Available onlineSilicon monoxide(SiO)is a promising anode material fo r lithium-ion batteries(LIBs)due to its high theoretical specific capacity(~2400 mAh/g),low working potential(<0.5 V vs.Li^+/Li),low cost,easy s...Available onlineSilicon monoxide(SiO)is a promising anode material fo r lithium-ion batteries(LIBs)due to its high theoretical specific capacity(~2400 mAh/g),low working potential(<0.5 V vs.Li^+/Li),low cost,easy synthesis,nontoxicity,abundant natural source and smaller volume expansion than Si.However,low intrinsic electrical conductivity,low initial Coulombic efficiency(ICE)and inevitable volume expansion(~200%)impede its practical application.Here we fabricate SiO/wrinkled MXene composite(SiO-WM)by an electrostatic self-assembly method.Importantly,this method is simple,scalable and taking into account all the issues of SiO.As a result,the SiO-WM exhibits imp roved rate capability,cycling performance and ICE than bare SiO.展开更多
Constructing electrode materials with large capacity and good conductivity is an effective approach to improve the capacitor performance of asymmetric supercapacitors(ASCs).In this paper,ZnCo_(2)S_(4)core-shell nanosp...Constructing electrode materials with large capacity and good conductivity is an effective approach to improve the capacitor performance of asymmetric supercapacitors(ASCs).In this paper,ZnCo_(2)S_(4)core-shell nanospheres are constructed by two-step hydrothermal method.In order to improve the chemical activity of ZnCo_(2)S_(4),ZnCo_(2)S_(4)is activated using cetyltrimethylammonium bromide(CTAB).Then,MXene nanosheets are fixed on the surface of ZnCo_(2)S_(4)by electrostatic selfassembly method to improve the specific surface area of ZnCo_(2)S_(4)and MXene-wrapped ZnCo_(2)S_(4)composite is prepared in this work.Owing to the synergy effect between MXene nanosheets and ZnCo_(2)S_(4)core-shell nanospheres,the as-prepared composite displays fast ion transfer rate and charge/discharge process.The capacity of the MXenewrapped ZnCo_(2)S_(4)composite can reach 1072 F·g^(-1),which is far larger than that of ZnCo_(2)S_(4)(407 F·g^(-1))at 1 A·g^(-1).An ASC device is assembled,which delivers 1.7 V potential window and superior cyclic stability(95.41%capacitance retention).Furthermore,energy density of this device is up to 30.46 Wh·kg^(-1)at a power density of850 W·kg^(-1).The above results demonstrate that MXenewrapped ZnCo_(2)S_(4)composite has great application prospects in electrochemical energy storage field.展开更多
Electrostatic self-assembly method （ESAM） was used to prepare bentonite supported-nano titanium dioxide photocatalysts. The materials were characterized by X-ray diffraction （XRD）, fourier transform infrared spect...Electrostatic self-assembly method （ESAM） was used to prepare bentonite supported-nano titanium dioxide photocatalysts. The materials were characterized by X-ray diffraction （XRD）, fourier transform infrared spectroscopy （FT-IR） and scanning electron microscopy （SEM）. Methyl orange was used to estimate the photocatalytic activity of the materials. The effects of the calcination temperature and silane dosage on the photocatalytic activity of the samples were investigated. The experimental results show that the bentonite facilitates the formation of anatase and restrains the transformation of anatase to rutile. Part of nano-size TiO2 particles insert into the galleries of bentonite. The photocatalysts exhibit a synergistic effect of adsorption and photocatalysis on methyl orange. Photocatalysts prepared by ESAM method exhibit higher photocatalytic activity and better recycle ability than those of the traditional method.展开更多
Anionic surfactant sodium lauryl sulfate(SDS), cationic surfactant palmityl trimethyl ammonium chloride(CTAC) and TiO_2 were used to prepare multilayer films on quartz optic fibers by the electrostatic self-assembly (...Anionic surfactant sodium lauryl sulfate(SDS), cationic surfactant palmityl trimethyl ammonium chloride(CTAC) and TiO_2 were used to prepare multilayer films on quartz optic fibers by the electrostatic self-assembly (ESA) method. The whole self-assemble process, the function of surfactant and the effect of TiO_2 slurry′s concentration to the self-assemble were discussed. The isoelectric point of TiO_2 slurry measured by experiment is 6.8. The results show that whatever the concentration of the TiO_2 dispersion, a flat and compact adsorbed monolayer on the optic fiber can be built in a stable dispersion at lower pH. There is a adsorbed equilibrium on the substrate (fiber)/solution interface when enough time of incubation is given. A rough and loosen adsorbed layer is formed on the fiber surface by immersed the substrate in a high pH dispersion (pH>10) because the presence of hydroxyl on particle surface. Film thickness can be controlled by controlling the number of layers in the film.展开更多
Gold colloids were prepared by citrate-induced reduction of hydrogen tetrachloroaurale, and gold nanoparticles were electrostatically self-assembled with poly( diallyldimethylammonium chloride) into multi-layer thin f...Gold colloids were prepared by citrate-induced reduction of hydrogen tetrachloroaurale, and gold nanoparticles were electrostatically self-assembled with poly( diallyldimethylammonium chloride) into multi-layer thin films on si/icon and quartz substrates. The paniculate thin films were characterized by UV-vis spea-troscopy, surface, enhanced Raman scattering, atomic force microscopy and resistivity measurements. Due to the interparticle coupling between individual gold particles, an obvious collective particle plasmon resonance was ob-served on UV-vis spectra , and the particulate thin films exhibited a strong SERS effect. For multilayer thin films with a high particle coverage on substrates , resistivity of the order of 10-4 Ω·cm was yielded.展开更多
Aqueous zinc ion batteries have become highly favored energy storage devices owing to low cost and environmental friendliness.Vanadium oxide,as one of the potential cathodes for AZIBs,is plagued by several unfavorable...Aqueous zinc ion batteries have become highly favored energy storage devices owing to low cost and environmental friendliness.Vanadium oxide,as one of the potential cathodes for AZIBs,is plagued by several unfavorable elements including unsatisfactory conductivity and vanadium dissolution in the electrolyte.Herein,an electrostatic self-assembly strategy is proposed to introduce conductive dielectric Ti_(3)C_(2)T_(x)MXene nanoplates into V_(2)O_(5)·4VO_(2)nanoribbons,where V_(2)O_(5)·4VO_(2)/MXene composites(denoted as VM2)are simply obtained by magnetic stirring combined with ultrasonic method at room temperature.The successful introduction of MXene with high electrical conductivity not only endows faster V_(2)O_(5)·4VO_(2)electron/ion transfer,but also acts as a"baffle"to inhibit vanadium dissolution.Benefiting from the above advantages,paired with a zinc metal anode,VM2 cathode exhibits impressive performance metrics of 328.7 mAh·g^(−1)at 0.1 A·g^(−1),95.8%capacity retention after 1000 cycles,and 142.9 mAh·g^(−1)at a current density of 20 A·g^(−1).This work provides a viable reference for the development of high-performance AZIBs.展开更多
