Sintered silver nanoparticles(AgNPs)arewidely used in high-power electronics due to their exceptional properties.However,the material reliability is significantly affected by various microscopic defects.In this work,t...Sintered silver nanoparticles(AgNPs)arewidely used in high-power electronics due to their exceptional properties.However,the material reliability is significantly affected by various microscopic defects.In this work,the three primary micro-defect types at potential stress concentrations in sintered AgNPs are identified,categorized,and quantified.Molecular dynamics(MD)simulations are employed to observe the failure evolution of different microscopic defects.The dominant mechanisms responsible for this evolution are dislocation nucleation and dislocation motion.At the same time,this paper clarifies the quantitative relationship between the tensile strain amount and the failure mechanism transitions of the three defect types by defining key strain points.The impact of defect types on the failure process is also discussed.Furthermore,traction-separation curves extracted from microscopic defect evolutions serve as a bridge to connect the macro-scale model.The validity of the crack propagation model is confirmed through tensile tests.Finally,we thoroughly analyze how micro-defect types influence macro-crack propagation and attempt to find supporting evidence from the MD model.Our findings provide a multi-perspective reference for the reliability analysis of sintered AgNPs.展开更多
Silver nanoparticles(AgNPs)synthesized using tartaric acid as a capping agent have a great impact on the reaction kinetics and contribute significantly to the stability of AgNPs.The protective layer formed by tartaric...Silver nanoparticles(AgNPs)synthesized using tartaric acid as a capping agent have a great impact on the reaction kinetics and contribute significantly to the stability of AgNPs.The protective layer formed by tartaric acid is an important factor that protects the silver surface and reduces potential cytotoxicity problems.These attributes are critical for assessing the compatibility of AgNPs with biological systems and making them suitable for drug delivery applications.The aim of this research is to conduct a comprehensive study of the effect of tartaric acid concentration,sonication time and temperature on the formation of silver nanoparticles.Using Response Surface Methodology(RSM)with Face-Centered Central Composite Design(FCCD),the optimization process identifies the most favorable synthesis conditions.UV-Vis spectrum regression analysis shows that AgNPs stabilized with tartaric acid are more stable than AgNPs without tartaric acid.This highlights the increased stability that tartaric acid provides in AgNP ssssynthesis.Particle size distribution analysis showed a multimodal distribution for AgNPs with tartaric acid and showed the smallest size peak with an average size of 20.53 nm.The second peak with increasing intensity shows a dominant average size of 108.8 nm accompanied by one standard deviation of 4.225 nm and a zeta potential of−11.08 mV.In contrast,AgNPs synthesized with polyvinylpyrrolidone(PVP)showed a unimodal particle distribution with an average particle size of 81.62 nm and a zeta potential of−2.96 mV.The more negative zeta potential of AgNP-tartaric acid indicates its increased stability.Evaluation of antibacterial activity showed that AgNPs stabilized with tartaric acid showed better performance against E.coli and B.subtilis bacteria compared with AgNPs-PVP.In summary,this study highlights the potential of tartaric acid in AgNP synthesis and suggests an avenue for the development of stable AgNPs with versatile applications.展开更多
China is striving to build an elderly-friendly society,with comfortable living facilities,convenient transportation,and accessible leisure services.THE Chinese path to modernization entails the modernization of a huge...China is striving to build an elderly-friendly society,with comfortable living facilities,convenient transportation,and accessible leisure services.THE Chinese path to modernization entails the modernization of a huge population.Part of this,as was declared at the 20th National Congress of the Communist Party of China(CPC),means China will pursue a proactive national strategy in response to population aging,and develop elderly care programs and services.To actively respond to population aging,there is more to care than just the physical health of the elderly.Their needs are multi-level and diverse.To some extent,it’s fair to say that a society’s happiness is largely dependent on whether or not the elderly are happy.The silver economy,which meets the needs of the elderly for a better life,therefore has enormous development potentials.展开更多
Developing the silver economy is not only a requirement for enhancing services for the elderly,but also an important part of achieving China's high-quality development.CHINA’s latest Central Economic Work Confere...Developing the silver economy is not only a requirement for enhancing services for the elderly,but also an important part of achieving China's high-quality development.CHINA’s latest Central Economic Work Conference held in December 2023 emphasized the need to accelerate the improvement of a childbearing supportive policy system and develop the silver economy.As a result of the rapidly aging population in China,the silver economy has risen to an unprecedented height in China’s development strategy.From concept to action,the silver economy has become a significant part of China’s active response to such national issues as population aging,boosting domestic demands,and achieving high-quality development.展开更多
