The flotation separation of argentite from sphalerite using ammonium dibutyl dithiophosphate(ADD)was studied.Molecular simulation(MS)calculation shows that ADD is chemisorbed on argentite and sphalerite surface in the...The flotation separation of argentite from sphalerite using ammonium dibutyl dithiophosphate(ADD)was studied.Molecular simulation(MS)calculation shows that ADD is chemisorbed on argentite and sphalerite surface in the form of S—P bond.The ADD adsorption on argentite and sphalerite surface in Ag^(+)system was revealed by ICP,Zeta potential and XPS analyses.It is shown that the dissolved Ag^(+)from argentite surface can be absorbed on sphalerite surface in the form of silver hydroxide,and AgOH hydrophilic colloid prevents the adsorption of ADD on sphalerite surface.The ADD adsorption on argentite and sphalerite surface in the pulp containing silver and zinc ions was revealed by adsorption capacity and surface wettability analyses.It is shown that the combined Zn(OH)_(2) and AgOH hydrophilic colloid leads to greater ADD adsorption capacity on argentite surface and stronger surface hydrophobicity than sphalerite.Flotation tests demonstrate that ADD enables efficient separation of argentite from sphalerite in the pulp containing silver and zinc ions.展开更多
“Are you dead?”It's not a morbid joke-it's the literal translation of the name of Chinese app Sileme,which went viral around the country in early January.However,amid public controversy over its unsettling c...“Are you dead?”It's not a morbid joke-it's the literal translation of the name of Chinese app Sileme,which went viral around the country in early January.However,amid public controversy over its unsettling connotations,the development team rebranded the app as Demumu on January 14,be-fore it was removed from the app stores of Apple and Android on January 15.展开更多
Electronic 3D printing possesses a remarkable molding ability and convenience in integrated circuits,flexible wearables,and individual automobile requirements.However,traditional 3D printing technology still struggles...Electronic 3D printing possesses a remarkable molding ability and convenience in integrated circuits,flexible wearables,and individual automobile requirements.However,traditional 3D printing technology still struggles to meet the demands of high precision and high efficiency in the process of fabricating a curved surface circuit,particularly achieving precise silver circuit molding on irregular substrates.Here,a high-precision and muti-scaled conformal manufacturing method for silver circuits is presented through the digital light processing(DLP)of ultraviolet-curable silver paste(UV-SP)with adjustable photocuring properties,enabling the successful preparation of micro-scaled conductive structure on the sharply skewed hook face.The minimum modeling depth and width of the cured silver paste can be well controlled to 10 and 88µm,respectively.Compared with traditional printing technology,the printing efficiency of complex patterns has increased by over 70%.The printed silver circuit demonstrates an exceptionally high electrical conductivity,reaching as high as 1.16×10^(7) S/m.Additionally,the UV-SP exhibits significant manufacturing efficiency and superior molding resolution compared to conventional direct ink writing and inkjet printing techniques,thereby contributing to the attainment of high precision and efficiency of conformal and micro-molding manufacturing in sensors,communication antennas,and other electronic devices based on curved substrates.展开更多
China has widely distributed silver deposits,and is rich in silver resources.Although silver deposits are mainly associated with Pb-Zn deposits,a number of independent silver deposits have also been discovered in rece...China has widely distributed silver deposits,and is rich in silver resources.Although silver deposits are mainly associated with Pb-Zn deposits,a number of independent silver deposits have also been discovered in recent years.Silver deposits include different types,such as submarine volcanism and continental volcanism related type,intrusion related type,and sedimentary related type.This study summarized the metallogenic regularity of China＇s silver deposits systematically based mainly on the data from 490 silver deposits.It is shown that submarine volcanic sedimentary type,continental volcanic or sub-volcanic type,skarn type,hydrothermal type（including vein type and stratabound type）,sedimentary metamorphic type,sedimentary type and regolith type should be regarded as the most important prediction types of silver deposit.A total of 32 silver mineralization belts and 111 silver concentration areas have been delineated.The map of ＂Spatial distribution of silver mineralization belts in China＂ and other series of maps finished in this study may provide a theoretical basis for the evaluation and prognosis of silver resources potential in China.展开更多
Silver nanoparticles(Ag NPs)have attracted attention in the field of biomaterials due to their excellent antibacterial property.However,the reducing and stabilizing agents used for the chemical reduction of Ag NPs are...Silver nanoparticles(Ag NPs)have attracted attention in the field of biomaterials due to their excellent antibacterial property.However,the reducing and stabilizing agents used for the chemical reduction of Ag NPs are usually toxic and may cause water pollution.In this work,Ag NPs(31.2 nm in diameter)were prepared using the extract of straw,an agricultural waste,as the reducing and stabilizing agent.Experimental analysis revealed that the straw extract contained lignin,the structure of which possesses phenolic hydroxyl and methoxy groups that facilitate the reduction of silver salts into Ag NPs.The surfaces of Ag NPs were negatively charged due to the encapsulation of a thin layer of lignin molecules that prevented their aggregation.After the prepared Ag NPs were added to the precursor solution of acrylamide,free radical polymerization was triggered without the need for extra heating or light irradiation,resulting in the rapid formation of an Ag NP-polyacrylamide composite hydrogel.The inhibition zone test proved that the composite hydrogel possessed excellent antibacterial ability due to the presence of Ag NPs.The prepared hydrogel may have potential applications in the fabrication of biomedical materials,such as antibacterial dressings.展开更多
The Zijinshan ore field located in southwestern Fujian Province,China,is a representative porphyry-epithermal ore system hosting diverse mineralization types(Mao et al.,2013).The ore field comprises of the Zijinshan h...The Zijinshan ore field located in southwestern Fujian Province,China,is a representative porphyry-epithermal ore system hosting diverse mineralization types(Mao et al.,2013).The ore field comprises of the Zijinshan highsulfidation Cu-Au deposit,the Luoboling porphyry Cu-Mo deposit,the transitional style Cu deposit(Longjiangting and Wuziqilong)and the Yueyang low-sulfidation Agpolymetallic deposit(Zhang,2013;Zhang et al.,2003)展开更多
A Silver-catalyzed enantioselective[3+2]cycloaddition of azomethine ylides with activated alkenes by using a P-stereogenic ligand Ganphos is reported.The method provides an efficient strategy for the effective synthes...A Silver-catalyzed enantioselective[3+2]cycloaddition of azomethine ylides with activated alkenes by using a P-stereogenic ligand Ganphos is reported.The method provides an efficient strategy for the effective synthesis of spirocyclic scaffolds containing a pyrroline motif.Notable features of this approach include good yields,remarkable enantioselectivity,as well as a broad substrate scope and significant step efficiency.展开更多