Low patency ratio of small-diameter vascular grafts remains a major challenge due to the occurrence of thrombosis formation and intimal hyperplasia after transplantation.Although developing the functional coating with...Low patency ratio of small-diameter vascular grafts remains a major challenge due to the occurrence of thrombosis formation and intimal hyperplasia after transplantation.Although developing the functional coating with release of bioactive molecules on the surface of small-diameter vascular grafts are reported as an effective strategy to improve their patency ratios,it is still difficult for current functional coatings cooperating with spatiotemporal control of bioactive molecules release to mimic the sequential requirements for antithrombogenicity and endothelialization.Herein,on basis of 3D-printed polyelectrolyte-based vascular grafts,a biologically inspired release system with sequential release in spatiotemporal coordination of dual molecules through an electrostatic self-assembly was first described.A series of tubes with tunable diameters were initially fabricated by a coaxial extrusion printing method with customized nozzles,in which a polyelectrolyte ink containing of ε-polylysine and sodium alginate was used.Further,dual bioactive molecules,heparin with negative charges and Tyr-Ile-Gly-Ser-Arg(YIGSR)peptide with positive charges were layer-by-layer assembled onto the surface of these 3D-printed tubes.Due to the electrostatic interaction,the sequential release of heparin and YIGSR was demonstrated and could construct a dynamic microenvironment that was thus conducive to the antithrombogenicity and endothelialization.This study opens a new avenue to fabricate a small-diameter vascular graft with a biologically inspired release system based on electrostatic interaction,revealing a huge potential for development of small-diameter artificial vascular grafts with good patency.展开更多
High-performance epoxy(EP)composites with excellent thermal conductivity and dielectric properties have attracted increasing attention for effective thermal management.In this work,three-dimensional(3D)structural func...High-performance epoxy(EP)composites with excellent thermal conductivity and dielectric properties have attracted increasing attention for effective thermal management.In this work,three-dimensional(3D)structural functional fillers were prepared by an electrostatic self-assembly approach.The negatively charged carbon nanotubes(nCNTs)prepared by carboxylation on the surface of CNTs were attached to the positively charged boron nitride(pBN)to form the 3D pBN@nCNTs functional fillers.The morphological characterizations of the formed 3D pBN@nCNTs fillers and epoxy composites were established,illustrating that nCNTs were linearly overlapped between the BN sheets,thus forming a 3D heat conduction network in the epoxy matrix.The synergistic effect of pBN with nCNTs on the enhancement of thermal conductivity and dielectric properties of composites was systematically studied.The experimental results demonstrated that the thermal conductivity of pBN@nCNTs/EP composites could reach 1.986 W m1K1 with the loading of 50 wt%fillers at 10:1 mass ratio of pBN:nCNTs,which is 464%and 124%higher than that of pure EP and BN/EP,respectively.Simultaneously,the dielectric permittivity was successfully increased to 15.14.Moreover,the thermal stability of the composites was synchronously enhanced.This study provides a facile path to fabricate thermosetting polymer composites with high thermal conductivity and dielectric properties.展开更多
Recently,hollow carbon nanospheres(HCSs)have garnered significant attention as potential Li metal hosts owing to their unique large voids and ease of fabrication.However,similar to other nanoscale hosts,their practica...Recently,hollow carbon nanospheres(HCSs)have garnered significant attention as potential Li metal hosts owing to their unique large voids and ease of fabrication.However,similar to other nanoscale hosts,their practical performance is limited by inhomogeneous agglomeration,increased binder requirements,and high tortuosity within the electrode.To overcome these problems and high tortuosity within the electrode,this study introduces a pomegranate-like carbon microcluster composed of primary HCSs(P-CMs)as a novel Li metal host.This unique nanostructure can be easily prepared using the spray-drying technique,enabling its mass production.Comprehensive analyses with various tools demonstrate that compared with HCS hosts,the P-CM host requires a smaller amount of binder to fabricate a sufficiently robust and even surface electrode.Furthermore,owing to reduced tortuosity,the well-designed P-CM electrode can provide continuous and shortened pathways for electron/ion transport,accelerating the Li-ion transfer kinetics and prohibiting preferential Li plating at the upper region of the electrode.Due to these characteristics,Li metal can be effectively encapsulated in the large inner voids of the primary HCSs constituting the P-CM,thereby enhancing the electrochemical performance of P-CM hosts in Li metal batteries.Specifically,the Coulombic efficiency of the P-CM host can be maintained at 97%over 100 cycles,with a high Li deposition areal capacity of 3 mAh·cm^(-2)and long cycle life(1000 h,1 mA·cm^(-2),and 1.0 mAh·cm^(-2)).Furthermore,a full cell incorporating a LiFePO4 cathode exhibits excellent cycle life.展开更多
Four glycoluril-based amphiphilic molecular clips(AMCs)M1~M4 have been prepared for intracellular delivery of short DNA.M1~M4 have two methyl groups on its convex surface and four cations on its aromatic side arm,whic...Four glycoluril-based amphiphilic molecular clips(AMCs)M1~M4 have been prepared for intracellular delivery of short DNA.M1~M4 have two methyl groups on its convex surface and four cations on its aromatic side arm,which can be used to construct self-assembled nanoparticles in aqueous solution driven by hydrophobic interaction.Dynamic light scattering experiments show that M1 and M2 can be driven hydrophobically to aggregate into extremely stable nanoparticles in water at the micromolar concentrations.Fluorescence titration and zeta potential experiments support that the nanoparticles formed by M1 and M2 are able to efficiently encapsulate short DNA(sDNA).Fluorescence imaging and flow cytometry studies reveal that their nano sizes enable intracellular delivery of the encapsulated sDNA into both normal and cancer cells,with delivery percentage reaching up to 94%,while in vitro experiments indicate that the two compounds have excellent biocompatibility and low cytotoxicity.展开更多
To study the influence of silicon(Si)on 2,4,6,8,10,12-hexanitro-2,4,6,8,10,12-hexaazaisowurtzitane(CL-20),NC/CL-20 composite explosives and Si/NC/CL-20 composite explosives were prepared by the electrostatic spraying ...To study the influence of silicon(Si)on 2,4,6,8,10,12-hexanitro-2,4,6,8,10,12-hexaazaisowurtzitane(CL-20),NC/CL-20 composite explosives and Si/NC/CL-20 composite explosives were prepared by the electrostatic spraying method.The morphology,structure and thermal decomposition properties of the samples were analyzed using scanning electron microscopy(SEM),X-ray energy spectroscopy(EDS),infrared spectroscopy(FT-IR),and simultaneous thermal analyzer(TG-DSC).Additionally,the combustion process of the samples was tested using a high-speed camera.The results show that the addition of nano-Si contributes to the formation of composite explosives with regular morphology and smaller particle size.The Si/NC/CL-20 composite explosive has better and more uniform sphericity,with an average particle size of 73.4 nm,compared to the NC/CL-20 composite explosive.The Si/NC/CL-20 composite explosive which produced by the electrostatic spraying method,achieves physically uniform distribution of the components including NC,CL-20,Si.The addition of Si promotes the thermal decomposition of CL-20.In comparison to the NC/CL-20 composite explosive,the activation energy of the Si/NC/CL-20 composite explosive decreases by 16.78 kJ/mol,and the self-accelerated decomposition temperature and the critical temperature of thermal explosion decreases by 3.12 K and 2.61 K,respectively.Furthermore,Si/NC/CL-20 composite explosive has shorter ignition delay time and faster combustion rate compared to the NC/CL-20 composite explosive,which shows that Si can improve the combustion performance of CL-20.展开更多