The government work report delivered at the second session of the 14th National People’s Congress(NPC)in Beijing on March 5 stated that“a further push will be made to develop the silver economy.”Before this,on Janu...The government work report delivered at the second session of the 14th National People’s Congress(NPC)in Beijing on March 5 stated that“a further push will be made to develop the silver economy.”Before this,on January 15,the State Council issued Opinions on Developing the Silver Economy to Enhance the Well-being of the Elderly.The first in China dedicated to supporting the“silver economy,”the document outlines goals and measures for the development of the sector.So what can be done to seize the new opportunities emerging alongside the growing aging population to advance high-quality economic development?展开更多
Silver nanoparticles are versatile nanomaterials that have found numerous applications in various fields.The use of plant extract for the synthesis of silver is a green and sustainable approach.Clerodendron phlomoides...Silver nanoparticles are versatile nanomaterials that have found numerous applications in various fields.The use of plant extract for the synthesis of silver is a green and sustainable approach.Clerodendron phlomoides leaves extract has been found to contain various phytochemicals,such as phenols,flavonoids,tannins,and alkaloids,which possess reducing and stabilizing properties that can aid the production of silver particles.In this paper,morphological and topographical analyses were performed on silver nanoparticles.The biosynthesized silver nanoparticles showed antimicrobial potential against wound pathogens.SEM and TEM micrographs revealed that the particles were sphere and nanosized,which makes them suitable for various biomedical applications.展开更多
Silver nanoparticles(Ag NPs)are an effective antibacterial agent,but their application in food packaging is limited due to their easy agglomeration and oxidation.In this study,antibacterial microcapsules were fabricat...Silver nanoparticles(Ag NPs)are an effective antibacterial agent,but their application in food packaging is limited due to their easy agglomeration and oxidation.In this study,antibacterial microcapsules were fabricated using Ginkgo biloba essential oil(GBEO)as core material and chitosan and type B gelatin biopolymer as capsule mate-rials.These antibacterial microcapsules were then modified with green-synthesized Ag NPs,blended into the bio-polymer polylactic acid(PLA),and finally formed as films.Physicochemical properties and antibacterial activity against Escherichia coli(E.coli)and Staphylococcus aureus(S.aureus)were evaluated.Results showed that the prepared antibacterial PLA films exhibited excellent antibacterial activity against foodborne pathogens.Its TVC exceeded the limit value of 7 log CFU/g at 7 days compared with the 5 days of pure PLA films.Therefore,these films can extend the shelf life of grass carp fillets by 2–3 days under refrigeration.展开更多
Flexible electrochromic energy storage devices(FECESDs)for powering flexible electronics have attracted considerable attention.Silver nanowires(AgNWs)are one kind of the most promising flexible transparent electrodes(...Flexible electrochromic energy storage devices(FECESDs)for powering flexible electronics have attracted considerable attention.Silver nanowires(AgNWs)are one kind of the most promising flexible transparent electrodes(FTEs)materials for the emerging flexible devices.Currently,fabricating FECESD based on AgNWs FTEs is still hindered by their intrinsic poor electrochemical stability.To address this issue,a hybrid AgNWs/Co(OH)_(2)/PEDOT:PSS electrode is proposed.The PEDOT:PSS could not only improve the resistance against electrochemical corrosion of AgNWs,but also work as functional layer to realize the color-changing and energy storage properties.Moreover,the Co(OH)_(2)interlayer further improved the color-changing and energy storage performance.Based on the improvement,we assembled the symmetrical FECESDs.Under the same condition,the areal capacitance(0.8 mF cm^(−2))and coloration efficiency(269.80 cm^(2)C−1)of AgNWs/Co(OH)_(2)/PEDOT:PSS FECESDs were obviously higher than AgNWs/PEDOT:PSS FECESDs.Furthermore,the obtained FECESDs exhibited excellent stability against the mechanical deformation.The areal capacitance remained stable during 1000 times cyclic bending with a 25 mm curvature radius.These results demonstrated the broad application potential of the AgNWs/Co(OH)_(2)/PEDOT:PSS FECESD for the emerging portable and multifunctional electronics.展开更多
The poly(epoxy-N-methylaniline)conductive organic carrier was used as the bonding phase of the low-temperature conductive silver paste.Then,this was mixed with different proportions of silver powder to prepare the low...The poly(epoxy-N-methylaniline)conductive organic carrier was used as the bonding phase of the low-temperature conductive silver paste.Then,this was mixed with different proportions of silver powder to prepare the low-temperature conductive silver paste.Afterwards,the effect of the conductive organic carrier on the properties of the low-temperature conductive silver paste was determined by IR,DMA and SEM.The results revealed that the prepared conductive paste has good conductivity,film-forming performance,printing performance,low-temperature curing performance,and anti-aging performance.When the mass percentage of the bonding phase/conductive phase was 40/60,the lowest volume resistivity of the conductive silver paste was 4.9×10^(−6)Ω⋅cm,and the conductivity was the best.展开更多
目的:对1例产前B超提示骨骼系统发育异常,疑似宫内生长受限的胎儿进行基因检测及生物信息学分析以明确其致病原因。方法:采集胎儿羊水及父母外周血,提取基因组DNA,利用高通量测序平台进行家系全外显子组测序(whole exome sequencing,WES...目的:对1例产前B超提示骨骼系统发育异常,疑似宫内生长受限的胎儿进行基因检测及生物信息学分析以明确其致病原因。方法:采集胎儿羊水及父母外周血,提取基因组DNA,利用高通量测序平台进行家系全外显子组测序(whole exome sequencing,WES)及拷贝数变异测序(copy number variation sequencing,CNV-seq)技术检测,可疑结果经Sanger测序进行验证。结果:胎儿高迁移率族蛋白A2(high mobility group protein AT-Hook-2,HMGA2)基因存在c.223C>T(p.R75W)新发变异,导致氨基酸改变为p.R75W(p.Arg75Trp),为错义突变。根据美国医学遗传学与基因组学学会(American College of Medical Genetics and Genomics,ACMG)指南评级,该变异判定为可能致病性(likely pathogenic):PS2+PM2_Supporting+PP3+PS4_Supporting。根据其临床表型,该胎儿被确诊为常染色体显性遗传的Silver-Russell综合征5型(Silver-Russell syndrome 5,SRS5)。Sanger测序确证了其变异的真实性。结论:HMGA2基因的c.223C>T(p.R75W)杂合致病性变异可能是SRS5的遗传学致病原因,扩充了该基因的变异谱,同时为该胎儿的产前遗传咨询和后续的干预措施提供了理论依据。展开更多