The potent antibacterial activity of silver nanoparticles is primarily attributed to the release of silver ions,which disrupt cell membranes and inactivate essential enzymes through Ag−S bonding formation.[Objective]T...The potent antibacterial activity of silver nanoparticles is primarily attributed to the release of silver ions,which disrupt cell membranes and inactivate essential enzymes through Ag−S bonding formation.[Objective]To explore silver ion immobilization to minimize silver release.[Methods]A macrocyclic cryptand with nitrogen bridgeheads was prepared and subsequently chelated with silver ions to produce Cage silver(I),which was then coordinated with different ratios of sulfonated chitosan(SCS)to form SCS/Cage Ag(I)complexes(SCA1,SCA2,and SCA3).The antioxidant activities of the complexes were assessed by reducing power and 1,1-diphenyl-2-picrylhydrazyl(DPPH)free radical and hydrogen peroxide scavenging assays.The antibacterial activities of the complexes were evaluated based on the minimum inhibitory concentrations(MICs)and minimum bactericidal concentrations(MBCs)against Staphylococcus aureus ATCC 6538 and Escherichia coli O157:H7 and the inhibition rate on biofilm formation.[Results]Cage silver(I)exhibited strong antibacterial activity,with the MIC of 0.015 mg/mL and MBC of 0.031 mg/mL against S.aureus ATCC 6538,and the MIC of 0.031 mg/mL and MBC of 0.120 mg/mL against E.coli O157:H7.Significant antioxidant properties of Cage silver(I)were also observed,as demonstrated by the DPPH free radical scavenging rates of 42.2%and 53.1%at 326 nm and 517 nm,respectively.Cage silver(I)exhibited the highest antibacterial and antioxidant activities,followed by SCA1,SCA2,SCA3,and SCS,because the content of silver ions in Cage silver(I)was 10-fold higher than that in SCA1.The antibacterial and antioxidant activities of SCA1 were better than those of Cage silver(I),which further indicated that the sulfonic groups of SCS may intensely coordinate with silver ions to exert synergistic effects.[Conclusion]Combining the merits of silver ions and SCS improves the bioavailability of the agent at microbicidal concentrations,minimizes the accumulation in the environment,and reduces treatment costs.The method developed herein offers a sustainable approach to enhance microbial control while minimizing the impact on the environment.展开更多
Herein,a one-pot chemical reduction method was reported to prepare folic acid(FA)-stabilized silver nanoclusters(FA@Ag NCs),in which FA,hydrazine hydrate,and silver nitrate were used as capping agent,reducing agent,an...Herein,a one-pot chemical reduction method was reported to prepare folic acid(FA)-stabilized silver nanoclusters(FA@Ag NCs),in which FA,hydrazine hydrate,and silver nitrate were used as capping agent,reducing agent,and precursor,respectively.Several technologies were employed to investigate the structures and optical properties of FA@Ag NCs,including transmission electron microscopy(TEM),X-ray photoelectron spectrometer(XPS),Fourier transform infrared spectrometer(FTIR),X-ray diffractometer(XRD),fluorescence spectrometer,and ultraviolet visible absorption spectrometer.FA@Ag NCs were suggested to be highly dispersed and spherical with a size of around 2.8 nm.Moreover,the maximum excitation and emission wavelengths of FA@Ag NCs were 370 and 447 nm,respectively.Under the optimal detection conditions,FA@Ag NCs could be used to effectively detect malachite green with the linear detection range of 0.5-200μmol·L^(-1).The detection limit was 0.084μmol·L^(-1).The fluorescence-quenching mechanism was ascribed to the static quenching.The detection system based on FA@AgNCs was successfully used for the detection of malachite green in actual samples with good accuracy and reproducibility.展开更多
Novel silver/silver molybdate（Ag/Ag2MoO4） composites with surface plasmon resonance（SPR）-enhanced photocatalytic performance were successfully fabricated via a facile one-pot hydrothermal route with the presence o...Novel silver/silver molybdate（Ag/Ag2MoO4） composites with surface plasmon resonance（SPR）-enhanced photocatalytic performance were successfully fabricated via a facile one-pot hydrothermal route with the presence of sodium dodecyl sulfate（SDS） in this study.The as prepared silver/silver molybdate（Ag/Ag2MoO4） composites were systematically characterized by X-ray diffraction（XRD）,scanning electron microscopy（SEM） and ultraviolet-visible diffuse reflectance absorption spectroscopy（DRS） in order to investigate their crystal structure,morphology and optical property as well.The photocatalytic activities of the composites were subsequently evaluated by their ability to degrade rhodamine B（RhB） under visible-light irradiation.Varies of controlled experiments were then carefully operated to gain a deep insight into the assembling of Ag/Ag2MoO4composites.It was found that preparation conditions such as pH,reaction time,and the amount of surfactant played important roles in the formation of composites with octahedral microstructures.And the composite obtained at 160 ℃ using 0.5 g of sodium dodecyl sulfate exhibited the highest photocatalytic performance under visible-light irradiation.Capture experiments were also conducted to clarify the function of different active species generated on the surface of Ag/Ag2MoO4during the photocatalytic process,in which both holes and ·OH radicals were found to play crucial role in photocatalytic removal of RhB under visible light irradiation.A possible photocatalytic mechanism of Ag/Ag2MoO4 was finally proposed on the basis of all the results to explain the higher photocatalytic activity of the octahedral Ag/Ag2MoO4 composites.It was inferred that the photoinduced ＂hot＂ electrons can quickly transfer from the Ag NPs to the conduction band of Ag2MoO4 and react with oxygen and H2O to generate a large quality of active radicals such as ·OH and ·O2^- because of the SPR effects.Besides,this SPR effects of Ag nanoparticles deposited on the surface of Ag2MoO4 can not only dramatically amplify its light absorption,especially in the visible region,but also promote the separation of photoexcited electron-hole pairs and effectively decrease electron-hole recombination.展开更多
Outdoor jackets are engineered to protect against extreme weather while ensuring comfort and safety. Key to this protection is the thermal properties, achieved through insulation materials like down feathers and synth...Outdoor jackets are engineered to protect against extreme weather while ensuring comfort and safety. Key to this protection is the thermal properties, achieved through insulation materials like down feathers and synthetic fibers, which trap heat and minimize heat loss. Resistance to wind, rain, and snow is provided by waterproof and windproof fabrics, while breathability allows moisture to escape, maintaining a comfortable microclimate. Air permeability and water resistance are essential for achieving this balance. This study examines two outdoor jacket prototypes with six material layers each. The outer layer (Layer 1) consists of 100% polyester coated with polyurethane for waterproofing. Inner layers (Layers 2, 3, and 6) use wool/cotton and wool/polyamide blends, offering insulation and moisture-wicking properties. Down feathers are used as the filling material, providing excellent warmth. Advanced materials like graphene and silver honeycomb fabrics were included to enhance thermal conductivity and regulate heat transfer. Performance testing focused on thermal conductivity, comfort (water and air permeability), and mechanical properties like tensile strength and tear resistance. Tests also assessed spray application and fastness to evaluate durability under environmental exposure. Results showed that jackets with silver-infused honeycomb fabrics had superior thermal conductivity, enabling better heat regulation and comfort in harsh conditions. The findings highlight the advantages of integrating silver honeycomb fabrics into outdoor jackets. These materials enhance insulation, thermal regulation, and overall comfort, making them ideal for high-performance designs. Incorporating such fabrics ensures functionality, durability, and user protection in extreme environments.展开更多