To explore the electrostatic discharge behavior of charged powders in industrial silos,discharge experiments are conducted based on a full-size industrial silo discharge platform.Electrostatic discharge mode,frequency...To explore the electrostatic discharge behavior of charged powders in industrial silos,discharge experiments are conducted based on a full-size industrial silo discharge platform.Electrostatic discharge mode,frequency,and energy are investigated for powders of different polarities.Although the powders have low charge-to-mass ratios(+0.087μC/kg for the positively charged powders and−0.26μC/kg for the negatively charged ones),electrostatic discharges occur approximately every 10 s,with the maximum discharge energy being 800 mJ.Powder polarity considerably influences discharge energy.The positive powders exhibit higher discharge energy than the negative ones,although discharge frequency remains similar for both.Effects of powder charge,humidity,and mass flow on discharge frequency and discharge energy are quantitatively analyzed,providing important insights for the improvement of safety in industrial powder handling.展开更多
Nowadays,high-stable and ultrasensitive heavy metal detection is of utmost importance in water quality monitoring.Nanoparticle-enhanced laser-induced breakdown spectroscopy(NELIBS)shows high potential in hazardous met...Nowadays,high-stable and ultrasensitive heavy metal detection is of utmost importance in water quality monitoring.Nanoparticle-enhanced laser-induced breakdown spectroscopy(NELIBS)shows high potential in hazardous metal detection,however,encounters unstable and weak signals due to nonuniform distribution of analytes.Herein,we developed an interface self-assembly(ISA)method to create a uniformly distributed gold nanolayer at a liquid-liquid interface for positive heavy metal ions capture and NELIBS analysis.The electrostatically selfassembled Au nanoparticles(NPs)-analytes membrane was prepared at the oil-water interface by injecting ethanol into the mixture of cyclohexane and Au NPs-analytes water solution.Then,the interface self-assembled Au NPs-analytes membrane was transformed onto a laser-processed superhydrophilic Si slide for detection.Three heavy metals(cadmium(Cd),barium(Ba),and chromium(Cr))were analyzed to evaluate the stability and sensitivity of the ISA method for NELIBS.The results(Cd:RSD=3.6%,LoD=0.654 mg/L;Ba:RSD=3.4%,LoD=0.236 mg/L;Cr:RSD=7.7%,LoD=1.367 mg/L)demonstrated signal enhancement and high-stable and ultrasensitive detection.The actual sample detection(Cd:RE=7.71%,Ba:RE=6.78%)illustrated great reliability.The ISA method,creating a uniform distribution of NP-analytes at the interface,has promising prospects in NELIBS.展开更多
Diphenylalanine and its analogs cause many concerns owing to their perfect self-assembly properties in the fields of biology,medicine,and nanotechnology.Experimental research has shown that diphenylalanine-based analo...Diphenylalanine and its analogs cause many concerns owing to their perfect self-assembly properties in the fields of biology,medicine,and nanotechnology.Experimental research has shown that diphenylalanine-based analogs with ethylenediamine linkers(PA,P=phenylalanine,and A=analog)can self-assemble into spherical assemblies,which can serve as novel anticancer drug carriers.In this work,to understand the assembly pathways,drug loading behavior,and formation mechanism of PA aggregates at the molecular level,we carried out dissipative particle dynamics(DPD)simulations of PA molecule systems.Our simulation results demonstrate that PA molecules spontaneously assemble into nanospheres and can self-assemble into drug-loaded nanospheres upon addition of the cancer chemotherapeutic agent doxorubicin(DOX).We also found that the hydrophobic side chain beads of PA molecules exhibited a unique onion-like distribution inside the nanospheres,which was not observed in the experiment.The onion-like nanospheres were verified by calculating the radial distribution function(RDF)of the DPD beads.Furthermore,based on the analysis of the percentages of different interaction components in the total nonbonded energies,main chain-side chain interactions between PA molecules may be important in the formation of onion-like nanospheres,and the synergistic effects of main chain-side chain,main chain-drug,side chain-drug,and main chain-solvent interactions are significant in the formation of drug-loaded nanospheres.These findings provide new insights into the structure and self-assembly pathway of PA assemblies,which may be helpful for the design of efficient and effective drug delivery systems.展开更多
The liquid Zr_(100-x)V_(x)(x=8.6,16.5,30)alloys were undercooled to the maximum undercooling of 364 K(0.18 T_(L)),405 K(0.21 T_(L)),and 375 K(0.21 T_(L)),respectively,by using electrostatic levitation technique.The Zr...The liquid Zr_(100-x)V_(x)(x=8.6,16.5,30)alloys were undercooled to the maximum undercooling of 364 K(0.18 T_(L)),405 K(0.21 T_(L)),and 375 K(0.21 T_(L)),respectively,by using electrostatic levitation technique.The Zr_(91.4)V_(8.6) and Zr_(83.5)V_(16.5) alloys present only one recalescence during liquid/solid phase transition,while the Zr_(70)V_(30) alloy presents a transformation from two recalescence to one recalescence phenomenon with a critical undercooling of approximately 300 K.According to the LKT/BCT model,the calculated results of the primary β-Zr dendrite growth velocity in undercooled liquid Zr_(91.4)V_(8.6) and Zr_(83.5)V_(16.5) alloys agree well with the experiments.The velocity inflection points at 119 K of Zr_(91.4)V_(8.6) alloy and 201 K of Zr_(83.5)V_(16.5) alloy could be explained by the competition between solutal undercooling control and thermal undercooling control modes.For Zr_(70)V_(30) alloy solidified in the P1 with twice recalescence,a critical second undercooling of 253 K and corresponding undercooling of 65 and 244 K are obtained.When the un-dercooling is in the range of 65-244 K,the second undercooling would be greater than 253 K,and the residual liquid phase would solidify into anomalous eutectic microstructure for Zr_(70)V_(30) alloy.The Vickers hardness of Zr_(100-x)V_(x)(x=8.6,16.5,30)alloys all show a quadratic relationship with undercooling.Under electrostatic levitation condition,the mechanical property of Zr-V alloys could be significantly regulated through solidifying the alloys at different undercoolings.展开更多
Electrostatic ion-cyclotron wave(EICW)and ion-Bernstein wave(IBW)are two typical normal modes of plasma propagating vertically to a magnetic field.These modes satisfy the extreme conditionsω《k_(||)v_(te)andω》k_(||...Electrostatic ion-cyclotron wave(EICW)and ion-Bernstein wave(IBW)are two typical normal modes of plasma propagating vertically to a magnetic field.These modes satisfy the extreme conditionsω《k_(||)v_(te)andω》k_(||)v_(te),whereω,k_(||),and v_(te)are the wave angular frequency,wave number parallel to the magnetic field,and the electron thermal speed.Between these extremities,there exist IBW-like waves that have not been studied.In this paper,the co-excitation of the EICW and IBW-like wave in an experiment is presented.It is shown that,in an argon(Ar)discharge,the EICW appears in the fundamental and second harmonic frequency bands of the ioncyclotron frequency.In contrast,the IBW-like wave appears in the higher harmonic frequency bands and in the case of a relatively strong magnetic field.In a helium(He)discharge,the IBW-like wave is excited in the fundamental frequency band,but the wave behaviour becomes complicated in the harmonic frequency bands.The measured dispersion relations of the excited EICW are in agreement with the results of the fluid and kinetic models in some range of frequencies,but those of the excited IBW-like wave are only in qualitative agreement with the kinetic model of the IBW.This study is important for identifying the IBW-like mode that may have potential application in plasma heating via Landau damping.展开更多
