs.
基金supported by the National Natural Science Foundation of China(Projects 21471071,21431002)the National Science Foundation for Fostering Talents in Basic Research of the National Natural Science Foundation of China(Project J1103307).
文摘Paper-based devices have attracted extensive attention due to their portability,low-cost,ubiquity,low environmental footprint and ease of operation.In the present study,two lanthanide complexes,namely[Eu(PBA)3(H2O)2](Eu-PBA)and[Tb(HPBA)2(NO3)3](Tb-HPBA)were synthesized using an amide-typeβ-diketone building block,N-(2-pyridinyl)benzoylacetamide(HPBA),which is capable of changing its energylevel to match that of Tb3+and Eu3+ions in an acid-base environment.This feature was used for the design and assembly of a simple and cost-effective paper-based lanthanide smart device(abbreviated as Paper-Eu/Tb),which was obtained by impregnating the filter paper with both the Eu-PBA and Tb-HPBA complexes;related homometallic Paper-Eu and Paper-Tb materials were also generated and characterized for comparative purposes.The obtained Paper-Eu/Tb device shows excellent luminescence properties,thus allowing its efficient use as a smart sensor for the naked-eye detection of various acid-base vapours with quick response,good reversibility and selectivity.A similar concept and the resulting paperbased device was also successfully expanded for other applications that include anti-counterfeiting and logic gate systems.Full characterization of the paper-based materials and examples of their use are described.
基金the National Science and Technology Council,Taiwan,for financially supporting this research(grant No.NSTC 114-2221-E-018-003)the Ministry of Education’s Teaching Practice Research Program,Taiwan(PSK1142780).
文摘This study focuses on developing a deep learning model capable of recognizing vehicle brands and models,integrated with a law enforcement intelligence platform to overcome the limitations of existing license plate recognition techniques—particularly in handling counterfeit,obscured,or absent plates.The research first entailed collecting,annotating,and classifying images of various vehiclemodels,leveraging image processing and feature extraction methodologies to train themodel on Microsoft Custom Vision.Experimental results indicate that,formost brands and models,the system achieves stable and relatively high performance in Precision,Recall,and Average Precision(AP).Furthermore,simulated tests involving illicit vehicles reveal that,even in cases of reassigned,concealed,or missing license plates,the model can rely on exterior body features to effectively identify vehicles,reducing dependence on plate-specific data.In practical law enforcement scenarios,these findings can accelerate investigations of stolen or forged plates and enhance overall accuracy.In conclusion,continued collection of vehicle images across broadermodel types,production years,and modification levels—along with refined annotation processes and parameter adjustment strategies—will further strengthen themethod’s applicability within law enforcement intelligence platforms,facilitating more precise and comprehensive vehicle recognition and control in real-world operations.
基金the National Natural Science Foundation of China(Nos.71390334 and 11271356).
文摘Over past decades,deceptive counterfeits which cannot be recognized by ordinary consumers when purchasing,such as counterfeit cosmetics,have posed serious threats on consumers’health and safety,and resulted in huge economic loss and inestimable brand damages to the genuine goods at the same time.Thus,how to effectively control and eliminate deceptive counterfeits in the market has become a critical problem to the local government.One of the principal challenges in combating the cheating action for the government is how to enhance the enforcement of relative quality inspection agencies like industrial administration office(IAO).In this paper,we formulate a two-stage counterfeit product model with a fixed checking rate from IAO and a penalty for holding counterfeits.Tominimize the total expected cost over two stages,the retailer adopts optimal ordering policies which are correlated with the checking rate and penalty.Under certain circumstances,we find that the optimal expected cost function for the retailer is first-order continuous and convex.The optimal ordering policy in stage two depends closely on the inventory level after the first sales period.When the checking rate in stage one falls into a certain range,the optimal ordering policy for the retailer at each stage is to order both kinds of products.Knowing the retailer’s optimal ordering policy at each stage,IAO can modify the checking rate accordingly to keep the ratio of deceptive counterfeits on the market under a certain level.
文摘With the advent of the mobile Internet era,social media has developed rapidly,and its operating entities have become more diverse.Social media accounts have become external business cards of various entities such as governments,enterprises,and individuals and are precious intangible assets.At the same time,social media accounts are also at risk of being counterfeited.
基金supported by the POSCO-POSTECH-RIST Convergence Research Center program funded by POSCOthe National Research Foundation(NRF)grants(RS-2022-NR067559,RS-2023-00302586)funded by the Ministry of Science and ICT(MSIT)of the Korean government.
文摘Wenhao Wang and colleagues summarized the latest advancements in structural color research in Opto-Electronic Science. Their review explored the fundamental principles and fabrication methods of structural colors for photonic applications, including anti-counterfeiting, displays, sensors, and printing, along with their practical limitations. Recently, structural colors have received growing interest due to their advantages, including physical and chemical robustness, ecofriendliness, tunability, and high-resolution color.
基金National Key Technologies R&D Program Foundation of China (Grant No. 2006BAK04A11)
文摘To develop near-infrared （NIR） reflectance spectroscopic methods for the quantitative analysis of cefoperazone sodium/ sulbactam sodium from different manufacturers for injection powder medicaments. Various powders of cefoperazone sodium/ sulbactam sodium were directly analyzed by non-destructive NIR reflectance spectroscopy using the spectrometer EQUINOX55. Two quantitative methods via integrating sphere （IS） and fiberoptic probe （FOP） models were explored from 6 batches of commercial samples and 42 batches of laboratory samples at a content ranging from 30% to 70% for cefoperazone and 60% to 20% for sulbactam. The root mean square errors of cross validation （RMSECV） and the root mean square errors of prediction （RMSEP） of IS were 1.79% and 2.85%, respectively, for cefoperazone sodium, and were 1.86% and 3.08%, respectively, for sulbactam sodium; and those of FOP were 2.93% and 2.92%, respectively, for cefoperazone sodium, and were 2.23% and 3.01%, respectively, for sulbactam sodium. Based on the ICH guidelines and Ref. 12, the quantitative models were then evaluated in terms of specificity, linearity, accuracy, precision, robustness and model transferability. The non-destructive quantitative NIR methods used in this study are applicable for rapid analysis of injectable powdered drugs from different manufacturers.
文摘Falsified antibacterial agents continue to pose serious public health problems around the world. They are notably responsible for resistance emergence in the treatment of infectious diseases that can lead to death. The aim of this study was to summarize the literature on the methods developed and validated to detect poor quality antibacterial agents in order to assess the impact of these available methods in the fighting against Counterfeit/substandard medicines. Thus, studies published in the time from January 2000 to July 2017, were accessible via Google Scholar and Pubmed and allowed to analyze 41 papers. The majority (30) of developed and validated methods concerned LC methods, 9 regarded UV/V is spectrophotometry and two studies simultaneously developed both methods. Antibacterial agents belonging to beta-lactams group were the most concerned by the methods developed and validated (39%), followed by quinolones (18%) and macrolides (12%). Regarding active ingredients, amoxicillin (12%) was the most concerned by the development and validation methods. In spite of several available methods to detect substandard drugs, antibacterial agents for which methods were developed and validated were the most concerned by worldwide detected non-conformities. The fight against this scourge should not be only limited by their detection, but it also requires an effective involvement of different actors notably: health authorities, international organizations, pharmaceutical industries etc.