The main objective of the study was to prepare a highly active antimicrobial remedy by combining active agents such as tannic acid and silver nanoparticles,which are usually used separately.This was achieved by applyi...The main objective of the study was to prepare a highly active antimicrobial remedy by combining active agents such as tannic acid and silver nanoparticles,which are usually used separately.This was achieved by applying a coating of 11 alternating layers of an insoluble complex of tannic acid with polyvinyl alcohol on paper by the layerby-layer approach,on the surface of which uniformly distributed spherical silver nanoparticles of uniform size,mainly 20–30 nm,were synthesized by in situ reduction using tannic acid,which also acts as a stabilizer,or an external reducing agent,which prevented polyphenol oxidation.This gave an insight into which form-oxidized or reduced-ismore active against microorganisms.It was shown that sterilization was not required after the coating of the paper with tannic acid and silver nanoparticles.When combined,their activity against the studied bacteria-gram-negative Escherichia coli and gram-positive Staphylococcus aureus,as well as yeast Candida albicans was higher and lasting up to 7 days than when tannic acid and silver nanoparticles were used separately,indicating possible synergism in their action.展开更多
Objective:To develop chitosan-silver nanoparticles targeting Pseudomonas aeruginosa biofilms and verify their antibacterial performance through animal experiments.Methods:Chitosan,silver nitrate,glacial acetic acid,an...Objective:To develop chitosan-silver nanoparticles targeting Pseudomonas aeruginosa biofilms and verify their antibacterial performance through animal experiments.Methods:Chitosan,silver nitrate,glacial acetic acid,and other chemical reagents were used to synthesize chitosan-silver nanoparticles.The characterization,minimum inhibitory concentration,and biofilm inhibition rate of the chitosan-silver nanoparticles were tested.A total of 40 SD rats were randomly divided into four groups.After routine adaptive feeding,the control group received intraperitoneal injection of normal saline;the model group received intraperitoneal injection of Pseudomonas aeruginosa suspension;the positive group received intraperitoneal injection of Pseudomonas aeruginosa suspension mixed with ampicillin at a volume ratio of 1∶1;the observation group received intraperitoneal injection of Pseudomonas aeruginosa suspension mixed with chitosan-silver nanoparticles(at minimum inhibitory concentration)at a volume ratio of 1∶1.Bacterial load,inflammatory factors,and liver and kidney function indicators in tissues were observed and compared among the four groups on the 3^(rd)day after treatment.Results:When the concentration of chitosansilver nanoparticles reached 8μg/mL or above,the OD value of the experimental wells was close to that of the control wells,indicating that 8μg/mL was the minimum inhibitory concentration of the chitosan-silver nanoparticles;at concentrations of 8μg/mL or above,the biofilm inhibition rate was greater than 80%.The bacterial load in the observation group was significantly lower than that in the model and positive groups(P<0.05).The expression levels of interleukin-6,interferon-γ,and tumor necrosis factor-αin the observation group were significantly lower than those in the model and positive groups(P<0.05).There were no statistically significant differences in alanine aminotransferase,aspartate aminotransferase,blood urea nitrogen,and creatinine levels among the four groups(P>0.05).Conclusion:The chitosan-silver nanoparticles targeting Pseudomonas aeruginosa biofilms constructed in this study exhibit good antibacterial effects against Pseudomonas aeruginosa and have good safety.展开更多
Copper extraction from chalcopyrite is challenging,because acid dissolution is slow,occurring incongruently via a complex three-step reaction mechanism.Silver has been known to catalyse copper extraction from chalcopy...Copper extraction from chalcopyrite is challenging,because acid dissolution is slow,occurring incongruently via a complex three-step reaction mechanism.Silver has been known to catalyse copper extraction from chalcopyrite since the 1970's;yet the mechanism remains controversial.Microcharacterisation of experimental products obtained under optimal leaching conditions(50-150μm chalcopyrite grains in ferric/ferrous-sulfate solution with a redox potential around 500 mV vs.Ag/AgCl,approximately 1ppm Ag;[Ag]6.4×10^(−6)mol/L;70℃;4 days)highlights the heterogeneity of the reaction:µm-thick layers of a porous copper-sulfide with variable composition formed both in cracks within,and on the surface of the chalcopyrite grains.There is no evidence for formation of Ag-rich phases(Ag_(2)S_((s)),Ag_((s)^(0))).The fundamental three-step reaction mechanism remains the same with or without added silver;silver merely accelerates the initial dissolution step.An integrated model for the catalytic effect of silver is proposed that incorporates recent advances in the reactivity of sulfide minerals.The initial reaction follows a‘Fluid-Induced Solid State Diffusion Mechanism’,where diffusion of Fe in the chalcopyrite lattice is driven towards the surface by its rapid removal into solution,resulting in a Fe-deficient surface layer.The large Ag+ion,relative to Cu+/Fe3+,diffuses into this Fe-deficient surface layer and accelerates chalcopyrite dissolution in the subsequent step,whereby chalcopyrite is replaced by copper sulfides via an interface coupled dissolution reprecipitation reaction as a consequence of the sulfide-rich micro-environment at the mineral surface.Effective Ag+recycling is key to the catalytic effect of silver,and occurs as a result of the strong affinity of Ag+for bisulfide ligands accumulating at the surface of dissolving chalcopyrite.展开更多
In thefield of material sciences,nano-based formulations have attracted the attention of researchers,as they are highly suit-able for applications in differentfields.Conventionally,physical and chemical techniques have...In thefield of material sciences,nano-based formulations have attracted the attention of researchers,as they are highly suit-able for applications in differentfields.Conventionally,physical and chemical techniques have been employed to synthesize silver nanoparticles(AgNPs).However,they use hazardous and poisonous ingredients,which are toxic to human health and the environment.Therefore,it necessitates the development of an eco-friendly and economical method for the fabrication of silver nanoparticles.Biogenic AgNPs have been synthesized using plants and microorganisms due to the presence of reducing agents such as metabolites and enzymes in their extracts.The size,shape,and other properties of the biogenic AgNPs have been characterized using various biophysical techniques.AgNPs are widely used to treat infections and diseases in humans and plants.They have demonstrated antifungal and antibacterial activities and,therefore,have been applied in various therapeutic applications like the treatment of cancer,wound dressing,orthopedic and cardiovascular implants,and dental composites.Biogenic AgNPs have been applied for the remediation of environmental pollution,including that of water and air via the detoxification of synthetic dyes and other contaminants.They have improved seed germination and plant growth after application as nanofertilizers and nano-pesticides,as well as in masking the effects of stress.This review describes various biological routes used in the green synthesis of silver nanoparticles and their potential applications in agricultural,environmental,and medicalfields.展开更多