The potential of metal nanoclusters in biomedical applications is limited due to aggregation-caused quenching(ACQ).In this study,an in situ self-assembled pitaya structure was proposed to obtain stable fluorescence em...The potential of metal nanoclusters in biomedical applications is limited due to aggregation-caused quenching(ACQ).In this study,an in situ self-assembled pitaya structure was proposed to obtain stable fluorescence emission through protein coronas-controlled distance between gold nanoclusters(Au NCs).Interestingly,the gold ion complexes coated with proteins of low isoelectric point(pI)nucleate at the secondary structure of proteins with high p I through ionic exchange within cells,generating fluorescent Au NCs.It is worth noting that due to the steric hindrance formed by the protein coronas on the surface of Au NCs,the distance between Au NCs can be controlled,avoiding electron transfer caused by close proximity of Au NCs and inhibiting fluorescence ACQ.This strategy can achieve fluorescence imaging of clinical tissue samples without observable side effects.Therefore,this study proposes a distance-controllable self-assembled pitaya structure to provide a new approach for Au NCs with stable fluorescence.展开更多
The development of new and efficient extractants plays a key role in the separation and recovery of rare earth elements.In this pape r,the extractant(N,N-methyl py ridineethyl-N',N'-dicyclohexyl-3-oxadiglycola...The development of new and efficient extractants plays a key role in the separation and recovery of rare earth elements.In this pape r,the extractant(N,N-methyl py ridineethyl-N',N'-dicyclohexyl-3-oxadiglycolamide,MPyEDChDGA) with a new structure was synthesized,and the pyridine group was successfully grafted onto the 3-oxadiglycolamide structure.Using MPyEDChDGA for efficient enrichment of rare earth ions,the self-assembled solids were recovered by simple filtration without further backextraction and final precipitation,achieving a one-step strategy for the recovery of rare earth ions.Several important parameters affecting the self-assembly extraction,including pH,diluent,temperature,and extractant concentration,were systematically evaluated using La(NO_(3))_(3),Tb(NO_(3))_(3),and Lu(NO_(3))_(3) as representatives.The self-assembled solids were investigated in detail by X-ray diffraction(XRD),scanning electron microscopy(SEM),1H nuclear magnetic resonance(1H NMR),Fourier transform infrared spectroscopy(FT-IR),Raman,and X-ray photoelectron spectroscopy(XPS) analyses.The stoichiometry of the extraction species was characterized using the Job's method and electrospray ionization mass spectrometry(ESI-MS).In addition,MPyEDChDGA was applied to the recovery of Sm in SmCoCu simulated liquid,and the results show that MPyEDChDGA has good selectivity of Sm from transition metals(Co,Cu).The separation factor of Sm/Co can reach 6281±117,which provides a new approach to recovering Sm from SmCoCu scrap magnets.This study presents an efficient and convenient new strategy for the recovery and separation of rare earth elements.展开更多
A theoretical study of the influence of a quasi-electrostatic support on the amplification level of the slow space charge wave(SCW) in the amplification section of a superheterodyne free electron laser(FEL) was carrie...A theoretical study of the influence of a quasi-electrostatic support on the amplification level of the slow space charge wave(SCW) in the amplification section of a superheterodyne free electron laser(FEL) was carried out. One of the ways to significantly increase the saturation level of the slow SCW is maintaining the conditions of a three-wave parametric resonance between the slow, fast SCWs and the resulting pump electric field. This can be done by introducing the quasielectrostatic support in the superheterodyne FEL amplification section. Also, it was found that the generated pump electric field significantly influences the maintenance of parametric resonance conditions. As a result, this increases the saturation level of the slow SCW by 70%. Finally, the quasi-electrostatic support significantly reduces the maximum value of the electrostatic undulator pump field strength, which is necessary to achieve the maximum saturation level of the slow SCW.展开更多
Amphiphilic asymmetric brush copolymers(AABCs)possess unique self-assembly behaviors owing to their asymmetric brush architecture and multiple functionalities of multicomponent side chains.However,the synthesis of AAB...Amphiphilic asymmetric brush copolymers(AABCs)possess unique self-assembly behaviors owing to their asymmetric brush architecture and multiple functionalities of multicomponent side chains.However,the synthesis of AABCs presents challenges,which greatly limits the exploration of their self-assembly behaviors.In this work,we employed dissipative particle dynamics(DPD)simulations to investigate the self-assembly behaviors of AABCs in selective solution.By varying the copolymer concentration and structure,we conducted the self-assembly phase diagrams of AABCs,revealing complex morphologies such as channelized micelles with one or more solvophilic channels.Moreover,the number,surface area,and one-dimensional density distribution of the channelized micelles were calculated to demonstrate the internal structure and morphological transformation during the self-assembly process.Our findings indicate that the morphology of the internal solvophilic channels is greatly influenced by the copolymer structure,concentration,and interaction parameters between the different side chains.The simulation results are consistent with available experimental observations,which can offer theoretical insights into the self-assembly of AABCs.展开更多
基金supported by the National Natural Science Foundation of China(No.51972198)Shandong Provincial Science and Technology Key Project(No.2018GGX104002)+7 种基金Taishan Scholars Program of Shandong Province(No.tsqn201812002)Independent Innovation Foundation of Shandong Universitythe State Key Program of National Natural Science of China(Nos.61633015,51532005)the Young Scholars Program of Shandong University(No.2016WLJH03),the Project of the Taishan Scholar(No.ts201511004)Shandong Provincial Natural Science Foundation(No.ZR2017MB001)Discipline Construction of High-Level Talents of Shandong University(No.31370089963078)1000 Talent Plan program(No.31370086963030)the National Natural Science Foundation of China(No.21371108)。
文摘Available onlineSilicon monoxide(SiO)is a promising anode material fo r lithium-ion batteries(LIBs)due to its high theoretical specific capacity(~2400 mAh/g),low working potential(<0.5 V vs.Li^+/Li),low cost,easy synthesis,nontoxicity,abundant natural source and smaller volume expansion than Si.However,low intrinsic electrical conductivity,low initial Coulombic efficiency(ICE)and inevitable volume expansion(~200%)impede its practical application.Here we fabricate SiO/wrinkled MXene composite(SiO-WM)by an electrostatic self-assembly method.Importantly,this method is simple,scalable and taking into account all the issues of SiO.As a result,the SiO-WM exhibits imp roved rate capability,cycling performance and ICE than bare SiO.