The introduction of bifunctional groups into low-cost adsorbents for selective adsorption of Ag(I) through synergistic effect will have a profound impact on the recovery of precious metals. Organo silica nanosheets(or...The introduction of bifunctional groups into low-cost adsorbents for selective adsorption of Ag(I) through synergistic effect will have a profound impact on the recovery of precious metals. Organo silica nanosheets(organo-Si NSs) functionalized by series of azole derivatives(2-mercaptoimidazole(MI), 2-mercaptobenzimidazole(MBT) and 1H-1,2,4-triazole-3-thiol(MTT)), are fabricated and employed for selective removal of Ag(I). The structures of the organo-Si NSs are investigated using several characterization methods. The results of batch adsorption experiments display that the maximum adsorption amounts are 70.3, 103.2 and 139.5 mg·g^(-1) on MI-Si NSs, MBI-Si NSs and MTT-Si NSs for Ag(I) ions, and reach rapid equilibrium within 10–30 min. The adsorption processes are chemisorption and fit pseudo-second-order kinetic model and Langmuir adsorption isotherm model. Notably, MTT-Si NSs is greatly selective for Ag(I) in multicomponent system, and the distribution coefficient value of Ag(I) ions reaches 2331.26 ml·g^(-1). The reusability of organo-Si NSs is verified by four cycles of regeneration tests with 0.1 mol·L^(-1) HNO_(3) as the eluent. A combination of experimental, structural along with theoretical analysis is conducted to proclaim the structure-adsorptivity relationship:(i) The adsorption mechanisms are attributed to complexation.(ii) The amino group and sulfhydryl group of MTT-Si NSs as well as MBISi NSs may have synergistic impacts on Ag(I) capture.(iii) The differences in adsorption behavior and selectivity of the three organo-Si NSs are mainly related to the form of function groups, charge density and steric hindrance of adsorbent. This work not only sheds light on the promise of functionalized organo-Si NSs for the rapid and selective removal/enrichment of Ag(I) ions in complex water systems,but also provides new insights for designing cost-effective Si NSs-based adsorbents.展开更多
Objective:To assess the molluscicidal effect of the eco-friendly green synthesized neem silver nanoparticles(neem-Ag NPs)against Biomphalaria alexandrina,the snail intermediate host for Schistosoma mansoni,and their c...Objective:To assess the molluscicidal effect of the eco-friendly green synthesized neem silver nanoparticles(neem-Ag NPs)against Biomphalaria alexandrina,the snail intermediate host for Schistosoma mansoni,and their cercaricidal potential.Methods:Methanol extracts from neem fruits were used for green synthesis of neem-Ag NPs.The neem-Ag NPs were characterized using UV-visible absorption spectra,dynamic laser light scattering technique,and transmission electron microscopy.The potential molluscicidal effect against adult and juvenile Biomphalaria alexandrina and the effect of the sub-lethal concentration on hatching of snail eggs and Schistosoma mansoni cercariae were evaluated.Results:The surface plasmon resonance of neem-Ag NPs showed a sharp absorption peak atλ_(max)=518 nm together with multiple peaks.The hydrodynamic diameter was(77.15±34.53)nm,the polydispersity index(0.338±0.000)and the zeta-potential-14.07 mV.Moreover,transmission electron microscopy showed that the average size of the nanoparticles was(27±2)nm.Agglomeration was evident and a light-colored capping layer could be seen coating the nanoparticles.Juvenile snails(LC_(50):0.83 ppm)were more susceptible to neem-Ag NPs than adults(LC_(50):1.07 ppm).In addition,neem-Ag NPs and neem at LC_(50)concentrations inhibited the egg-hatching of snails and showed cercaricidal activity in a time-dependent manner.Conclusions:Neem-Ag NPs have lethal activities against Biomphalaria alexandrina snails and their eggs,as well as Schistosoma mansoni cercariae.Hence,neem-Ag NPs could be a potential agent to control schistosomiasis.展开更多
Silver nanoclusters(AgNCs)are a new type of nanomaterials with similar properties to molecules and unique applications.The applications of AgNCs can be significantly expanded by combining them with different matrix ma...Silver nanoclusters(AgNCs)are a new type of nanomaterials with similar properties to molecules and unique applications.The applications of AgNCs can be significantly expanded by combining them with different matrix materials to obtain AgNC composites.Using irradiation techniques,we developed a simple two-step method for preparing silver nanocluster composites.First,polyacrylic acid(PAA)chains were grafted onto the surface of a PE film as templates(PE-g-PAA).Subsequently,silver ions were reduced in situ on the surface of the template material to obtain the AgNC composites(AgNCs@PE-g-PAA).The degree of AgNC loading on the composite film was easily controlled by adjusting the reaction conditions.The loaded AgNCs were anchored to the carboxyl groups of the PAA and wrapped in the graft chain.The particle size of the AgNCs was only 4.38±0.85 nm,with a very uniform particle size distribution.The AgNCs@PE-g-PAA exhibited fluorescence characteristics derived from the AgNCs.The fluorescence of the AgNCs@PE-g-PAA was easily quenched by Cr^(3+)ions.The composite can be used as a fluorescence test paper to realize visual detection of Cr^(3+).展开更多