[Objectives]To observe the clinical efficacy of Mongolian medicine silver needle combined with cupping and bloodletting therapy in the treatment of cervical spondylotic radiculopathy(CSR).[Methods]A total of 120 patie...[Objectives]To observe the clinical efficacy of Mongolian medicine silver needle combined with cupping and bloodletting therapy in the treatment of cervical spondylotic radiculopathy(CSR).[Methods]A total of 120 patients diagnosed with CSR who received treatment at the International Mongolian Hospital of Inner Mongolia between October 2021 and October 2022 were selected and randomly divided into two groups:A test group and a control group,with 60 patients in each group.The patients in the test group received Mongolian medicine silver needle combined with cupping and bloodletting therapy,following the principles of syndrome differentiation in Mongolian medicine.In contrast,the patients in the control group received only the Mongolian medicine silver needle therapy.After treatment,the Mongolian medicine syndrome scores,visual analogue scale(VAS)scores,and total clinical therapeutic effects in the two groups of patients were compared both prior to and following the treatment.[Results]The improvement in VAS and Mongolian medicine syndrome scores in the test group was greater than that in the control group,with a statistically significant difference(P<0.05).The scores of the test group surpassed those of the control group,and this difference was also statistically significant(P<0.05).Furthermore,the overall therapeutic effect in the test group was 93.33%,which was markedly higher than 76.67%observed in the control group(P<0.05).[Conclusions]The therapeutic effect of Mongolian medicine silver needle combined with cupping and bloodletting therapy in the treatment of CSR is remarkable.This approach has demonstrated efficacy in alleviating patient pain and improving the functionality of the cervical vertebrae,thereby warranting clinical promotion and application.展开更多
The structural phase transitions and ferroelectric dynamics of lead-free AgNbO_(3)have attracted consid-erable attention owing to their potential in energy-storage device applications.Here,we examine the impact of Li+...The structural phase transitions and ferroelectric dynamics of lead-free AgNbO_(3)have attracted consid-erable attention owing to their potential in energy-storage device applications.Here,we examine the impact of Li+doping on the phase transitions and polarization behavior of(Ag_(1-x)Li_(x))NbO_(3)(x=0-7%)ceramics through comprehensive dielectric and ferroelectric analyses.Rietveld refinement reveals a Li+-induced phase transition from Pbcm to R3c,with x=5%and x=6%compositions near the morphotropic phase boundary(MPB).Dielectric anomalies identify key characteristic temperatures,supporting the con-struction of a low-field phase diagram.High-field studies uncover a direct relationship between phase structure and polarization behavior,culminating in a high-field phase diagram.Near-MPB compositions exhibit distinct structural states,elucidating the mechanisms of reversible and irreversible phase transi-tions.This work provides a comprehensive explanation of the evolution of hysteresis loop profiles,capturing their progression from double hysteresis loops to square loops and their subsequent reversion to double loops under varying electric field and temperature conditions.These temperature-composition(T-x)and temperature-electric field(T-E)phase diagrams provide a robust framework for understanding phase evolution,offering critical insights into optimizing AgNbO_(3)-based ceramics for advanced functional applications.展开更多
The mainstream silver recovery has problems such as resource waste,weak silver selectivity,and complicated operation.Here,self-propelled magnetic enhanced capture hydrogel(magnetic NbFeB/MXene/GO,MNMGH)was prepared by...The mainstream silver recovery has problems such as resource waste,weak silver selectivity,and complicated operation.Here,self-propelled magnetic enhanced capture hydrogel(magnetic NbFeB/MXene/GO,MNMGH)was prepared by self-crosslinking encapsulation method.MNMGH achieved high selectivity(K_(d)=23.31 mL/g)in the acidic range,and exhibited ultrahigh silver recovery capacity(1604.8 mg/g),which greatly improved by 66%with the assistance of in-situ magnetic field.The recovered silver crystals could be directly physically exfoliated,without acid/base additions.The selective sieving effect of adsorption,MNMGH preferentially adsorbed Ag(I),and then selectively reduced to Ag(0),realizing dual-selective recovery.The in-situ magnetic field enhanced selective adsorption by enhancing mass transfer,reactivity of oxygen-containing functional groups.Furthermore,density function theory simulations demonstrated that the in-situ magnetic field could lower the silver reduction reaction energy barrier to enhance the selective reduction.Three-drive synergy system(reduction drive,adsorption drive and magnetic drive)achieved ultrahigh silver recovery performance.This study pioneered an in-situ magnetic field assisted enhancement strategy for dual-selective(adsorption/reduction)recovery of precious metal silver,which provided new idea for low-carbon recovery of noble metal from industrial waste liquids.展开更多
Phalaenopsis orchids are economically important ornamental crops;however,their commercial micropropagation is often limited by poor rooting efficiency and inconsistent growth.In this study,we investigated the effects ...Phalaenopsis orchids are economically important ornamental crops;however,their commercial micropropagation is often limited by poor rooting efficiency and inconsistent growth.In this study,we investigated the effects of silver nanoparticles(Ag-NPs)on the in vitro regeneration and growth of Phalaenopsis cultivar 611B to determine the optimal concentration of Ag-NPs for improved micropropagation outcomes.Shoot tip explants(2–3 mm)—derived from protocorm-like bodies were cultured on a regeneration medium containing Hyponex(20:20:20 and 6.5:6.5:19),18 g/L sugar,2 g/L peptone,0.8 g/L activated charcoal,12.5 g/L potato extract,50 mL/L apple juice,and 10 mg/L 6-benzylaminopurine(6-BA),with varying concentrations of Ag-NPs(0,0.5,1.0,2.0,and 2.5 mg/L).After 10–12 weeks,shoot and root formation,plant height,fresh weight,leaf number,and chlorophyll contents were evaluated.At 1.0 mg/L Ag-NPs,shoot regeneration(5.4 vs.2.9 shoots per explant),root induction(2.1 vs.1.4 roots per explant),and shoot formation frequency(100%vs.55%)were significantly higher than the control(0 mg/L).Fresh weight(592.4 mg)and leaf number(9.7)also showed notable increases at this concentration.Although chlorophyll a and b levels peaked at 2.0 mg/L,the difference from 1.0 mg/L was not statistically significant.These results suggest that 1.0mg/LAg-NPs is the optimal concentration for enhancing shoot and root development and improving overall plantlet quality in Phalaenopsis.The findings highlight the potential of nanomaterials to improve the efficiency of orchid tissue culture systems.展开更多
基金the support from the National Key Research and Development Program of China (No. 2022YFC2904504)the Science and Technology Research Project of Jiangxi Provincial Department of Education, China (No. GJJ2200864)the Gansu Provincial Key Research and Development Project, China (No. 22YF7GA073)。
文摘The flotation separation of argentite from sphalerite using ammonium dibutyl dithiophosphate(ADD)was studied.Molecular simulation(MS)calculation shows that ADD is chemisorbed on argentite and sphalerite surface in the form of S—P bond.The ADD adsorption on argentite and sphalerite surface in Ag^(+)system was revealed by ICP,Zeta potential and XPS analyses.It is shown that the dissolved Ag^(+)from argentite surface can be absorbed on sphalerite surface in the form of silver hydroxide,and AgOH hydrophilic colloid prevents the adsorption of ADD on sphalerite surface.The ADD adsorption on argentite and sphalerite surface in the pulp containing silver and zinc ions was revealed by adsorption capacity and surface wettability analyses.It is shown that the combined Zn(OH)_(2) and AgOH hydrophilic colloid leads to greater ADD adsorption capacity on argentite surface and stronger surface hydrophobicity than sphalerite.Flotation tests demonstrate that ADD enables efficient separation of argentite from sphalerite in the pulp containing silver and zinc ions.