基金financially supported by the Fundamental Research Funds for the Central Universities (No. 2019XKQYMS16)
文摘Constructing electrode materials with large capacity and good conductivity is an effective approach to improve the capacitor performance of asymmetric supercapacitors(ASCs).In this paper,ZnCo_(2)S_(4)core-shell nanospheres are constructed by two-step hydrothermal method.In order to improve the chemical activity of ZnCo_(2)S_(4),ZnCo_(2)S_(4)is activated using cetyltrimethylammonium bromide(CTAB).Then,MXene nanosheets are fixed on the surface of ZnCo_(2)S_(4)by electrostatic selfassembly method to improve the specific surface area of ZnCo_(2)S_(4)and MXene-wrapped ZnCo_(2)S_(4)composite is prepared in this work.Owing to the synergy effect between MXene nanosheets and ZnCo_(2)S_(4)core-shell nanospheres,the as-prepared composite displays fast ion transfer rate and charge/discharge process.The capacity of the MXenewrapped ZnCo_(2)S_(4)composite can reach 1072 F·g^(-1),which is far larger than that of ZnCo_(2)S_(4)(407 F·g^(-1))at 1 A·g^(-1).An ASC device is assembled,which delivers 1.7 V potential window and superior cyclic stability(95.41%capacitance retention).Furthermore,energy density of this device is up to 30.46 Wh·kg^(-1)at a power density of850 W·kg^(-1).The above results demonstrate that MXenewrapped ZnCo_(2)S_(4)composite has great application prospects in electrochemical energy storage field.
基金Funded by the Natural Science Foundation of Hebei Province, China (No. E2008000537)the Foundation for Development of Science and Technology of Hebei Province, China (No. 07215156)the Open Research Foundation of Key Laboratory of Advanced Civil Engineering Materials (Tongji University),Ministry of Education, China (No. 2010412)
文摘Electrostatic self-assembly method （ESAM） was used to prepare bentonite supported-nano titanium dioxide photocatalysts. The materials were characterized by X-ray diffraction （XRD）, fourier transform infrared spectroscopy （FT-IR） and scanning electron microscopy （SEM）. Methyl orange was used to estimate the photocatalytic activity of the materials. The effects of the calcination temperature and silane dosage on the photocatalytic activity of the samples were investigated. The experimental results show that the bentonite facilitates the formation of anatase and restrains the transformation of anatase to rutile. Part of nano-size TiO2 particles insert into the galleries of bentonite. The photocatalysts exhibit a synergistic effect of adsorption and photocatalysis on methyl orange. Photocatalysts prepared by ESAM method exhibit higher photocatalytic activity and better recycle ability than those of the traditional method.
文摘Anionic surfactant sodium lauryl sulfate(SDS), cationic surfactant palmityl trimethyl ammonium chloride(CTAC) and TiO_2 were used to prepare multilayer films on quartz optic fibers by the electrostatic self-assembly (ESA) method. The whole self-assemble process, the function of surfactant and the effect of TiO_2 slurry′s concentration to the self-assemble were discussed. The isoelectric point of TiO_2 slurry measured by experiment is 6.8. The results show that whatever the concentration of the TiO_2 dispersion, a flat and compact adsorbed monolayer on the optic fiber can be built in a stable dispersion at lower pH. There is a adsorbed equilibrium on the substrate (fiber)/solution interface when enough time of incubation is given. A rough and loosen adsorbed layer is formed on the fiber surface by immersed the substrate in a high pH dispersion (pH>10) because the presence of hydroxyl on particle surface. Film thickness can be controlled by controlling the number of layers in the film.
基金This research was financially supported by China Scholar-ship Council and the Natural Science Foundation of Hubei Province (Project 2000J002)
文摘Gold colloids were prepared by citrate-induced reduction of hydrogen tetrachloroaurale, and gold nanoparticles were electrostatically self-assembled with poly( diallyldimethylammonium chloride) into multi-layer thin films on si/icon and quartz substrates. The paniculate thin films were characterized by UV-vis spea-troscopy, surface, enhanced Raman scattering, atomic force microscopy and resistivity measurements. Due to the interparticle coupling between individual gold particles, an obvious collective particle plasmon resonance was ob-served on UV-vis spectra , and the particulate thin films exhibited a strong SERS effect. For multilayer thin films with a high particle coverage on substrates , resistivity of the order of 10-4 Ω·cm was yielded.
基金supported by the National Nature Science Foundation of China(No.51562006)Guangxi Distinguished Experts Special Fund(No.2019B06)Innovation Project of Guangxi Graduate Education(No.SC2200000985).
