To deal with the growing electromagnetic hazards,herein a Co@CuFe_(2)O_(4)absorbing agent with excellent impedance matching at thin thickness was obtained via an innovative route of ball-milling assisted chemical prec...To deal with the growing electromagnetic hazards,herein a Co@CuFe_(2)O_(4)absorbing agent with excellent impedance matching at thin thickness was obtained via an innovative route of ball-milling assisted chemical precipitation and annealing.The as-prepared composite possesses excellent interface polarization ability due to sufficient contact between CuFe_(2)O_(4)NPs and flat Co,and this compressed Co lamella can also provide sufficient eddy current loss.Moreover,the dipole polarization,electron hopping/conduction,and structural scattering also contribute to the broadband microwave absorption of the composite.Thus,the minimum microwave reflection loss achieves-35.56 d B at12.93 GHz for 1.8 mm thickness,and the broadest efficient absorption bandwidth can reach 6.74 GHz for a thinner thickness of 1.72 mm.The preparation method reported here can be referenced as a new-type route to manufacture electromagnetic absorbers with outstanding performance.展开更多
The Ni-Al2O3 catalyst was prepared by the mechanochemical method in combination with a planetary ballmilling machine.Effect of milling time on the crystal structure,the reduction characteristics and the catalytic perf...The Ni-Al2O3 catalyst was prepared by the mechanochemical method in combination with a planetary ballmilling machine.Effect of milling time on the crystal structure,the reduction characteristics and the catalytic performance of Ni-Al2O3 catalyst for hydrogenation of 1,4-butynediol to produce 1,4-butenediol were investigated.The catalysts were characterized by PSD,EDX,XRD,H2-TPR,BET,TEM,and NH3-TPD methods.Results showed that the MCt2.5 catalyst treated at a ball milling time of 2.5 h could form a smallest particle size of 191.0 nm.The evaluation experiments revealed that the activity of the prepared catalyst increased at first and then reached a constant value with the extension of ballmilling time.The BYD conversion,BED selectivity and yield on the MCt2.5 catalyst reached 35.63%,33.48%and 32.46%,respectively,which were higher than those obtained by other samples.The excellent performance of MCt2.5 sample is mainly related to the following three reasons from characterization results.Firstly,it has a smallest particle size of 191.0 nm;and then,the surface acidity(in terms of strong acids)of the catalyst was weaker than other catalysts;and eventually,the loading amount(23.84%)of the active component Ni exceeded the theoretical value(20%).展开更多
Cellulose is a linear polymer consisting of D-anhydroglucose units joined by β-1,4-glycosidic linkages. The densely packed cellulose molecular chain forms crystalline cellulose through strong hydrogen bonding. Owing ...Cellulose is a linear polymer consisting of D-anhydroglucose units joined by β-1,4-glycosidic linkages. The densely packed cellulose molecular chain forms crystalline cellulose through strong hydrogen bonding. Owing to its chemical tunability and excellent mechanical resistance, nanocellulose is widely used in everyday life and the industrial sector. In this work, cellulose materials were nanoprocessed by mechanical ball-milling(1) in polar solvents(N,N-dimethylformamide or dimethyl sulfoxide) with esterification or(2) in hydrophobic agents(polydimethylsiloxane or polytetrafluoroethylene) with different molecular weights. Cellulose nanofibers and nanosheets with different hydrophilic and hydrophobic properties were obtained, and the mechanism of cellulose disintegration along a crystallographic plane induced by mechanical force and the polarity condition were discussed. This work affords a new way to manipulate the morphology and properties of nanocellulose.展开更多
Manganese (Mn) is an essential element for human body. However, elevated concentration of manganese causes severe problem and disease. Acid mine drainage (AMD), wastewater generated due to open-pit mining, commonly co...Manganese (Mn) is an essential element for human body. However, elevated concentration of manganese causes severe problem and disease. Acid mine drainage (AMD), wastewater generated due to open-pit mining, commonly contains Mn with exceeded concentration. This study is to investigate the improvement of ball-milling modified Indonesian natural bentonite (INB) for manganese (Mn) removal from AMD and to increase the pH through batch and column sorption test as a passive treatment system approach. The batch sorption test result showed the maximum Mn adsorbed (Qm) on INB from the Langmuir model increased from 4.69 to 17.12 mg/g after milling. The column sorption test result also showed the amount of Mn adsorbed on INB until breakthrough time (qu) and until saturation time (q) increased after milling. The qu increased from 1.27 to 10.06 mg/g, and the q increased from 4.55 to 12.91 mg/g. The mass transfer zone (MTZ) became significantly shorter after milling from 0.22 to 0.07 cm. The Thomas model exhibited the equilibrium uptake of Mn (q0) increased after milling from 3.91 to 13.72 mg/g. In equilibrium condition, both unmilled and milled INB showed the pH increased from ≈3 to 8.展开更多