文摘“Are you dead?”It's not a morbid joke-it's the literal translation of the name of Chinese app Sileme,which went viral around the country in early January.However,amid public controversy over its unsettling connotations,the development team rebranded the app as Demumu on January 14,be-fore it was removed from the app stores of Apple and Android on January 15.
基金supported by the National Natural Science Foundation of China(Nos.51972079 and 52302062)the National Key Research and Development Program of China(Nos.2022YFB370630202 and 2022YFB3706305).
文摘Electronic 3D printing possesses a remarkable molding ability and convenience in integrated circuits,flexible wearables,and individual automobile requirements.However,traditional 3D printing technology still struggles to meet the demands of high precision and high efficiency in the process of fabricating a curved surface circuit,particularly achieving precise silver circuit molding on irregular substrates.Here,a high-precision and muti-scaled conformal manufacturing method for silver circuits is presented through the digital light processing(DLP)of ultraviolet-curable silver paste(UV-SP)with adjustable photocuring properties,enabling the successful preparation of micro-scaled conductive structure on the sharply skewed hook face.The minimum modeling depth and width of the cured silver paste can be well controlled to 10 and 88µm,respectively.Compared with traditional printing technology,the printing efficiency of complex patterns has increased by over 70%.The printed silver circuit demonstrates an exceptionally high electrical conductivity,reaching as high as 1.16×10^(7) S/m.Additionally,the UV-SP exhibits significant manufacturing efficiency and superior molding resolution compared to conventional direct ink writing and inkjet printing techniques,thereby contributing to the attainment of high precision and efficiency of conformal and micro-molding manufacturing in sensors,communication antennas,and other electronic devices based on curved substrates.
基金funded by the Chinese Geological Survey(Grant no.12120114039601,1212011121037,1212011220369)
文摘China has widely distributed silver deposits,and is rich in silver resources.Although silver deposits are mainly associated with Pb-Zn deposits,a number of independent silver deposits have also been discovered in recent years.Silver deposits include different types,such as submarine volcanism and continental volcanism related type,intrusion related type,and sedimentary related type.This study summarized the metallogenic regularity of China＇s silver deposits systematically based mainly on the data from 490 silver deposits.It is shown that submarine volcanic sedimentary type,continental volcanic or sub-volcanic type,skarn type,hydrothermal type（including vein type and stratabound type）,sedimentary metamorphic type,sedimentary type and regolith type should be regarded as the most important prediction types of silver deposit.A total of 32 silver mineralization belts and 111 silver concentration areas have been delineated.The map of ＂Spatial distribution of silver mineralization belts in China＂ and other series of maps finished in this study may provide a theoretical basis for the evaluation and prognosis of silver resources potential in China.
基金financially supported by the National Natural Science Foundation of China(No.52203209)the State Key Laboratory of Solid Waste Reuse for Building Materials,China(No.SWR-2022-009)the Fundamental Research Funds for the Central Universities,China(No.FRF-IDRY22-012)。
文摘Silver nanoparticles(Ag NPs)have attracted attention in the field of biomaterials due to their excellent antibacterial property.However,the reducing and stabilizing agents used for the chemical reduction of Ag NPs are usually toxic and may cause water pollution.In this work,Ag NPs(31.2 nm in diameter)were prepared using the extract of straw,an agricultural waste,as the reducing and stabilizing agent.Experimental analysis revealed that the straw extract contained lignin,the structure of which possesses phenolic hydroxyl and methoxy groups that facilitate the reduction of silver salts into Ag NPs.The surfaces of Ag NPs were negatively charged due to the encapsulation of a thin layer of lignin molecules that prevented their aggregation.After the prepared Ag NPs were added to the precursor solution of acrylamide,free radical polymerization was triggered without the need for extra heating or light irradiation,resulting in the rapid formation of an Ag NP-polyacrylamide composite hydrogel.The inhibition zone test proved that the composite hydrogel possessed excellent antibacterial ability due to the presence of Ag NPs.The prepared hydrogel may have potential applications in the fabrication of biomedical materials,such as antibacterial dressings.
基金financially supported by Zijin Mining Group(No.01612216)the Ministry of Natural Resources,China(No.ZKKJ202426)。
文摘The Zijinshan ore field located in southwestern Fujian Province,China,is a representative porphyry-epithermal ore system hosting diverse mineralization types(Mao et al.,2013).The ore field comprises of the Zijinshan highsulfidation Cu-Au deposit,the Luoboling porphyry Cu-Mo deposit,the transitional style Cu deposit(Longjiangting and Wuziqilong)and the Yueyang low-sulfidation Agpolymetallic deposit(Zhang,2013;Zhang et al.,2003)
文摘A Silver-catalyzed enantioselective[3+2]cycloaddition of azomethine ylides with activated alkenes by using a P-stereogenic ligand Ganphos is reported.The method provides an efficient strategy for the effective synthesis of spirocyclic scaffolds containing a pyrroline motif.Notable features of this approach include good yields,remarkable enantioselectivity,as well as a broad substrate scope and significant step efficiency.