文摘Aqueous zinc ion batteries have become highly favored energy storage devices owing to low cost and environmental friendliness.Vanadium oxide,as one of the potential cathodes for AZIBs,is plagued by several unfavorable elements including unsatisfactory conductivity and vanadium dissolution in the electrolyte.Herein,an electrostatic self-assembly strategy is proposed to introduce conductive dielectric Ti_(3)C_(2)T_(x)MXene nanoplates into V_(2)O_(5)·4VO_(2)nanoribbons,where V_(2)O_(5)·4VO_(2)/MXene composites(denoted as VM2)are simply obtained by magnetic stirring combined with ultrasonic method at room temperature.The successful introduction of MXene with high electrical conductivity not only endows faster V_(2)O_(5)·4VO_(2)electron/ion transfer,but also acts as a"baffle"to inhibit vanadium dissolution.Benefiting from the above advantages,paired with a zinc metal anode,VM2 cathode exhibits impressive performance metrics of 328.7 mAh·g^(−1)at 0.1 A·g^(−1),95.8%capacity retention after 1000 cycles,and 142.9 mAh·g^(−1)at a current density of 20 A·g^(−1).This work provides a viable reference for the development of high-performance AZIBs.
基金The authors gratefully acknowledge the support for this work from the National Key research and Development Program(Grant No.2018YFA0703100)the National Natural Science Foundation of China(Grant Nos.82072082,31900959)+2 种基金the Youth Innovation Promotion Association of CAS(Grant No.2019350)the Guangdong Natural Science Foundation(Grant No.2019A1515011277)the Shenzhen Fundamental Research Foundation(Grant No.JCYJ20180507182237428).
文摘Low patency ratio of small-diameter vascular grafts remains a major challenge due to the occurrence of thrombosis formation and intimal hyperplasia after transplantation.Although developing the functional coating with release of bioactive molecules on the surface of small-diameter vascular grafts are reported as an effective strategy to improve their patency ratios,it is still difficult for current functional coatings cooperating with spatiotemporal control of bioactive molecules release to mimic the sequential requirements for antithrombogenicity and endothelialization.Herein,on basis of 3D-printed polyelectrolyte-based vascular grafts,a biologically inspired release system with sequential release in spatiotemporal coordination of dual molecules through an electrostatic self-assembly was first described.A series of tubes with tunable diameters were initially fabricated by a coaxial extrusion printing method with customized nozzles,in which a polyelectrolyte ink containing of ε-polylysine and sodium alginate was used.Further,dual bioactive molecules,heparin with negative charges and Tyr-Ile-Gly-Ser-Arg(YIGSR)peptide with positive charges were layer-by-layer assembled onto the surface of these 3D-printed tubes.Due to the electrostatic interaction,the sequential release of heparin and YIGSR was demonstrated and could construct a dynamic microenvironment that was thus conducive to the antithrombogenicity and endothelialization.This study opens a new avenue to fabricate a small-diameter vascular graft with a biologically inspired release system based on electrostatic interaction,revealing a huge potential for development of small-diameter artificial vascular grafts with good patency.
基金National Key Research and Development Program of China(2017YFB0903804)Science and Technology Program of the State Grid Corporation of China(No.5455DW170026).
文摘High-performance epoxy(EP)composites with excellent thermal conductivity and dielectric properties have attracted increasing attention for effective thermal management.In this work,three-dimensional(3D)structural functional fillers were prepared by an electrostatic self-assembly approach.The negatively charged carbon nanotubes(nCNTs)prepared by carboxylation on the surface of CNTs were attached to the positively charged boron nitride(pBN)to form the 3D pBN@nCNTs functional fillers.The morphological characterizations of the formed 3D pBN@nCNTs fillers and epoxy composites were established,illustrating that nCNTs were linearly overlapped between the BN sheets,thus forming a 3D heat conduction network in the epoxy matrix.The synergistic effect of pBN with nCNTs on the enhancement of thermal conductivity and dielectric properties of composites was systematically studied.The experimental results demonstrated that the thermal conductivity of pBN@nCNTs/EP composites could reach 1.986 W m1K1 with the loading of 50 wt%fillers at 10:1 mass ratio of pBN:nCNTs,which is 464%and 124%higher than that of pure EP and BN/EP,respectively.Simultaneously,the dielectric permittivity was successfully increased to 15.14.Moreover,the thermal stability of the composites was synchronously enhanced.This study provides a facile path to fabricate thermosetting polymer composites with high thermal conductivity and dielectric properties.
基金supported by the National Research Foundation of Korea(NRF)grant funded by the Korean government(MSIT)(No.2020R1C1C1003375)。
文摘Recently,hollow carbon nanospheres(HCSs)have garnered significant attention as potential Li metal hosts owing to their unique large voids and ease of fabrication.However,similar to other nanoscale hosts,their practical performance is limited by inhomogeneous agglomeration,increased binder requirements,and high tortuosity within the electrode.To overcome these problems and high tortuosity within the electrode,this study introduces a pomegranate-like carbon microcluster composed of primary HCSs(P-CMs)as a novel Li metal host.This unique nanostructure can be easily prepared using the spray-drying technique,enabling its mass production.Comprehensive analyses with various tools demonstrate that compared with HCS hosts,the P-CM host requires a smaller amount of binder to fabricate a sufficiently robust and even surface electrode.Furthermore,owing to reduced tortuosity,the well-designed P-CM electrode can provide continuous and shortened pathways for electron/ion transport,accelerating the Li-ion transfer kinetics and prohibiting preferential Li plating at the upper region of the electrode.Due to these characteristics,Li metal can be effectively encapsulated in the large inner voids of the primary HCSs constituting the P-CM,thereby enhancing the electrochemical performance of P-CM hosts in Li metal batteries.Specifically,the Coulombic efficiency of the P-CM host can be maintained at 97%over 100 cycles,with a high Li deposition areal capacity of 3 mAh·cm^(-2)and long cycle life(1000 h,1 mA·cm^(-2),and 1.0 mAh·cm^(-2)).Furthermore,a full cell incorporating a LiFePO4 cathode exhibits excellent cycle life.
文摘Four glycoluril-based amphiphilic molecular clips(AMCs)M1~M4 have been prepared for intracellular delivery of short DNA.M1~M4 have two methyl groups on its convex surface and four cations on its aromatic side arm,which can be used to construct self-assembled nanoparticles in aqueous solution driven by hydrophobic interaction.Dynamic light scattering experiments show that M1 and M2 can be driven hydrophobically to aggregate into extremely stable nanoparticles in water at the micromolar concentrations.Fluorescence titration and zeta potential experiments support that the nanoparticles formed by M1 and M2 are able to efficiently encapsulate short DNA(sDNA).Fluorescence imaging and flow cytometry studies reveal that their nano sizes enable intracellular delivery of the encapsulated sDNA into both normal and cancer cells,with delivery percentage reaching up to 94%,while in vitro experiments indicate that the two compounds have excellent biocompatibility and low cytotoxicity.