Water-soluble lignin-carbohydrate complex(LCC)rich in polysaccharides exhibits benign in vitro antioxidant activities and distinguishes high biocompatibility from lignin-rich LCC and lignin.However,the antioxidant act...Water-soluble lignin-carbohydrate complex(LCC)rich in polysaccharides exhibits benign in vitro antioxidant activities and distinguishes high biocompatibility from lignin-rich LCC and lignin.However,the antioxidant activity of water-soluble LCCs remains to be improved and its structure-antioxidant relationship is still uncertain.Herein,structurally diversified water-soluble LCCs were isolated under different ball-milling pretreatment durations(4,6,8 h),extraction pathways(ho-mogeneous and heterogeneous),and isolation routines(water extracts and residues after water extraction).Their structures were characterized by wet chemistry,chromatography and spec-troscopies.Antioxidant activities were evaluated by ferric reducing antioxidant power and 1,1-diphenyl-2-picrylhydrazyl radicals scavenging rate(RDPPH).Results show that altering ball-milling duration and isolation procedures cause varied structures and antioxidant activities of the water-soluble LCCs.Specifically,prolonging ball-milling duration to 8 hours and homogeneous extrac-tion can enhance their antioxidant activity through releasing more phenolic structures and pro-moting the extraction of high-molecular-weight LCCs via reducing mass-transfer resistance,re-spectively.As a result,the RDPPH of water-soluble LCCs reaches up to 97.35%,which is associated with the arabinan content with statistical significance(P<0.05).This study provides new insights into the structure-antioxidation relationship of herbaceous LCC as potential antioxidants.展开更多
We reported an economic and practical ball-milling method for the synthesis of tetrahvdroquinoline derivatives via a wone-pot"three-component Diels-Alder reaction of anilines,aldehydes and alkenes catalyzed by ph...We reported an economic and practical ball-milling method for the synthesis of tetrahvdroquinoline derivatives via a wone-pot"three-component Diels-Alder reaction of anilines,aldehydes and alkenes catalyzed by phos-photungstic acid at room temperature.For this reaction,a simple 'one-pot'ball-milling operation was conducted,readily available starting materials were employed,'one-pot'conditions were applied,and the most important was to use inexpensive and environmentally friendly catalyst phosphotungstic acid.Various tetrahvdroquinolines,which might be potentially applicable in the pharmaceutical and biochemical areas,were conveniently synthesized in moderate to excellent yields.展开更多
In this work, the influence of graphite on the ball-milled TiCx was studied. The results show that the lattice parameter of TiCx is increased when TiCx particles are ball-milled with graphite, which indicates a decrea...In this work, the influence of graphite on the ball-milled TiCx was studied. The results show that the lattice parameter of TiCx is increased when TiCx particles are ball-milled with graphite, which indicates a decrease in the concentration of carbon vacancies in the TiCx. It is considered that this decrease in the concentration of carbon vacancies results from the diffusion of carbon atoms from graphite into the TiCx. When the TiCx is ball-milled with more graphite, the effectiveness of the ball-milling is better, and the diffusion process of carbon becomes much easier. Furthermore, besides diffusion into the TiCx, some graphite has transformed into amorphous carbon after the ball-milling.展开更多
The vigorous development of two-dimensional(2D)materials brings about numerous opportunities for lithiumion batteries(LIBs)due to their unique 2D layered structure,large specific surface area,outstanding mechanical an...The vigorous development of two-dimensional(2D)materials brings about numerous opportunities for lithiumion batteries(LIBs)due to their unique 2D layered structure,large specific surface area,outstanding mechanical and flexibility properties,etc.Modern technologies for production of 2D materials include but are not limited to mechanochemical(solid-state/liquid-phase)exfoliation,the solvothermal method and chemical vapor deposition.In this review,strategies leading to the production of 2D materials via solid-state mechanochemistry featuring traditional high energy ball-milling and Sichuan University patented pan-milling are highlighted.The mechanism involving exfoliation,edge selective carbon radical generation of the 2D materials is delineated and this is followed by detailed discussion on representative mechanochemical techniques for tailored and improved lithium-ion storage performance.In the light of the advantages of the solid-state mechanochemical method,there is great promise for the commercialization of 2D materials for the next-generation high performance LIBs.展开更多
To date, most of the research on electrodes for lithium sulfur batteries has been focused on the nanostructured sulfur cathodes and achieves significant success. However, from the viewpoint of manufacturers, the nanos...To date, most of the research on electrodes for lithium sulfur batteries has been focused on the nanostructured sulfur cathodes and achieves significant success. However, from the viewpoint of manufacturers, the nanostructured sulfur cathodes are not so promising, because of the low volumetric energy density and high cost. In this work, we obtained the low-cost, scalable, eco-friendly mass production of edge-functionalized acetylene black-sulfur(FAB-S) composites by high-energy ball-milling technique for lithium sulfur batteries. The as-prepared FAB-S composite can deliver a high initial discharge capacity of 1304 mAh/g and still remain a reversible capacity of 814 mAh/g after 200 cycles at a charge-discharge rate of 0.2 C in the voltage range of 1.7–2.7 V. The observed excellent electrochemical properties demonstrate that the cathodes obtained by the facile high-energy ball-milling method as the cathode for rechargeable Li-S batteries are of great potential because it used the sole conductive additive acetylene black(AB).Such improved properties could be attributed to the partially exfoliation of AB, which not only keeps the AB's inherent advantage, but also increases the specific surface area and forms chemical bonds between carbon and sulfur, resulting in the accumulation of the polysulfides intermediate through both the physical and chemical routes.展开更多