文摘The potent antibacterial activity of silver nanoparticles is primarily attributed to the release of silver ions,which disrupt cell membranes and inactivate essential enzymes through Ag−S bonding formation.[Objective]To explore silver ion immobilization to minimize silver release.[Methods]A macrocyclic cryptand with nitrogen bridgeheads was prepared and subsequently chelated with silver ions to produce Cage silver(I),which was then coordinated with different ratios of sulfonated chitosan(SCS)to form SCS/Cage Ag(I)complexes(SCA1,SCA2,and SCA3).The antioxidant activities of the complexes were assessed by reducing power and 1,1-diphenyl-2-picrylhydrazyl(DPPH)free radical and hydrogen peroxide scavenging assays.The antibacterial activities of the complexes were evaluated based on the minimum inhibitory concentrations(MICs)and minimum bactericidal concentrations(MBCs)against Staphylococcus aureus ATCC 6538 and Escherichia coli O157:H7 and the inhibition rate on biofilm formation.[Results]Cage silver(I)exhibited strong antibacterial activity,with the MIC of 0.015 mg/mL and MBC of 0.031 mg/mL against S.aureus ATCC 6538,and the MIC of 0.031 mg/mL and MBC of 0.120 mg/mL against E.coli O157:H7.Significant antioxidant properties of Cage silver(I)were also observed,as demonstrated by the DPPH free radical scavenging rates of 42.2%and 53.1%at 326 nm and 517 nm,respectively.Cage silver(I)exhibited the highest antibacterial and antioxidant activities,followed by SCA1,SCA2,SCA3,and SCS,because the content of silver ions in Cage silver(I)was 10-fold higher than that in SCA1.The antibacterial and antioxidant activities of SCA1 were better than those of Cage silver(I),which further indicated that the sulfonic groups of SCS may intensely coordinate with silver ions to exert synergistic effects.[Conclusion]Combining the merits of silver ions and SCS improves the bioavailability of the agent at microbicidal concentrations,minimizes the accumulation in the environment,and reduces treatment costs.The method developed herein offers a sustainable approach to enhance microbial control while minimizing the impact on the environment.
文摘Herein,a one-pot chemical reduction method was reported to prepare folic acid(FA)-stabilized silver nanoclusters(FA@Ag NCs),in which FA,hydrazine hydrate,and silver nitrate were used as capping agent,reducing agent,and precursor,respectively.Several technologies were employed to investigate the structures and optical properties of FA@Ag NCs,including transmission electron microscopy(TEM),X-ray photoelectron spectrometer(XPS),Fourier transform infrared spectrometer(FTIR),X-ray diffractometer(XRD),fluorescence spectrometer,and ultraviolet visible absorption spectrometer.FA@Ag NCs were suggested to be highly dispersed and spherical with a size of around 2.8 nm.Moreover,the maximum excitation and emission wavelengths of FA@Ag NCs were 370 and 447 nm,respectively.Under the optimal detection conditions,FA@Ag NCs could be used to effectively detect malachite green with the linear detection range of 0.5-200μmol·L^(-1).The detection limit was 0.084μmol·L^(-1).The fluorescence-quenching mechanism was ascribed to the static quenching.The detection system based on FA@AgNCs was successfully used for the detection of malachite green in actual samples with good accuracy and reproducibility.
基金supported by Fundamental Research Funds for the Central Universities (2662014BQ061, 2015PY120, 2015PY047, 2016PY088)the National Natural Science Foundation of China (51572101, 21502059, 21607047)~~
文摘Novel silver/silver molybdate（Ag/Ag2MoO4） composites with surface plasmon resonance（SPR）-enhanced photocatalytic performance were successfully fabricated via a facile one-pot hydrothermal route with the presence of sodium dodecyl sulfate（SDS） in this study.The as prepared silver/silver molybdate（Ag/Ag2MoO4） composites were systematically characterized by X-ray diffraction（XRD）,scanning electron microscopy（SEM） and ultraviolet-visible diffuse reflectance absorption spectroscopy（DRS） in order to investigate their crystal structure,morphology and optical property as well.The photocatalytic activities of the composites were subsequently evaluated by their ability to degrade rhodamine B（RhB） under visible-light irradiation.Varies of controlled experiments were then carefully operated to gain a deep insight into the assembling of Ag/Ag2MoO4composites.It was found that preparation conditions such as pH,reaction time,and the amount of surfactant played important roles in the formation of composites with octahedral microstructures.And the composite obtained at 160 ℃ using 0.5 g of sodium dodecyl sulfate exhibited the highest photocatalytic performance under visible-light irradiation.Capture experiments were also conducted to clarify the function of different active species generated on the surface of Ag/Ag2MoO4during the photocatalytic process,in which both holes and ·OH radicals were found to play crucial role in photocatalytic removal of RhB under visible light irradiation.A possible photocatalytic mechanism of Ag/Ag2MoO4 was finally proposed on the basis of all the results to explain the higher photocatalytic activity of the octahedral Ag/Ag2MoO4 composites.It was inferred that the photoinduced ＂hot＂ electrons can quickly transfer from the Ag NPs to the conduction band of Ag2MoO4 and react with oxygen and H2O to generate a large quality of active radicals such as ·OH and ·O2^- because of the SPR effects.Besides,this SPR effects of Ag nanoparticles deposited on the surface of Ag2MoO4 can not only dramatically amplify its light absorption,especially in the visible region,but also promote the separation of photoexcited electron-hole pairs and effectively decrease electron-hole recombination.
文摘Outdoor jackets are engineered to protect against extreme weather while ensuring comfort and safety. Key to this protection is the thermal properties, achieved through insulation materials like down feathers and synthetic fibers, which trap heat and minimize heat loss. Resistance to wind, rain, and snow is provided by waterproof and windproof fabrics, while breathability allows moisture to escape, maintaining a comfortable microclimate. Air permeability and water resistance are essential for achieving this balance. This study examines two outdoor jacket prototypes with six material layers each. The outer layer (Layer 1) consists of 100% polyester coated with polyurethane for waterproofing. Inner layers (Layers 2, 3, and 6) use wool/cotton and wool/polyamide blends, offering insulation and moisture-wicking properties. Down feathers are used as the filling material, providing excellent warmth. Advanced materials like graphene and silver honeycomb fabrics were included to enhance thermal conductivity and regulate heat transfer. Performance testing focused on thermal conductivity, comfort (water and air permeability), and mechanical properties like tensile strength and tear resistance. Tests also assessed spray application and fastness to evaluate durability under environmental exposure. Results showed that jackets with silver-infused honeycomb fabrics had superior thermal conductivity, enabling better heat regulation and comfort in harsh conditions. The findings highlight the advantages of integrating silver honeycomb fabrics into outdoor jackets. These materials enhance insulation, thermal regulation, and overall comfort, making them ideal for high-performance designs. Incorporating such fabrics ensures functionality, durability, and user protection in extreme environments.