基金National Natural Science Foundation of China(No.22275150)。
文摘To study the influence of silicon(Si)on 2,4,6,8,10,12-hexanitro-2,4,6,8,10,12-hexaazaisowurtzitane(CL-20),NC/CL-20 composite explosives and Si/NC/CL-20 composite explosives were prepared by the electrostatic spraying method.The morphology,structure and thermal decomposition properties of the samples were analyzed using scanning electron microscopy(SEM),X-ray energy spectroscopy(EDS),infrared spectroscopy(FT-IR),and simultaneous thermal analyzer(TG-DSC).Additionally,the combustion process of the samples was tested using a high-speed camera.The results show that the addition of nano-Si contributes to the formation of composite explosives with regular morphology and smaller particle size.The Si/NC/CL-20 composite explosive has better and more uniform sphericity,with an average particle size of 73.4 nm,compared to the NC/CL-20 composite explosive.The Si/NC/CL-20 composite explosive which produced by the electrostatic spraying method,achieves physically uniform distribution of the components including NC,CL-20,Si.The addition of Si promotes the thermal decomposition of CL-20.In comparison to the NC/CL-20 composite explosive,the activation energy of the Si/NC/CL-20 composite explosive decreases by 16.78 kJ/mol,and the self-accelerated decomposition temperature and the critical temperature of thermal explosion decreases by 3.12 K and 2.61 K,respectively.Furthermore,Si/NC/CL-20 composite explosive has shorter ignition delay time and faster combustion rate compared to the NC/CL-20 composite explosive,which shows that Si can improve the combustion performance of CL-20.
基金The National Natural Science Foundation of China(No.51976039)。
文摘To explore the electrostatic discharge behavior of charged powders in industrial silos,discharge experiments are conducted based on a full-size industrial silo discharge platform.Electrostatic discharge mode,frequency,and energy are investigated for powders of different polarities.Although the powders have low charge-to-mass ratios(+0.087μC/kg for the positively charged powders and−0.26μC/kg for the negatively charged ones),electrostatic discharges occur approximately every 10 s,with the maximum discharge energy being 800 mJ.Powder polarity considerably influences discharge energy.The positive powders exhibit higher discharge energy than the negative ones,although discharge frequency remains similar for both.Effects of powder charge,humidity,and mass flow on discharge frequency and discharge energy are quantitatively analyzed,providing important insights for the improvement of safety in industrial powder handling.
基金supported by the National Natural Science Foundation of China(No.62075069 and 52303092)the Water Conservancy Technology project of Hunan Province,China(XSKJ2021000-32)+1 种基金the City University of Hong Kong(#7005507)the Open Project of Yunnan Precious Metals Laboratory Co.,Ltd(grant number YPML-2023050278).
文摘Nowadays,high-stable and ultrasensitive heavy metal detection is of utmost importance in water quality monitoring.Nanoparticle-enhanced laser-induced breakdown spectroscopy(NELIBS)shows high potential in hazardous metal detection,however,encounters unstable and weak signals due to nonuniform distribution of analytes.Herein,we developed an interface self-assembly(ISA)method to create a uniformly distributed gold nanolayer at a liquid-liquid interface for positive heavy metal ions capture and NELIBS analysis.The electrostatically selfassembled Au nanoparticles(NPs)-analytes membrane was prepared at the oil-water interface by injecting ethanol into the mixture of cyclohexane and Au NPs-analytes water solution.Then,the interface self-assembled Au NPs-analytes membrane was transformed onto a laser-processed superhydrophilic Si slide for detection.Three heavy metals(cadmium(Cd),barium(Ba),and chromium(Cr))were analyzed to evaluate the stability and sensitivity of the ISA method for NELIBS.The results(Cd:RSD=3.6%,LoD=0.654 mg/L;Ba:RSD=3.4%,LoD=0.236 mg/L;Cr:RSD=7.7%,LoD=1.367 mg/L)demonstrated signal enhancement and high-stable and ultrasensitive detection.The actual sample detection(Cd:RE=7.71%,Ba:RE=6.78%)illustrated great reliability.The ISA method,creating a uniform distribution of NP-analytes at the interface,has promising prospects in NELIBS.
基金financially supported by the National Natural Science Foundation of China(Nos.20904047 and 12074151)the Natural Science Foundation of Zhejiang Province(Nos.LY17A040001 and LY19F03004)。
文摘Diphenylalanine and its analogs cause many concerns owing to their perfect self-assembly properties in the fields of biology,medicine,and nanotechnology.Experimental research has shown that diphenylalanine-based analogs with ethylenediamine linkers(PA,P=phenylalanine,and A=analog)can self-assemble into spherical assemblies,which can serve as novel anticancer drug carriers.In this work,to understand the assembly pathways,drug loading behavior,and formation mechanism of PA aggregates at the molecular level,we carried out dissipative particle dynamics(DPD)simulations of PA molecule systems.Our simulation results demonstrate that PA molecules spontaneously assemble into nanospheres and can self-assemble into drug-loaded nanospheres upon addition of the cancer chemotherapeutic agent doxorubicin(DOX).We also found that the hydrophobic side chain beads of PA molecules exhibited a unique onion-like distribution inside the nanospheres,which was not observed in the experiment.The onion-like nanospheres were verified by calculating the radial distribution function(RDF)of the DPD beads.Furthermore,based on the analysis of the percentages of different interaction components in the total nonbonded energies,main chain-side chain interactions between PA molecules may be important in the formation of onion-like nanospheres,and the synergistic effects of main chain-side chain,main chain-drug,side chain-drug,and main chain-solvent interactions are significant in the formation of drug-loaded nanospheres.These findings provide new insights into the structure and self-assembly pathway of PA assemblies,which may be helpful for the design of efficient and effective drug delivery systems.
基金supported by the National Natural Science Foundation of China(Grant No.52088101)the Space Utilization System of China Manned Space Engineering(Grant No.KJZ-YY-NCL02)+1 种基金the National Key R&D Program of China(Grant No.2021YFA0716301)the Shannxi Key Science and Technology Program(Grant Nos.2023-ZDLGY-36,2024JC-ZDXM-24).
文摘The liquid Zr_(100-x)V_(x)(x=8.6,16.5,30)alloys were undercooled to the maximum undercooling of 364 K(0.18 T_(L)),405 K(0.21 T_(L)),and 375 K(0.21 T_(L)),respectively,by using electrostatic levitation technique.The Zr_(91.4)V_(8.6) and Zr_(83.5)V_(16.5) alloys present only one recalescence during liquid/solid phase transition,while the Zr_(70)V_(30) alloy presents a transformation from two recalescence to one recalescence phenomenon with a critical undercooling of approximately 300 K.According to the LKT/BCT model,the calculated results of the primary β-Zr dendrite growth velocity in undercooled liquid Zr_(91.4)V_(8.6) and Zr_(83.5)V_(16.5) alloys agree well with the experiments.The velocity inflection points at 119 K of Zr_(91.4)V_(8.6) alloy and 201 K of Zr_(83.5)V_(16.5) alloy could be explained by the competition between solutal undercooling control and thermal undercooling control modes.For Zr_(70)V_(30) alloy solidified in the P1 with twice recalescence,a critical second undercooling of 253 K and corresponding undercooling of 65 and 244 K are obtained.When the un-dercooling is in the range of 65-244 K,the second undercooling would be greater than 253 K,and the residual liquid phase would solidify into anomalous eutectic microstructure for Zr_(70)V_(30) alloy.The Vickers hardness of Zr_(100-x)V_(x)(x=8.6,16.5,30)alloys all show a quadratic relationship with undercooling.Under electrostatic levitation condition,the mechanical property of Zr-V alloys could be significantly regulated through solidifying the alloys at different undercoolings.