The oxide dispersion strengthened Mo alloys(ODS-Mo)prepared by traditional ball milling and subsequent sintering technique generally possess comparatively coarse Mo grains and large oxide particles at Mo grain boundar...The oxide dispersion strengthened Mo alloys(ODS-Mo)prepared by traditional ball milling and subsequent sintering technique generally possess comparatively coarse Mo grains and large oxide particles at Mo grain boundaries(GBs),which obviously suppress the corresponding strengthening effect of oxide addition.In this work,the Y_(2)O_(3) and TiC particles were simultaneously doped into Mo alloys using ball-milling and subsequent low temperature sintering.Accompanied by TiC addition,the Mo-Y_(2)O_(3) grains are sharply refined from 3.12 to 1.36μm.In particular,Y_(2)O_(3) and TiC can form smaller Y-Ti-O-C quaternary phase particles(~230 nm)at Mo GBs compared to single Y_(2)O_(3) particles(~420 nm),so as to these new formed Y-Ti-O-C particles can more effectively pin and hinder GBs movement.In addition to Y-Ti-O-C particles at GBs,Y_(2)O_(3),TiOx,and TiCx nanoparticles(<100 nm)also exist within Mo grains,which is significantly different from traditional ODS-Mo.The appearance of TiOx phase indicates that some active Ti within TiC can adsorb oxygen impurities of Mo matrix to form a new strengthening phase,thus strengthening and purifying Mo matrix.Furthermore,the pure Mo,Mo-Y_(2)O_(3),and Mo-Y_(2)O_(3)-TiC alloys have similar relative densities(97.4%-98.0%).More importantly,the Mo-Y_(2)O_(3)-TiC alloys exhibit higher hardness(HV0.2(425±25))compared to Mo-Y_(2)O_(3) alloys(HV0.2(370±25)).This work could provide a relevant strategy for the preparation of ultrafine Mo alloys by facile ball-milling.展开更多
The ball milling process and the CuWO_4-WO_3 precursors were investigated, and a new highly concentrated wet ball-milled process(HWM) was designed. W-20 wt% Cu composite powders with excellent sintering property were ...The ball milling process and the CuWO_4-WO_3 precursors were investigated, and a new highly concentrated wet ball-milled process(HWM) was designed. W-20 wt% Cu composite powders with excellent sintering property were synthesized by highly concentrated wet ballmilled process and co-reduction. The powders were characterized by scanning electron microscopy(SEM), X-ray diffraction(XRD), field electron transmission electron microscopy(FESEM) and laser-diffraction diameter tester.The results indicate that particle size of W03-CuO powder mixtures decreases to 390 nm rapidly with the milling time increasing to 5 h. The CuWO_4 precursors promote the microstructural homogeneity of W and Cu. W-Cu composite powders have a highly dispersed and well sintering property. The particle size of W-Cu powders milled by HWM for 5 h is about 680 nm. High-resolution transmission electron microscopy(HRTEM) result suggests that W phase and Cu phase are mixed at nanometer scale. The above W-Cu composite powders reach the relative density of about 99.3%.展开更多
Capacitive deionization(CDI)is a novel electrochemical water-treatment technology.The electrode material is an important factor in determining the ion separation efficiency.Activated carbon(AC)is extensively used as a...Capacitive deionization(CDI)is a novel electrochemical water-treatment technology.The electrode material is an important factor in determining the ion separation efficiency.Activated carbon(AC)is extensively used as an electrode material;however,there are still many deficiencies in commercial AC.We adopted a simple processing method,ball milling,to produce ball milled AC(BAC)to improve the physical and electrochemical properties of the original AC and desalination efficiency.The BAC was characterized in detail and used for membrane capacitive deionization(MCDI)and flow-electrode capacitive deionization(FCDI)electrode materials.After ball milling,the BAC obtained excellent pore structures and favorable surfaces for ion adsorption,which reduced electron transfer resistance and ion migration resistance in the electrodes.The optimal ball-milling time was 10 h.However,the improved effects of BAC as fixed electrodes and flow electrodes are different and the related mechanisms are discussed in detail.The average salt adsorption rates(ASAR)of FCDI and MCDI were improved by 134%and 17%,respectively,and the energy-normalized removal salt(ENRS)were enhanced by 21%and 53%,respectively.We believe that simple,low-cost,and environmentally friendly BAC has great potential for practical engineering applications of FCDI and MCDI.展开更多
High energy ball-milled iron sulfides with thin carb on layer coati ng(BM-FeS/C composites)were prepared by the simple and econo mical process.Ball-milled process,followed by carb on coati ng,reduced the particle size...High energy ball-milled iron sulfides with thin carb on layer coati ng(BM-FeS/C composites)were prepared by the simple and econo mical process.Ball-milled process,followed by carb on coati ng,reduced the particle size and increased the electrical con ductivity.Whe n employed as sodium-ion battery ano des,BM?F eS/C composites showed extremely high electrochemical performa nee with reversible specific capacity of 589.8 mAh·g^-1 after 100 cycles at a current density of 100 mA·g^-1.They also exhibited superior rate capabilities of 375.9 mAh·g^-1 even at 3.2 Ag^1 and 423.6 mAh·g^-1 at 1.5 Ag_1.X-ray absorptio n near edge structure an alysis con firmed the electrochemical pathway for con version reaction of BM-FeS/C composites.展开更多