A silver microelectrode with a diameter of 30μm in an aqueous K_(2)SO_(4) electrolyte was irradiated with 55 fs and 213 fs laser pulses.This caused the emission of electrons which transiently charged the electrochemi...A silver microelectrode with a diameter of 30μm in an aqueous K_(2)SO_(4) electrolyte was irradiated with 55 fs and 213 fs laser pulses.This caused the emission of electrons which transiently charged the electrochemical double layer.The two applied pulse durations were significantly shorter than the electron-phonon relaxation time.The laser pulse durations had negligible impact on the emitted charge,which is incompatible with multiphoton emission.On the other hand,the ob-served dependence of emitted charge on laser fluence and electrode potential supports the thermionic emission mechanism.展开更多
This article describes a method for synthesizing butyrolactone dimers using various inorganic silver salt catalysts.The method was successfully applied to alkyl 2-(2-bromopropyl)malonate 1,providing the dimeric butyro...This article describes a method for synthesizing butyrolactone dimers using various inorganic silver salt catalysts.The method was successfully applied to alkyl 2-(2-bromopropyl)malonate 1,providing the dimeric butyrolactone 2 when catalyzed by different silver salt catalysts.This synthesis method not only simplifies the original synthetic route,but also cleverly combines with natural product analogs,providing a strategy for the development of natural product polymer analogs in the future.展开更多
The electronic product has gravitated towards component miniaturization and integration, employment of lead-free materials, and low-temperature soldering processes. Noble-metal aerogels have drawn increasing attention...The electronic product has gravitated towards component miniaturization and integration, employment of lead-free materials, and low-temperature soldering processes. Noble-metal aerogels have drawn increasing attention for high conduction and low density. However,the noble metal aerogels with outstanding solderability were rarely studied. This work has successfully synthesized an aerogel derived from silver nanowires(AgNWs) using a liquid phase reduction method. It is found that the noble metal aerogels can be made into diverse aerogel preformed soldering sheets. The influence of bonding temperature(150-300 ℃), time(2-20 min), and pressure(5-20 MPa) on the joint strength of the AgNWs aerogel affixed to electroless nickel/silver copper plates were investigated. Additionally, the AgNWs aerogel displays almost the same shear strength for substrates of various sizes. In a word, this study presents a flux-free, high-strength, and adaptable soldering structural material.展开更多
BACKGROUND The demand for the development of cancer nanomedicine has increased due to its great therapeutic value that can overcome the limitations of conventional cancer therapy.However,the presence of various bioact...BACKGROUND The demand for the development of cancer nanomedicine has increased due to its great therapeutic value that can overcome the limitations of conventional cancer therapy.However,the presence of various bioactive compounds in crude plant extracts used for the synthesis of silver nanoparticles(AgNPs)makes its precise mechanisms of action unclear.AIM To assessed the mRNA transcriptome profiling of human HepG2 cells exposed to Catharanthus roseus G.Don(C.roseus)-AgNPs.METHODS The proliferative activity of hepatocellular carcinoma(HepG2)and normal human liver(THLE3)cells treated with C.roseusAgNPs were measured using MTT assay.The RNA samples were extracted and sequenced using BGIseq500 platform.This is followed by data filtering,mapping,gene expression analysis,differentially expression genes analysis,Gene Ontology analysis,and pathway analysis.RESULTS The mean IC 50 values of C.roseusAgNPs on HepG2 was 4.38±1.59μg/mL while on THLE3 cells was 800±1.55μg/mL.Transcriptome profiling revealed an alteration of 296 genes.C.roseusAgNPs induced the expression of stress-associated genes such as MT,HSP and HMOX-1.Cellular signalling pathways were potentially activated through MAPK,TNF and TGF pathways that are responsible for apoptosis and cell cycle arrest.The alteration of ARF6,EHD2,FGFR3,RhoA,EEA1,VPS28,VPS25,and TSG101 indicated the uptake of C.roseus-AgNPs via both clathrin-dependent and clathrinindependent endocytosis.CONCLUSION This study provides new insights into gene expression study of biosynthesised AgNPs on cancer cells.The cytotoxicity effect is mediated by the aberrant gene alteration,and more interestingly the unique selective antiproliferative properties indicate the C.roseusAgNPs as an ideal anticancer candidate.展开更多
A plasmonic effect of silver nanoparticles (AgNPs) in dye-sensitized solar cells (DSSCs) is studied. In this investigation, the efficiency of dye-sensitized solar cells has been remarkably increased by infusion of syn...A plasmonic effect of silver nanoparticles (AgNPs) in dye-sensitized solar cells (DSSCs) is studied. In this investigation, the efficiency of dye-sensitized solar cells has been remarkably increased by infusion of synthesized silver nanoparticles into the TiO<sub>2</sub> photoanode. Rhodaminederivative RdS1 was synthesized by microwave-assisted condensation of hydrazide and 3-for-mylchromone. The synthesized silver nanoparticles were characterized with UV/Vis absorption spectroscopy and transmission electron microscopy. The interfacial charge transport phenomena of the dye-sensitized solar cell (DSSCs) are determined by electrochemical impedance spectroscopy and the corresponding efficiencies are calculated using current-voltage (I-V) curve. The solar cell photoanode with silver nanoparticles infused with RdS1 in titanium dioxide had the highest solar-to-electric power efficiency at 0.17%.展开更多
基金supported by the China Scholarship Council (CSC) (No.202206020149)the Academic Excellence Foundation of BUAA for PhD Students,the Funding Project of Science and Technology on Reliability and Environmental Engineering Laboratory (No.6142004210106).