基金supported by National Natural Science Foundation of China (No.11975229)。
文摘Electrostatic ion-cyclotron wave(EICW)and ion-Bernstein wave(IBW)are two typical normal modes of plasma propagating vertically to a magnetic field.These modes satisfy the extreme conditionsω《k_(||)v_(te)andω》k_(||)v_(te),whereω,k_(||),and v_(te)are the wave angular frequency,wave number parallel to the magnetic field,and the electron thermal speed.Between these extremities,there exist IBW-like waves that have not been studied.In this paper,the co-excitation of the EICW and IBW-like wave in an experiment is presented.It is shown that,in an argon(Ar)discharge,the EICW appears in the fundamental and second harmonic frequency bands of the ioncyclotron frequency.In contrast,the IBW-like wave appears in the higher harmonic frequency bands and in the case of a relatively strong magnetic field.In a helium(He)discharge,the IBW-like wave is excited in the fundamental frequency band,but the wave behaviour becomes complicated in the harmonic frequency bands.The measured dispersion relations of the excited EICW are in agreement with the results of the fluid and kinetic models in some range of frequencies,but those of the excited IBW-like wave are only in qualitative agreement with the kinetic model of the IBW.This study is important for identifying the IBW-like mode that may have potential application in plasma heating via Landau damping.
基金supported by the National Natural Science Foundation of China(Nos.82061148012,82027806,21974019)SEU Innovation Capability Enhancement Plan for Doctoral Students(No.CXJH_SEU 24138)Postgraduate Research&Practice Innovation Program of Jiangsu Province(No.KYCX24_0469)。
文摘The potential of metal nanoclusters in biomedical applications is limited due to aggregation-caused quenching(ACQ).In this study,an in situ self-assembled pitaya structure was proposed to obtain stable fluorescence emission through protein coronas-controlled distance between gold nanoclusters(Au NCs).Interestingly,the gold ion complexes coated with proteins of low isoelectric point(pI)nucleate at the secondary structure of proteins with high p I through ionic exchange within cells,generating fluorescent Au NCs.It is worth noting that due to the steric hindrance formed by the protein coronas on the surface of Au NCs,the distance between Au NCs can be controlled,avoiding electron transfer caused by close proximity of Au NCs and inhibiting fluorescence ACQ.This strategy can achieve fluorescence imaging of clinical tissue samples without observable side effects.Therefore,this study proposes a distance-controllable self-assembled pitaya structure to provide a new approach for Au NCs with stable fluorescence.
基金Project supported by the Natural Science Foundation of Shandong Province (ZR2022QB067)。
文摘The development of new and efficient extractants plays a key role in the separation and recovery of rare earth elements.In this pape r,the extractant(N,N-methyl py ridineethyl-N',N'-dicyclohexyl-3-oxadiglycolamide,MPyEDChDGA) with a new structure was synthesized,and the pyridine group was successfully grafted onto the 3-oxadiglycolamide structure.Using MPyEDChDGA for efficient enrichment of rare earth ions,the self-assembled solids were recovered by simple filtration without further backextraction and final precipitation,achieving a one-step strategy for the recovery of rare earth ions.Several important parameters affecting the self-assembly extraction,including pH,diluent,temperature,and extractant concentration,were systematically evaluated using La(NO_(3))_(3),Tb(NO_(3))_(3),and Lu(NO_(3))_(3) as representatives.The self-assembled solids were investigated in detail by X-ray diffraction(XRD),scanning electron microscopy(SEM),1H nuclear magnetic resonance(1H NMR),Fourier transform infrared spectroscopy(FT-IR),Raman,and X-ray photoelectron spectroscopy(XPS) analyses.The stoichiometry of the extraction species was characterized using the Job's method and electrospray ionization mass spectrometry(ESI-MS).In addition,MPyEDChDGA was applied to the recovery of Sm in SmCoCu simulated liquid,and the results show that MPyEDChDGA has good selectivity of Sm from transition metals(Co,Cu).The separation factor of Sm/Co can reach 6281±117,which provides a new approach to recovering Sm from SmCoCu scrap magnets.This study presents an efficient and convenient new strategy for the recovery and separation of rare earth elements.
文摘A theoretical study of the influence of a quasi-electrostatic support on the amplification level of the slow space charge wave(SCW) in the amplification section of a superheterodyne free electron laser(FEL) was carried out. One of the ways to significantly increase the saturation level of the slow SCW is maintaining the conditions of a three-wave parametric resonance between the slow, fast SCWs and the resulting pump electric field. This can be done by introducing the quasielectrostatic support in the superheterodyne FEL amplification section. Also, it was found that the generated pump electric field significantly influences the maintenance of parametric resonance conditions. As a result, this increases the saturation level of the slow SCW by 70%. Finally, the quasi-electrostatic support significantly reduces the maximum value of the electrostatic undulator pump field strength, which is necessary to achieve the maximum saturation level of the slow SCW.
基金supported by the National Science Foundation for Distinguished Young Scholars(No.52325308)the National Natural Science Foundation of China(Nos.52273008 and 52073092)+1 种基金Shanghai Scientific and Technological Innovation Projects(No.22ZR1479300)Shanghai Rising-Star Program(No.23QA1402500).
文摘Amphiphilic asymmetric brush copolymers(AABCs)possess unique self-assembly behaviors owing to their asymmetric brush architecture and multiple functionalities of multicomponent side chains.However,the synthesis of AABCs presents challenges,which greatly limits the exploration of their self-assembly behaviors.In this work,we employed dissipative particle dynamics(DPD)simulations to investigate the self-assembly behaviors of AABCs in selective solution.By varying the copolymer concentration and structure,we conducted the self-assembly phase diagrams of AABCs,revealing complex morphologies such as channelized micelles with one or more solvophilic channels.Moreover,the number,surface area,and one-dimensional density distribution of the channelized micelles were calculated to demonstrate the internal structure and morphological transformation during the self-assembly process.Our findings indicate that the morphology of the internal solvophilic channels is greatly influenced by the copolymer structure,concentration,and interaction parameters between the different side chains.The simulation results are consistent with available experimental observations,which can offer theoretical insights into the self-assembly of AABCs.