基金funded by the Russian Science Foundation,grant 22-13-00337.
文摘The main objective of the study was to prepare a highly active antimicrobial remedy by combining active agents such as tannic acid and silver nanoparticles,which are usually used separately.This was achieved by applying a coating of 11 alternating layers of an insoluble complex of tannic acid with polyvinyl alcohol on paper by the layerby-layer approach,on the surface of which uniformly distributed spherical silver nanoparticles of uniform size,mainly 20–30 nm,were synthesized by in situ reduction using tannic acid,which also acts as a stabilizer,or an external reducing agent,which prevented polyphenol oxidation.This gave an insight into which form-oxidized or reduced-ismore active against microorganisms.It was shown that sterilization was not required after the coating of the paper with tannic acid and silver nanoparticles.When combined,their activity against the studied bacteria-gram-negative Escherichia coli and gram-positive Staphylococcus aureus,as well as yeast Candida albicans was higher and lasting up to 7 days than when tannic acid and silver nanoparticles were used separately,indicating possible synergism in their action.
文摘Objective:To develop chitosan-silver nanoparticles targeting Pseudomonas aeruginosa biofilms and verify their antibacterial performance through animal experiments.Methods:Chitosan,silver nitrate,glacial acetic acid,and other chemical reagents were used to synthesize chitosan-silver nanoparticles.The characterization,minimum inhibitory concentration,and biofilm inhibition rate of the chitosan-silver nanoparticles were tested.A total of 40 SD rats were randomly divided into four groups.After routine adaptive feeding,the control group received intraperitoneal injection of normal saline;the model group received intraperitoneal injection of Pseudomonas aeruginosa suspension;the positive group received intraperitoneal injection of Pseudomonas aeruginosa suspension mixed with ampicillin at a volume ratio of 1∶1;the observation group received intraperitoneal injection of Pseudomonas aeruginosa suspension mixed with chitosan-silver nanoparticles(at minimum inhibitory concentration)at a volume ratio of 1∶1.Bacterial load,inflammatory factors,and liver and kidney function indicators in tissues were observed and compared among the four groups on the 3^(rd)day after treatment.Results:When the concentration of chitosansilver nanoparticles reached 8μg/mL or above,the OD value of the experimental wells was close to that of the control wells,indicating that 8μg/mL was the minimum inhibitory concentration of the chitosan-silver nanoparticles;at concentrations of 8μg/mL or above,the biofilm inhibition rate was greater than 80%.The bacterial load in the observation group was significantly lower than that in the model and positive groups(P<0.05).The expression levels of interleukin-6,interferon-γ,and tumor necrosis factor-αin the observation group were significantly lower than those in the model and positive groups(P<0.05).There were no statistically significant differences in alanine aminotransferase,aspartate aminotransferase,blood urea nitrogen,and creatinine levels among the four groups(P>0.05).Conclusion:The chitosan-silver nanoparticles targeting Pseudomonas aeruginosa biofilms constructed in this study exhibit good antibacterial effects against Pseudomonas aeruginosa and have good safety.
基金supporting this work through an ARC linkage grant(LP190101230)Part of this work was funded by ARC DP220100500+2 种基金The authors acknowledge the use of the instruments and scientific and technical assistance at the Monash Centre for Electron Microscopy,Monash University,a Microscopy Australia(ROR:042mm0k03)facility supported by NCRISThis research used equipment funded by Australian Research Council grant(s)(LE200100132,LE110100223).
文摘Copper extraction from chalcopyrite is challenging,because acid dissolution is slow,occurring incongruently via a complex three-step reaction mechanism.Silver has been known to catalyse copper extraction from chalcopyrite since the 1970's;yet the mechanism remains controversial.Microcharacterisation of experimental products obtained under optimal leaching conditions(50-150μm chalcopyrite grains in ferric/ferrous-sulfate solution with a redox potential around 500 mV vs.Ag/AgCl,approximately 1ppm Ag;[Ag]6.4×10^(−6)mol/L;70℃;4 days)highlights the heterogeneity of the reaction:µm-thick layers of a porous copper-sulfide with variable composition formed both in cracks within,and on the surface of the chalcopyrite grains.There is no evidence for formation of Ag-rich phases(Ag_(2)S_((s)),Ag_((s)^(0))).The fundamental three-step reaction mechanism remains the same with or without added silver;silver merely accelerates the initial dissolution step.An integrated model for the catalytic effect of silver is proposed that incorporates recent advances in the reactivity of sulfide minerals.The initial reaction follows a‘Fluid-Induced Solid State Diffusion Mechanism’,where diffusion of Fe in the chalcopyrite lattice is driven towards the surface by its rapid removal into solution,resulting in a Fe-deficient surface layer.The large Ag+ion,relative to Cu+/Fe3+,diffuses into this Fe-deficient surface layer and accelerates chalcopyrite dissolution in the subsequent step,whereby chalcopyrite is replaced by copper sulfides via an interface coupled dissolution reprecipitation reaction as a consequence of the sulfide-rich micro-environment at the mineral surface.Effective Ag+recycling is key to the catalytic effect of silver,and occurs as a result of the strong affinity of Ag+for bisulfide ligands accumulating at the surface of dissolving chalcopyrite.
文摘In thefield of material sciences,nano-based formulations have attracted the attention of researchers,as they are highly suit-able for applications in differentfields.Conventionally,physical and chemical techniques have been employed to synthesize silver nanoparticles(AgNPs).However,they use hazardous and poisonous ingredients,which are toxic to human health and the environment.Therefore,it necessitates the development of an eco-friendly and economical method for the fabrication of silver nanoparticles.Biogenic AgNPs have been synthesized using plants and microorganisms due to the presence of reducing agents such as metabolites and enzymes in their extracts.The size,shape,and other properties of the biogenic AgNPs have been characterized using various biophysical techniques.AgNPs are widely used to treat infections and diseases in humans and plants.They have demonstrated antifungal and antibacterial activities and,therefore,have been applied in various therapeutic applications like the treatment of cancer,wound dressing,orthopedic and cardiovascular implants,and dental composites.Biogenic AgNPs have been applied for the remediation of environmental pollution,including that of water and air via the detoxification of synthetic dyes and other contaminants.They have improved seed germination and plant growth after application as nanofertilizers and nano-pesticides,as well as in masking the effects of stress.This review describes various biological routes used in the green synthesis of silver nanoparticles and their potential applications in agricultural,environmental,and medicalfields.