文摘Sintered silver nanoparticles(AgNPs)arewidely used in high-power electronics due to their exceptional properties.However,the material reliability is significantly affected by various microscopic defects.In this work,the three primary micro-defect types at potential stress concentrations in sintered AgNPs are identified,categorized,and quantified.Molecular dynamics(MD)simulations are employed to observe the failure evolution of different microscopic defects.The dominant mechanisms responsible for this evolution are dislocation nucleation and dislocation motion.At the same time,this paper clarifies the quantitative relationship between the tensile strain amount and the failure mechanism transitions of the three defect types by defining key strain points.The impact of defect types on the failure process is also discussed.Furthermore,traction-separation curves extracted from microscopic defect evolutions serve as a bridge to connect the macro-scale model.The validity of the crack propagation model is confirmed through tensile tests.Finally,we thoroughly analyze how micro-defect types influence macro-crack propagation and attempt to find supporting evidence from the MD model.Our findings provide a multi-perspective reference for the reliability analysis of sintered AgNPs.
基金funded by the Directorate of Research and Community Service (DRPM,Direktorat Riset dan Pengabdian Kepada Masyarakat)ITS through the ITS Research Local Grant (No:1665/PKS/ITS/2023).
文摘Silver nanoparticles(AgNPs)synthesized using tartaric acid as a capping agent have a great impact on the reaction kinetics and contribute significantly to the stability of AgNPs.The protective layer formed by tartaric acid is an important factor that protects the silver surface and reduces potential cytotoxicity problems.These attributes are critical for assessing the compatibility of AgNPs with biological systems and making them suitable for drug delivery applications.The aim of this research is to conduct a comprehensive study of the effect of tartaric acid concentration,sonication time and temperature on the formation of silver nanoparticles.Using Response Surface Methodology(RSM)with Face-Centered Central Composite Design(FCCD),the optimization process identifies the most favorable synthesis conditions.UV-Vis spectrum regression analysis shows that AgNPs stabilized with tartaric acid are more stable than AgNPs without tartaric acid.This highlights the increased stability that tartaric acid provides in AgNP ssssynthesis.Particle size distribution analysis showed a multimodal distribution for AgNPs with tartaric acid and showed the smallest size peak with an average size of 20.53 nm.The second peak with increasing intensity shows a dominant average size of 108.8 nm accompanied by one standard deviation of 4.225 nm and a zeta potential of−11.08 mV.In contrast,AgNPs synthesized with polyvinylpyrrolidone(PVP)showed a unimodal particle distribution with an average particle size of 81.62 nm and a zeta potential of−2.96 mV.The more negative zeta potential of AgNP-tartaric acid indicates its increased stability.Evaluation of antibacterial activity showed that AgNPs stabilized with tartaric acid showed better performance against E.coli and B.subtilis bacteria compared with AgNPs-PVP.In summary,this study highlights the potential of tartaric acid in AgNP synthesis and suggests an avenue for the development of stable AgNPs with versatile applications.
文摘China is striving to build an elderly-friendly society,with comfortable living facilities,convenient transportation,and accessible leisure services.THE Chinese path to modernization entails the modernization of a huge population.Part of this,as was declared at the 20th National Congress of the Communist Party of China(CPC),means China will pursue a proactive national strategy in response to population aging,and develop elderly care programs and services.To actively respond to population aging,there is more to care than just the physical health of the elderly.Their needs are multi-level and diverse.To some extent,it’s fair to say that a society’s happiness is largely dependent on whether or not the elderly are happy.The silver economy,which meets the needs of the elderly for a better life,therefore has enormous development potentials.
文摘Developing the silver economy is not only a requirement for enhancing services for the elderly,but also an important part of achieving China's high-quality development.CHINA’s latest Central Economic Work Conference held in December 2023 emphasized the need to accelerate the improvement of a childbearing supportive policy system and develop the silver economy.As a result of the rapidly aging population in China,the silver economy has risen to an unprecedented height in China’s development strategy.From concept to action,the silver economy has become a significant part of China’s active response to such national issues as population aging,boosting domestic demands,and achieving high-quality development.