We report the structural and photoluminescence(PL) properties of Nd^(3+)-doped Y_(2)O_(3)-SiO_(2) powders(Y_(2)O_(3)-SiO_(2):Nd^(3+)) as functions of annealing temperature and Nd^(3+) ion doping concentration.Y_(2)O_(...We report the structural and photoluminescence(PL) properties of Nd^(3+)-doped Y_(2)O_(3)-SiO_(2) powders(Y_(2)O_(3)-SiO_(2):Nd^(3+)) as functions of annealing temperature and Nd^(3+) ion doping concentration.Y_(2)O_(3)-SiO_(2):Nd^(3+)powders were prepared using the high-energy ball-milling(HEBM) method,and their structural and PL properties were investigated using X-ray diffraction(XRD),Fourier transform infrared(FTIR) spectroscopy,and PL spectroscopy.The XRD results reveal a cubic phase without impurities,and the peak broadening decreases with an increase in annealing temperature due to the increase in the crystallite size.The PL emission intensity increases with an increase in annealing temperature.The highest PL emission intensity is observed for the 300-min milled mixture annealed at 1000℃ for 1 h with a Nd^(3+) concentration of 1 mol%.The PL peaks excited by 800 nm radiation were detected,centered at 1080 nm(^(4)F_(3/2)→^(4)I_(11/2)) and 1350 nm(^(4)F_(3/2)→^(4)I_(13/2)).展开更多
Based on the excellent sodium ion mobility of sodium superionic conductor structures,Na_(3)V_(2)(PO_(4))_(3)materials have become promising cathode materials in sodium-ion batteries(SIBs).However,inadequate electronic...Based on the excellent sodium ion mobility of sodium superionic conductor structures,Na_(3)V_(2)(PO_(4))_(3)materials have become promising cathode materials in sodium-ion batteries(SIBs).However,inadequate electronic transport of Na_(3)V_(2)(PO_(4))_(3)limits the cycling stability and rate performances in SIBs.In this work,high-performance conductive carbon-coated Na_(3)V_(2)(PO_(4))_(3)materials are obtained via a simple and facile ball-milling assisted solid-state method by utilizing citric acid as carbon sources.The carbon-coated composite electrodes display a high initial specific capacity of 111.6 mAh·g^(-1),and the specific capacity could retention reach 92.83%after 100 cycles at 1C with the high coulombic efficiency(99.95%).More importantly,the capacity of conductive carbon-coated nano-sized Na_(3)V_(2)(PO_(4))_(3)can remain 48.5 mAh·g^(-1) at 10℃after 3000 cycles(initial capacity of 101.2 mAh·g^(-1)).At the same time,high coulombic efficiency(near 100%)has little decay even at a high rate of 20℃during 1000 cycles,demonstrating the excellent cycling stability and remarkable rate performances,and showing potential in largescale productions and applications.展开更多
Brønsted acid site(S/Cl)-functional carbon materials were prepared by ball-milling(bm)L-cysteine and ammonium chloride to form chemical complex solids,by post-heat treatment(Q)of the solids at 500°C under a ...Brønsted acid site(S/Cl)-functional carbon materials were prepared by ball-milling(bm)L-cysteine and ammonium chloride to form chemical complex solids,by post-heat treatment(Q)of the solids at 500°C under a nitrogen gas atmosphere to stabilize and fortify amino and functional group solid structures and by post-oxidative treatment with H_(2)O_(2)to add Brønsted acidity.The as-prepared carbon materials(S/Cl@bm_(x)Q_(y);x,y in hours)contained Brønsted acid sites(sul-fonates,chlorides),oxygen-containing groups(-COOH,-OH)and amino functional groups.The S/Cl@bm_(x)Q_(y)materials were applied as catalysts to promote conversion of fructose in ethanol solvent to 5-hydroxymethylfurfural(5-HMF)and 5-ethoxymethylfurfural(5-EMF).Among the carbon materials,S/Cl@bm_(3)Q_(1)gave 5-EMF and 5-HMF yields of 67.0%and 22.8%,respectively,in pure ethanol at 140℃for 24 h reaction time,while a reaction time of 18 h gave total 5-EMF and 5-HMF yields of 96.4%.Dimethyl sulfoxide(DMSO)was applied as additive to the ethanol-fructose-S/Cl@bm_(3)Q_(1)reaction system which showed that 5-HMF product selectivity could be controlled with DMSO concentration.The protocol developed allows simple preparation of func-tional carbon materials that have high catalytic activity and are effective for conversion of fructose to 5-HMF and 5-EMF in ethanol.展开更多
Due to the relatively sluggish charge carrier separation in metal sulfides,the photocatalytic activity of them is still far lower than expected.Herein,sulfur vacancies and in-plane SnS_(2)/SnO_(2) heterojunction were ...Due to the relatively sluggish charge carrier separation in metal sulfides,the photocatalytic activity of them is still far lower than expected.Herein,sulfur vacancies and in-plane SnS_(2)/SnO_(2) heterojunction were successfully introduced into the SnS_(2) nanosheets through high energy ball-milling.These defective structures were studied by the electron paramagnetic resonance,Raman spectra,X-ray photoelectron spectroscopy,and high-resolution transmission electron microscope analyses.The sulfur vacancies and in-plane heterojunctions strongly accelerate the separation of photoexcited electron-hole pairs,as confirmed by the photo luminesce nce emission spectra and time-resolved photoluminescence decay spectra.The introduction of sulfur vacancies and in-plane heterojunction in SnS_(2) nanosheets results in roughly six times higher photodegrading rate for methyl orange and four times higher photocatalytic reduction rate of Cr6+than those of pure SnS_(2) nanosheets.展开更多