基金Supported by Project of Science and Technology Department of Inner Mongolia Autonomous Region(2019GG125).
文摘[Objectives]To observe the clinical efficacy of Mongolian medicine silver needle combined with cupping and bloodletting therapy in the treatment of cervical spondylotic radiculopathy(CSR).[Methods]A total of 120 patients diagnosed with CSR who received treatment at the International Mongolian Hospital of Inner Mongolia between October 2021 and October 2022 were selected and randomly divided into two groups:A test group and a control group,with 60 patients in each group.The patients in the test group received Mongolian medicine silver needle combined with cupping and bloodletting therapy,following the principles of syndrome differentiation in Mongolian medicine.In contrast,the patients in the control group received only the Mongolian medicine silver needle therapy.After treatment,the Mongolian medicine syndrome scores,visual analogue scale(VAS)scores,and total clinical therapeutic effects in the two groups of patients were compared both prior to and following the treatment.[Results]The improvement in VAS and Mongolian medicine syndrome scores in the test group was greater than that in the control group,with a statistically significant difference(P<0.05).The scores of the test group surpassed those of the control group,and this difference was also statistically significant(P<0.05).Furthermore,the overall therapeutic effect in the test group was 93.33%,which was markedly higher than 76.67%observed in the control group(P<0.05).[Conclusions]The therapeutic effect of Mongolian medicine silver needle combined with cupping and bloodletting therapy in the treatment of CSR is remarkable.This approach has demonstrated efficacy in alleviating patient pain and improving the functionality of the cervical vertebrae,thereby warranting clinical promotion and application.
基金finically supported by the National Natural Science Foundation of China(Nos.52261135548,52302153,and 52402155)the China Postdoctoral Science Foundation(Nos.GZC20232075 and 2023M742767)+2 种基金The research was made possible by Russian Science Foundation(Project No 23-42-00116)The equipment of the Ural Center for Shared Use“Modern nanotech-nology”Ural Federal University(Reg.No2968)whichis supported by the Ministry of Science and Higher Education RF(Project No 075-15-2021-677)was usedThe SEM work was done at International Center for Dielectric Research(ICDR),Xi’an Jiaotong University,Xi’an,China.
文摘The structural phase transitions and ferroelectric dynamics of lead-free AgNbO_(3)have attracted consid-erable attention owing to their potential in energy-storage device applications.Here,we examine the impact of Li+doping on the phase transitions and polarization behavior of(Ag_(1-x)Li_(x))NbO_(3)(x=0-7%)ceramics through comprehensive dielectric and ferroelectric analyses.Rietveld refinement reveals a Li+-induced phase transition from Pbcm to R3c,with x=5%and x=6%compositions near the morphotropic phase boundary(MPB).Dielectric anomalies identify key characteristic temperatures,supporting the con-struction of a low-field phase diagram.High-field studies uncover a direct relationship between phase structure and polarization behavior,culminating in a high-field phase diagram.Near-MPB compositions exhibit distinct structural states,elucidating the mechanisms of reversible and irreversible phase transi-tions.This work provides a comprehensive explanation of the evolution of hysteresis loop profiles,capturing their progression from double hysteresis loops to square loops and their subsequent reversion to double loops under varying electric field and temperature conditions.These temperature-composition(T-x)and temperature-electric field(T-E)phase diagrams provide a robust framework for understanding phase evolution,offering critical insights into optimizing AgNbO_(3)-based ceramics for advanced functional applications.
基金supported by The National Natural Science Foundation of China(52170087,22276137).
文摘The mainstream silver recovery has problems such as resource waste,weak silver selectivity,and complicated operation.Here,self-propelled magnetic enhanced capture hydrogel(magnetic NbFeB/MXene/GO,MNMGH)was prepared by self-crosslinking encapsulation method.MNMGH achieved high selectivity(K_(d)=23.31 mL/g)in the acidic range,and exhibited ultrahigh silver recovery capacity(1604.8 mg/g),which greatly improved by 66%with the assistance of in-situ magnetic field.The recovered silver crystals could be directly physically exfoliated,without acid/base additions.The selective sieving effect of adsorption,MNMGH preferentially adsorbed Ag(I),and then selectively reduced to Ag(0),realizing dual-selective recovery.The in-situ magnetic field enhanced selective adsorption by enhancing mass transfer,reactivity of oxygen-containing functional groups.Furthermore,density function theory simulations demonstrated that the in-situ magnetic field could lower the silver reduction reaction energy barrier to enhance the selective reduction.Three-drive synergy system(reduction drive,adsorption drive and magnetic drive)achieved ultrahigh silver recovery performance.This study pioneered an in-situ magnetic field assisted enhancement strategy for dual-selective(adsorption/reduction)recovery of precious metal silver,which provided new idea for low-carbon recovery of noble metal from industrial waste liquids.
文摘Phalaenopsis orchids are economically important ornamental crops;however,their commercial micropropagation is often limited by poor rooting efficiency and inconsistent growth.In this study,we investigated the effects of silver nanoparticles(Ag-NPs)on the in vitro regeneration and growth of Phalaenopsis cultivar 611B to determine the optimal concentration of Ag-NPs for improved micropropagation outcomes.Shoot tip explants(2–3 mm)—derived from protocorm-like bodies were cultured on a regeneration medium containing Hyponex(20:20:20 and 6.5:6.5:19),18 g/L sugar,2 g/L peptone,0.8 g/L activated charcoal,12.5 g/L potato extract,50 mL/L apple juice,and 10 mg/L 6-benzylaminopurine(6-BA),with varying concentrations of Ag-NPs(0,0.5,1.0,2.0,and 2.5 mg/L).After 10–12 weeks,shoot and root formation,plant height,fresh weight,leaf number,and chlorophyll contents were evaluated.At 1.0 mg/L Ag-NPs,shoot regeneration(5.4 vs.2.9 shoots per explant),root induction(2.1 vs.1.4 roots per explant),and shoot formation frequency(100%vs.55%)were significantly higher than the control(0 mg/L).Fresh weight(592.4 mg)and leaf number(9.7)also showed notable increases at this concentration.Although chlorophyll a and b levels peaked at 2.0 mg/L,the difference from 1.0 mg/L was not statistically significant.These results suggest that 1.0mg/LAg-NPs is the optimal concentration for enhancing shoot and root development and improving overall plantlet quality in Phalaenopsis.The findings highlight the potential of nanomaterials to improve the efficiency of orchid tissue culture systems.