文摘The government work report delivered at the second session of the 14th National People’s Congress(NPC)in Beijing on March 5 stated that“a further push will be made to develop the silver economy.”Before this,on January 15,the State Council issued Opinions on Developing the Silver Economy to Enhance the Well-being of the Elderly.The first in China dedicated to supporting the“silver economy,”the document outlines goals and measures for the development of the sector.So what can be done to seize the new opportunities emerging alongside the growing aging population to advance high-quality economic development?
文摘Silver nanoparticles are versatile nanomaterials that have found numerous applications in various fields.The use of plant extract for the synthesis of silver is a green and sustainable approach.Clerodendron phlomoides leaves extract has been found to contain various phytochemicals,such as phenols,flavonoids,tannins,and alkaloids,which possess reducing and stabilizing properties that can aid the production of silver particles.In this paper,morphological and topographical analyses were performed on silver nanoparticles.The biosynthesized silver nanoparticles showed antimicrobial potential against wound pathogens.SEM and TEM micrographs revealed that the particles were sphere and nanosized,which makes them suitable for various biomedical applications.
基金supported by the National Key R&D Program of China(Grant No.2020YFD0900905).
文摘Silver nanoparticles(Ag NPs)are an effective antibacterial agent,but their application in food packaging is limited due to their easy agglomeration and oxidation.In this study,antibacterial microcapsules were fabricated using Ginkgo biloba essential oil(GBEO)as core material and chitosan and type B gelatin biopolymer as capsule mate-rials.These antibacterial microcapsules were then modified with green-synthesized Ag NPs,blended into the bio-polymer polylactic acid(PLA),and finally formed as films.Physicochemical properties and antibacterial activity against Escherichia coli(E.coli)and Staphylococcus aureus(S.aureus)were evaluated.Results showed that the prepared antibacterial PLA films exhibited excellent antibacterial activity against foodborne pathogens.Its TVC exceeded the limit value of 7 log CFU/g at 7 days compared with the 5 days of pure PLA films.Therefore,these films can extend the shelf life of grass carp fillets by 2–3 days under refrigeration.
基金supports from the National Natural Science Foundation of China (Grant No. 52175300)Fundamental Research Funds for the Central Universities (2022FRFK060008)+2 种基金Heilongjiang Touyan Innovation Team Program (HITTY-20190013)Shenzhen Fundamental Research Programs (JCYJ20200925160843002)Start-up fund of SUSTech (Y01256114)
文摘Flexible electrochromic energy storage devices(FECESDs)for powering flexible electronics have attracted considerable attention.Silver nanowires(AgNWs)are one kind of the most promising flexible transparent electrodes(FTEs)materials for the emerging flexible devices.Currently,fabricating FECESD based on AgNWs FTEs is still hindered by their intrinsic poor electrochemical stability.To address this issue,a hybrid AgNWs/Co(OH)_(2)/PEDOT:PSS electrode is proposed.The PEDOT:PSS could not only improve the resistance against electrochemical corrosion of AgNWs,but also work as functional layer to realize the color-changing and energy storage properties.Moreover,the Co(OH)_(2)interlayer further improved the color-changing and energy storage performance.Based on the improvement,we assembled the symmetrical FECESDs.Under the same condition,the areal capacitance(0.8 mF cm^(−2))and coloration efficiency(269.80 cm^(2)C−1)of AgNWs/Co(OH)_(2)/PEDOT:PSS FECESDs were obviously higher than AgNWs/PEDOT:PSS FECESDs.Furthermore,the obtained FECESDs exhibited excellent stability against the mechanical deformation.The areal capacitance remained stable during 1000 times cyclic bending with a 25 mm curvature radius.These results demonstrated the broad application potential of the AgNWs/Co(OH)_(2)/PEDOT:PSS FECESD for the emerging portable and multifunctional electronics.
基金fund for this work was provided by the“Research on Key Technologies of Photosensitive Conductive Silver Paste Based on Domestic Circuit Protection Micro Chip Components”(Project No.BE2020008 and Supporting Author:Chen P).
文摘The poly(epoxy-N-methylaniline)conductive organic carrier was used as the bonding phase of the low-temperature conductive silver paste.Then,this was mixed with different proportions of silver powder to prepare the low-temperature conductive silver paste.Afterwards,the effect of the conductive organic carrier on the properties of the low-temperature conductive silver paste was determined by IR,DMA and SEM.The results revealed that the prepared conductive paste has good conductivity,film-forming performance,printing performance,low-temperature curing performance,and anti-aging performance.When the mass percentage of the bonding phase/conductive phase was 40/60,the lowest volume resistivity of the conductive silver paste was 4.9×10^(−6)Ω⋅cm,and the conductivity was the best.