In recent years,high-entropy alloys(HEAs)have received more and more attention due to their unique microstructure and properties.Several researchers have reported that some ball-milled(BM)HEAs powders possess prominen...In recent years,high-entropy alloys(HEAs)have received more and more attention due to their unique microstructure and properties.Several researchers have reported that some ball-milled(BM)HEAs powders possess prominent decolorization performance for azo dyes.Three kinds of Co-free HEA powders(AlCrFeMn,AlCrFeNi and FeCrNiMn)have been synthesized by ball milling in this work,of which AlCrFeMn shows the best decolorization efficiency for DB6 aqueous solution.However,at this time,the BM HEAs are in powder state and not easy to be reused,so the loss rate of the powders is high during the reaction.Sometimes,the reaction between reacted the powders and the dye solution is too fast to control.While,in order to solve these problems,this work proposes to immobilize bare BM AlCrFeMn HEA powders in calcium alginate beads(CAB s)by electrospray and microfluidics.Through four cycles of reaction,the loss rate of the AlCrFeMn powders can be reduced from 40 to 5 wt%if the powders are immobilized by CABs with an average diameter of 0.55 mm obtained at the DC voltage of 30 kV.In addition,in the four cycles of experiment,the AlCrFeMn HEA-CABs with an average diameter of0.55 mm shows better stability and easier separation than that of the bare AlCrFeMn powders.These findings provide new ideas for HEAs to decolorize azo dyes and are of great significance for protecting freshwater resources.展开更多
Graphene-based composite aerogel doped with other low-cost materials can reduce the cost and promote the use in water treatment.This work prepared ball-milled biochar/reduced graphene oxide aerogel(BC/rGA)using GO and...Graphene-based composite aerogel doped with other low-cost materials can reduce the cost and promote the use in water treatment.This work prepared ball-milled biochar/reduced graphene oxide aerogel(BC/rGA)using GO and low-cost ball-milled biochar(BC)in a certain proportion with the freeze-thawing technique and sol-gel method,and applied BC/rGA on the Cr(Ⅵ)removal from aquatic environments.The characterization results showed that aerogel had a honeycomb briquette three-dimension(3D)and mesoporous structure with interconnected pores,and proved the preparation progress of aerogel in principle.Compared with GO,rGA and BC/rGA had better adsorption performance with 3D structure and well-developed pores,and BC/rGA with the mixture ratio of BC and GO of 1:4 was more appropriate.The adsorption kinetics data of rGA and BC/rGA_((1:4))were fitting well with the pseudo-second-order model(R^(2)>0.951),and the isotherm adsorption results were fitting the Langmuir model well(R^(2)>0.974).The results demonstrated that the adsorption process was monolayer and endothermic adsorption involving chemisorp-tion.Additionally,the adsorption capacities of rGA and BC/rGA_((1:4))at solution pH 2 were 3.71 and 3.89 times greater than those at solution pH 8,respectively.High background ion strength and low temperature slightly inhibited the adsorption of Cr(Ⅵ)by both rGA and BC/rGA_((1:4)).The adsorption mechanisms of Cr(Ⅵ)on rGA and BC/rGA_((1:4))were electrostatic interaction,reduction and ion exchange.The use of BC/rGA could reduce the cost and promote the green reuse of agricultural waste.Overall,BC/rGA could be used as a promising green adsorbent alternative for the feasible treatment of heavy metal contaminated water.展开更多
基金supported by the Surface Project of Local Development in Science and Technology Guided by Central Government(No.2021ZYD0041)the National Natural Science Foundation of China(No.52074227)。
文摘To deal with the growing electromagnetic hazards,herein a Co@CuFe_(2)O_(4)absorbing agent with excellent impedance matching at thin thickness was obtained via an innovative route of ball-milling assisted chemical precipitation and annealing.The as-prepared composite possesses excellent interface polarization ability due to sufficient contact between CuFe_(2)O_(4)NPs and flat Co,and this compressed Co lamella can also provide sufficient eddy current loss.Moreover,the dipole polarization,electron hopping/conduction,and structural scattering also contribute to the broadband microwave absorption of the composite.Thus,the minimum microwave reflection loss achieves-35.56 d B at12.93 GHz for 1.8 mm thickness,and the broadest efficient absorption bandwidth can reach 6.74 GHz for a thinner thickness of 1.72 mm.The preparation method reported here can be referenced as a new-type route to manufacture electromagnetic absorbers with outstanding performance.
基金This work has been supported by the Xinjiang Uygur Autonomous Region Key R&D Program(2017B02012)the Xinjiang University Natural Science Foundation Project(BS160221).
文摘The Ni-Al2O3 catalyst was prepared by the mechanochemical method in combination with a planetary ballmilling machine.Effect of milling time on the crystal structure,the reduction characteristics and the catalytic performance of Ni-Al2O3 catalyst for hydrogenation of 1,4-butynediol to produce 1,4-butenediol were investigated.The catalysts were characterized by PSD,EDX,XRD,H2-TPR,BET,TEM,and NH3-TPD methods.Results showed that the MCt2.5 catalyst treated at a ball milling time of 2.5 h could form a smallest particle size of 191.0 nm.The evaluation experiments revealed that the activity of the prepared catalyst increased at first and then reached a constant value with the extension of ballmilling time.The BYD conversion,BED selectivity and yield on the MCt2.5 catalyst reached 35.63%,33.48%and 32.46%,respectively,which were higher than those obtained by other samples.The excellent performance of MCt2.5 sample is mainly related to the following three reasons from characterization results.Firstly,it has a smallest particle size of 191.0 nm;and then,the surface acidity(in terms of strong acids)of the catalyst was weaker than other catalysts;and eventually,the loading amount(23.84%)of the active component Ni exceeded the theoretical value(20%).
基金financial support of the National Natural Science Foundation(Nos.51373191,51472253)
文摘Cellulose is a linear polymer consisting of D-anhydroglucose units joined by β-1,4-glycosidic linkages. The densely packed cellulose molecular chain forms crystalline cellulose through strong hydrogen bonding. Owing to its chemical tunability and excellent mechanical resistance, nanocellulose is widely used in everyday life and the industrial sector. In this work, cellulose materials were nanoprocessed by mechanical ball-milling(1) in polar solvents(N,N-dimethylformamide or dimethyl sulfoxide) with esterification or(2) in hydrophobic agents(polydimethylsiloxane or polytetrafluoroethylene) with different molecular weights. Cellulose nanofibers and nanosheets with different hydrophilic and hydrophobic properties were obtained, and the mechanism of cellulose disintegration along a crystallographic plane induced by mechanical force and the polarity condition were discussed. This work affords a new way to manipulate the morphology and properties of nanocellulose.
文摘Manganese (Mn) is an essential element for human body. However, elevated concentration of manganese causes severe problem and disease. Acid mine drainage (AMD), wastewater generated due to open-pit mining, commonly contains Mn with exceeded concentration. This study is to investigate the improvement of ball-milling modified Indonesian natural bentonite (INB) for manganese (Mn) removal from AMD and to increase the pH through batch and column sorption test as a passive treatment system approach. The batch sorption test result showed the maximum Mn adsorbed (Qm) on INB from the Langmuir model increased from 4.69 to 17.12 mg/g after milling. The column sorption test result also showed the amount of Mn adsorbed on INB until breakthrough time (qu) and until saturation time (q) increased after milling. The qu increased from 1.27 to 10.06 mg/g, and the q increased from 4.55 to 12.91 mg/g. The mass transfer zone (MTZ) became significantly shorter after milling from 0.22 to 0.07 cm. The Thomas model exhibited the equilibrium uptake of Mn (q0) increased after milling from 3.91 to 13.72 mg/g. In equilibrium condition, both unmilled and milled INB showed the pH increased from ≈3 to 8.
基金support by National Natural Science Foundation of China (No.31670591)the fellowship of China Postdoctoral Science Foundation (No.2022M711229)+1 种基金Natural Science Foundation of Jiangsu Province (No.BK20160928)supported by the South Eastern Regional Sun Grant Centre and AgResearch at the University of Tennessee.
文摘Water-soluble lignin-carbohydrate complex(LCC)rich in polysaccharides exhibits benign in vitro antioxidant activities and distinguishes high biocompatibility from lignin-rich LCC and lignin.However,the antioxidant activity of water-soluble LCCs remains to be improved and its structure-antioxidant relationship is still uncertain.Herein,structurally diversified water-soluble LCCs were isolated under different ball-milling pretreatment durations(4,6,8 h),extraction pathways(ho-mogeneous and heterogeneous),and isolation routines(water extracts and residues after water extraction).Their structures were characterized by wet chemistry,chromatography and spec-troscopies.Antioxidant activities were evaluated by ferric reducing antioxidant power and 1,1-diphenyl-2-picrylhydrazyl radicals scavenging rate(RDPPH).Results show that altering ball-milling duration and isolation procedures cause varied structures and antioxidant activities of the water-soluble LCCs.Specifically,prolonging ball-milling duration to 8 hours and homogeneous extrac-tion can enhance their antioxidant activity through releasing more phenolic structures and pro-moting the extraction of high-molecular-weight LCCs via reducing mass-transfer resistance,re-spectively.As a result,the RDPPH of water-soluble LCCs reaches up to 97.35%,which is associated with the arabinan content with statistical significance(P<0.05).This study provides new insights into the structure-antioxidation relationship of herbaceous LCC as potential antioxidants.
基金Supported by the Natural Science Foundation of Shandong Province,China(Nos.ZR2019QB022,ZR2019MB043).
文摘We reported an economic and practical ball-milling method for the synthesis of tetrahvdroquinoline derivatives via a wone-pot"three-component Diels-Alder reaction of anilines,aldehydes and alkenes catalyzed by phos-photungstic acid at room temperature.For this reaction,a simple 'one-pot'ball-milling operation was conducted,readily available starting materials were employed,'one-pot'conditions were applied,and the most important was to use inexpensive and environmentally friendly catalyst phosphotungstic acid.Various tetrahvdroquinolines,which might be potentially applicable in the pharmaceutical and biochemical areas,were conveniently synthesized in moderate to excellent yields.