文摘目的:对1例产前B超提示骨骼系统发育异常,疑似宫内生长受限的胎儿进行基因检测及生物信息学分析以明确其致病原因。方法:采集胎儿羊水及父母外周血,提取基因组DNA,利用高通量测序平台进行家系全外显子组测序(whole exome sequencing,WES)及拷贝数变异测序(copy number variation sequencing,CNV-seq)技术检测,可疑结果经Sanger测序进行验证。结果:胎儿高迁移率族蛋白A2(high mobility group protein AT-Hook-2,HMGA2)基因存在c.223C>T(p.R75W)新发变异,导致氨基酸改变为p.R75W(p.Arg75Trp),为错义突变。根据美国医学遗传学与基因组学学会(American College of Medical Genetics and Genomics,ACMG)指南评级,该变异判定为可能致病性(likely pathogenic):PS2+PM2_Supporting+PP3+PS4_Supporting。根据其临床表型,该胎儿被确诊为常染色体显性遗传的Silver-Russell综合征5型(Silver-Russell syndrome 5,SRS5)。Sanger测序确证了其变异的真实性。结论:HMGA2基因的c.223C>T(p.R75W)杂合致病性变异可能是SRS5的遗传学致病原因,扩充了该基因的变异谱,同时为该胎儿的产前遗传咨询和后续的干预措施提供了理论依据。
基金the National Natural Science Foundation of China (21776306)。
文摘The introduction of bifunctional groups into low-cost adsorbents for selective adsorption of Ag(I) through synergistic effect will have a profound impact on the recovery of precious metals. Organo silica nanosheets(organo-Si NSs) functionalized by series of azole derivatives(2-mercaptoimidazole(MI), 2-mercaptobenzimidazole(MBT) and 1H-1,2,4-triazole-3-thiol(MTT)), are fabricated and employed for selective removal of Ag(I). The structures of the organo-Si NSs are investigated using several characterization methods. The results of batch adsorption experiments display that the maximum adsorption amounts are 70.3, 103.2 and 139.5 mg·g^(-1) on MI-Si NSs, MBI-Si NSs and MTT-Si NSs for Ag(I) ions, and reach rapid equilibrium within 10–30 min. The adsorption processes are chemisorption and fit pseudo-second-order kinetic model and Langmuir adsorption isotherm model. Notably, MTT-Si NSs is greatly selective for Ag(I) in multicomponent system, and the distribution coefficient value of Ag(I) ions reaches 2331.26 ml·g^(-1). The reusability of organo-Si NSs is verified by four cycles of regeneration tests with 0.1 mol·L^(-1) HNO_(3) as the eluent. A combination of experimental, structural along with theoretical analysis is conducted to proclaim the structure-adsorptivity relationship:(i) The adsorption mechanisms are attributed to complexation.(ii) The amino group and sulfhydryl group of MTT-Si NSs as well as MBISi NSs may have synergistic impacts on Ag(I) capture.(iii) The differences in adsorption behavior and selectivity of the three organo-Si NSs are mainly related to the form of function groups, charge density and steric hindrance of adsorbent. This work not only sheds light on the promise of functionalized organo-Si NSs for the rapid and selective removal/enrichment of Ag(I) ions in complex water systems,but also provides new insights for designing cost-effective Si NSs-based adsorbents.
文摘Objective:To assess the molluscicidal effect of the eco-friendly green synthesized neem silver nanoparticles(neem-Ag NPs)against Biomphalaria alexandrina,the snail intermediate host for Schistosoma mansoni,and their cercaricidal potential.Methods:Methanol extracts from neem fruits were used for green synthesis of neem-Ag NPs.The neem-Ag NPs were characterized using UV-visible absorption spectra,dynamic laser light scattering technique,and transmission electron microscopy.The potential molluscicidal effect against adult and juvenile Biomphalaria alexandrina and the effect of the sub-lethal concentration on hatching of snail eggs and Schistosoma mansoni cercariae were evaluated.Results:The surface plasmon resonance of neem-Ag NPs showed a sharp absorption peak atλ_(max)=518 nm together with multiple peaks.The hydrodynamic diameter was(77.15±34.53)nm,the polydispersity index(0.338±0.000)and the zeta-potential-14.07 mV.Moreover,transmission electron microscopy showed that the average size of the nanoparticles was(27±2)nm.Agglomeration was evident and a light-colored capping layer could be seen coating the nanoparticles.Juvenile snails(LC_(50):0.83 ppm)were more susceptible to neem-Ag NPs than adults(LC_(50):1.07 ppm).In addition,neem-Ag NPs and neem at LC_(50)concentrations inhibited the egg-hatching of snails and showed cercaricidal activity in a time-dependent manner.Conclusions:Neem-Ag NPs have lethal activities against Biomphalaria alexandrina snails and their eggs,as well as Schistosoma mansoni cercariae.Hence,neem-Ag NPs could be a potential agent to control schistosomiasis.
基金supported by the Gansu Natural Science Foundation (Nos.20JR10RA778 and 20JR10RA777)。
文摘Silver nanoclusters(AgNCs)are a new type of nanomaterials with similar properties to molecules and unique applications.The applications of AgNCs can be significantly expanded by combining them with different matrix materials to obtain AgNC composites.Using irradiation techniques,we developed a simple two-step method for preparing silver nanocluster composites.First,polyacrylic acid(PAA)chains were grafted onto the surface of a PE film as templates(PE-g-PAA).Subsequently,silver ions were reduced in situ on the surface of the template material to obtain the AgNC composites(AgNCs@PE-g-PAA).The degree of AgNC loading on the composite film was easily controlled by adjusting the reaction conditions.The loaded AgNCs were anchored to the carboxyl groups of the PAA and wrapped in the graft chain.The particle size of the AgNCs was only 4.38±0.85 nm,with a very uniform particle size distribution.The AgNCs@PE-g-PAA exhibited fluorescence characteristics derived from the AgNCs.The fluorescence of the AgNCs@PE-g-PAA was easily quenched by Cr^(3+)ions.The composite can be used as a fluorescence test paper to realize visual detection of Cr^(3+).