基金supported by the National Natural Science Fundation of China (grant No. 51071097)the Fundamental Research Fund for the Central Universities of China (grant No. 11QG67)
文摘In this work, the influence of graphite on the ball-milled TiCx was studied. The results show that the lattice parameter of TiCx is increased when TiCx particles are ball-milled with graphite, which indicates a decrease in the concentration of carbon vacancies in the TiCx. It is considered that this decrease in the concentration of carbon vacancies results from the diffusion of carbon atoms from graphite into the TiCx. When the TiCx is ball-milled with more graphite, the effectiveness of the ball-milling is better, and the diffusion process of carbon becomes much easier. Furthermore, besides diffusion into the TiCx, some graphite has transformed into amorphous carbon after the ball-milling.
基金financially supported by the National Natural Science Foundation of China(No.51933007,51673123)the National Key R&D Program of China(No.2017YFE0111500)the Program for Featured Directions of Engineering Multidisciplines of Sichuan University(No.2020SCUNG203)。
文摘The vigorous development of two-dimensional(2D)materials brings about numerous opportunities for lithiumion batteries(LIBs)due to their unique 2D layered structure,large specific surface area,outstanding mechanical and flexibility properties,etc.Modern technologies for production of 2D materials include but are not limited to mechanochemical(solid-state/liquid-phase)exfoliation,the solvothermal method and chemical vapor deposition.In this review,strategies leading to the production of 2D materials via solid-state mechanochemistry featuring traditional high energy ball-milling and Sichuan University patented pan-milling are highlighted.The mechanism involving exfoliation,edge selective carbon radical generation of the 2D materials is delineated and this is followed by detailed discussion on representative mechanochemical techniques for tailored and improved lithium-ion storage performance.In the light of the advantages of the solid-state mechanochemical method,there is great promise for the commercialization of 2D materials for the next-generation high performance LIBs.
基金supported by the National Natural Science Foundation of China(Grant Nos.51671074,51602079,51572060,and 51502062)the Fundamental Research Funds for the Central Universities(No.HIT.BRETIII.201224 and 201312)+1 种基金Program for Innovation Research of Science in Harbin Institute of Technology(PIRS of HIT-No.201506)support from the Excellent Youth Foundation of Heilongjiang Scientific Committee(No.JC2015010)
文摘To date, most of the research on electrodes for lithium sulfur batteries has been focused on the nanostructured sulfur cathodes and achieves significant success. However, from the viewpoint of manufacturers, the nanostructured sulfur cathodes are not so promising, because of the low volumetric energy density and high cost. In this work, we obtained the low-cost, scalable, eco-friendly mass production of edge-functionalized acetylene black-sulfur(FAB-S) composites by high-energy ball-milling technique for lithium sulfur batteries. The as-prepared FAB-S composite can deliver a high initial discharge capacity of 1304 mAh/g and still remain a reversible capacity of 814 mAh/g after 200 cycles at a charge-discharge rate of 0.2 C in the voltage range of 1.7–2.7 V. The observed excellent electrochemical properties demonstrate that the cathodes obtained by the facile high-energy ball-milling method as the cathode for rechargeable Li-S batteries are of great potential because it used the sole conductive additive acetylene black(AB).Such improved properties could be attributed to the partially exfoliation of AB, which not only keeps the AB's inherent advantage, but also increases the specific surface area and forms chemical bonds between carbon and sulfur, resulting in the accumulation of the polysulfides intermediate through both the physical and chemical routes.
基金financially supported by the National Natural Science Foundation of China (Nos. 52171044 and 51804218)the Innovation and Entrepreneurship Training Program for College Students in Fujian Province, China (No. S202111312029)
文摘The oxide dispersion strengthened Mo alloys(ODS-Mo)prepared by traditional ball milling and subsequent sintering technique generally possess comparatively coarse Mo grains and large oxide particles at Mo grain boundaries(GBs),which obviously suppress the corresponding strengthening effect of oxide addition.In this work,the Y_(2)O_(3) and TiC particles were simultaneously doped into Mo alloys using ball-milling and subsequent low temperature sintering.Accompanied by TiC addition,the Mo-Y_(2)O_(3) grains are sharply refined from 3.12 to 1.36μm.In particular,Y_(2)O_(3) and TiC can form smaller Y-Ti-O-C quaternary phase particles(~230 nm)at Mo GBs compared to single Y_(2)O_(3) particles(~420 nm),so as to these new formed Y-Ti-O-C particles can more effectively pin and hinder GBs movement.In addition to Y-Ti-O-C particles at GBs,Y_(2)O_(3),TiOx,and TiCx nanoparticles(<100 nm)also exist within Mo grains,which is significantly different from traditional ODS-Mo.The appearance of TiOx phase indicates that some active Ti within TiC can adsorb oxygen impurities of Mo matrix to form a new strengthening phase,thus strengthening and purifying Mo matrix.Furthermore,the pure Mo,Mo-Y_(2)O_(3),and Mo-Y_(2)O_(3)-TiC alloys have similar relative densities(97.4%-98.0%).More importantly,the Mo-Y_(2)O_(3)-TiC alloys exhibit higher hardness(HV0.2(425±25))compared to Mo-Y_(2)O_(3) alloys(HV0.2(370±25)).This work could provide a relevant strategy for the preparation of ultrafine Mo alloys by facile ball-milling.