文摘A silver microelectrode with a diameter of 30μm in an aqueous K_(2)SO_(4) electrolyte was irradiated with 55 fs and 213 fs laser pulses.This caused the emission of electrons which transiently charged the electrochemical double layer.The two applied pulse durations were significantly shorter than the electron-phonon relaxation time.The laser pulse durations had negligible impact on the emitted charge,which is incompatible with multiphoton emission.On the other hand,the ob-served dependence of emitted charge on laser fluence and electrode potential supports the thermionic emission mechanism.
基金Project supported by the Natural Science Foundation of Shandong Province(No.ZR2021MB102).
文摘This article describes a method for synthesizing butyrolactone dimers using various inorganic silver salt catalysts.The method was successfully applied to alkyl 2-(2-bromopropyl)malonate 1,providing the dimeric butyrolactone 2 when catalyzed by different silver salt catalysts.This synthesis method not only simplifies the original synthetic route,but also cleverly combines with natural product analogs,providing a strategy for the development of natural product polymer analogs in the future.
基金the National Natural Science Foundation of China(Grant No.52075125,No.52105331)the Shenzhen Science and Technology Innovation Committee(Grant No.JCYJ20210324124203009,No.JSGG20201102154600003,No.GXWD20220818163456002)+1 种基金Special Fund for Science and Technology Innovation Strategy of Guangdong Province(Grant No.pdjh2022b0570)Sustainedly Supported Fundation by National Key Laboratory of Science and Technology on Space Microwave under Grant HTKJ2022KL504011,and NIO University Programme(NIO UP).
文摘The electronic product has gravitated towards component miniaturization and integration, employment of lead-free materials, and low-temperature soldering processes. Noble-metal aerogels have drawn increasing attention for high conduction and low density. However,the noble metal aerogels with outstanding solderability were rarely studied. This work has successfully synthesized an aerogel derived from silver nanowires(AgNWs) using a liquid phase reduction method. It is found that the noble metal aerogels can be made into diverse aerogel preformed soldering sheets. The influence of bonding temperature(150-300 ℃), time(2-20 min), and pressure(5-20 MPa) on the joint strength of the AgNWs aerogel affixed to electroless nickel/silver copper plates were investigated. Additionally, the AgNWs aerogel displays almost the same shear strength for substrates of various sizes. In a word, this study presents a flux-free, high-strength, and adaptable soldering structural material.
基金Fundamental Research Grant Scheme from the Malaysian Ministry of Higher Education,No.FRGS/1/2015/SG03/USM/03/1。
文摘BACKGROUND The demand for the development of cancer nanomedicine has increased due to its great therapeutic value that can overcome the limitations of conventional cancer therapy.However,the presence of various bioactive compounds in crude plant extracts used for the synthesis of silver nanoparticles(AgNPs)makes its precise mechanisms of action unclear.AIM To assessed the mRNA transcriptome profiling of human HepG2 cells exposed to Catharanthus roseus G.Don(C.roseus)-AgNPs.METHODS The proliferative activity of hepatocellular carcinoma(HepG2)and normal human liver(THLE3)cells treated with C.roseusAgNPs were measured using MTT assay.The RNA samples were extracted and sequenced using BGIseq500 platform.This is followed by data filtering,mapping,gene expression analysis,differentially expression genes analysis,Gene Ontology analysis,and pathway analysis.RESULTS The mean IC 50 values of C.roseusAgNPs on HepG2 was 4.38±1.59μg/mL while on THLE3 cells was 800±1.55μg/mL.Transcriptome profiling revealed an alteration of 296 genes.C.roseusAgNPs induced the expression of stress-associated genes such as MT,HSP and HMOX-1.Cellular signalling pathways were potentially activated through MAPK,TNF and TGF pathways that are responsible for apoptosis and cell cycle arrest.The alteration of ARF6,EHD2,FGFR3,RhoA,EEA1,VPS28,VPS25,and TSG101 indicated the uptake of C.roseus-AgNPs via both clathrin-dependent and clathrinindependent endocytosis.CONCLUSION This study provides new insights into gene expression study of biosynthesised AgNPs on cancer cells.The cytotoxicity effect is mediated by the aberrant gene alteration,and more interestingly the unique selective antiproliferative properties indicate the C.roseusAgNPs as an ideal anticancer candidate.
文摘A plasmonic effect of silver nanoparticles (AgNPs) in dye-sensitized solar cells (DSSCs) is studied. In this investigation, the efficiency of dye-sensitized solar cells has been remarkably increased by infusion of synthesized silver nanoparticles into the TiO<sub>2</sub> photoanode. Rhodaminederivative RdS1 was synthesized by microwave-assisted condensation of hydrazide and 3-for-mylchromone. The synthesized silver nanoparticles were characterized with UV/Vis absorption spectroscopy and transmission electron microscopy. The interfacial charge transport phenomena of the dye-sensitized solar cell (DSSCs) are determined by electrochemical impedance spectroscopy and the corresponding efficiencies are calculated using current-voltage (I-V) curve. The solar cell photoanode with silver nanoparticles infused with RdS1 in titanium dioxide had the highest solar-to-electric power efficiency at 0.17%.