基金financially supported by the National Natural Science Foundation of China (No. 51274246)
文摘The ball milling process and the CuWO_4-WO_3 precursors were investigated, and a new highly concentrated wet ball-milled process(HWM) was designed. W-20 wt% Cu composite powders with excellent sintering property were synthesized by highly concentrated wet ballmilled process and co-reduction. The powders were characterized by scanning electron microscopy(SEM), X-ray diffraction(XRD), field electron transmission electron microscopy(FESEM) and laser-diffraction diameter tester.The results indicate that particle size of W03-CuO powder mixtures decreases to 390 nm rapidly with the milling time increasing to 5 h. The CuWO_4 precursors promote the microstructural homogeneity of W and Cu. W-Cu composite powders have a highly dispersed and well sintering property. The particle size of W-Cu powders milled by HWM for 5 h is about 680 nm. High-resolution transmission electron microscopy(HRTEM) result suggests that W phase and Cu phase are mixed at nanometer scale. The above W-Cu composite powders reach the relative density of about 99.3%.
基金supported by the Science and Technology Project of Hebei Education Department(No.QN2022038)the State Key Joint Laboratory of Environment Simulation and Pollution Control(No.22K05ESPCT)the Hebei University of Science and Technology Graduate Innovation Funding Program(No.XJCXZZSS2022009).
文摘Capacitive deionization(CDI)is a novel electrochemical water-treatment technology.The electrode material is an important factor in determining the ion separation efficiency.Activated carbon(AC)is extensively used as an electrode material;however,there are still many deficiencies in commercial AC.We adopted a simple processing method,ball milling,to produce ball milled AC(BAC)to improve the physical and electrochemical properties of the original AC and desalination efficiency.The BAC was characterized in detail and used for membrane capacitive deionization(MCDI)and flow-electrode capacitive deionization(FCDI)electrode materials.After ball milling,the BAC obtained excellent pore structures and favorable surfaces for ion adsorption,which reduced electron transfer resistance and ion migration resistance in the electrodes.The optimal ball-milling time was 10 h.However,the improved effects of BAC as fixed electrodes and flow electrodes are different and the related mechanisms are discussed in detail.The average salt adsorption rates(ASAR)of FCDI and MCDI were improved by 134%and 17%,respectively,and the energy-normalized removal salt(ENRS)were enhanced by 21%and 53%,respectively.We believe that simple,low-cost,and environmentally friendly BAC has great potential for practical engineering applications of FCDI and MCDI.
文摘High energy ball-milled iron sulfides with thin carb on layer coati ng(BM-FeS/C composites)were prepared by the simple and econo mical process.Ball-milled process,followed by carb on coati ng,reduced the particle size and increased the electrical con ductivity.Whe n employed as sodium-ion battery ano des,BM?F eS/C composites showed extremely high electrochemical performa nee with reversible specific capacity of 589.8 mAh·g^-1 after 100 cycles at a current density of 100 mA·g^-1.They also exhibited superior rate capabilities of 375.9 mAh·g^-1 even at 3.2 Ag^1 and 423.6 mAh·g^-1 at 1.5 Ag_1.X-ray absorptio n near edge structure an alysis con firmed the electrochemical pathway for con version reaction of BM-FeS/C composites.
基金The authors would like to thank the financial support by a 2019 research fund from Chosun University.
文摘We report the structural and photoluminescence(PL) properties of Nd^(3+)-doped Y_(2)O_(3)-SiO_(2) powders(Y_(2)O_(3)-SiO_(2):Nd^(3+)) as functions of annealing temperature and Nd^(3+) ion doping concentration.Y_(2)O_(3)-SiO_(2):Nd^(3+)powders were prepared using the high-energy ball-milling(HEBM) method,and their structural and PL properties were investigated using X-ray diffraction(XRD),Fourier transform infrared(FTIR) spectroscopy,and PL spectroscopy.The XRD results reveal a cubic phase without impurities,and the peak broadening decreases with an increase in annealing temperature due to the increase in the crystallite size.The PL emission intensity increases with an increase in annealing temperature.The highest PL emission intensity is observed for the 300-min milled mixture annealed at 1000℃ for 1 h with a Nd^(3+) concentration of 1 mol%.The PL peaks excited by 800 nm radiation were detected,centered at 1080 nm(^(4)F_(3/2)→^(4)I_(11/2)) and 1350 nm(^(4)F_(3/2)→^(4)I_(13/2)).
基金This work was financially supported by the National Key Research and Development Program of China(No.2017YFB0102000)Major Program of the National Natural Science Foundation of China(No.51890865)the State Key Program of National Natural Science of China(No.61835014).
文摘Based on the excellent sodium ion mobility of sodium superionic conductor structures,Na_(3)V_(2)(PO_(4))_(3)materials have become promising cathode materials in sodium-ion batteries(SIBs).However,inadequate electronic transport of Na_(3)V_(2)(PO_(4))_(3)limits the cycling stability and rate performances in SIBs.In this work,high-performance conductive carbon-coated Na_(3)V_(2)(PO_(4))_(3)materials are obtained via a simple and facile ball-milling assisted solid-state method by utilizing citric acid as carbon sources.The carbon-coated composite electrodes display a high initial specific capacity of 111.6 mAh·g^(-1),and the specific capacity could retention reach 92.83%after 100 cycles at 1C with the high coulombic efficiency(99.95%).More importantly,the capacity of conductive carbon-coated nano-sized Na_(3)V_(2)(PO_(4))_(3)can remain 48.5 mAh·g^(-1) at 10℃after 3000 cycles(initial capacity of 101.2 mAh·g^(-1)).At the same time,high coulombic efficiency(near 100%)has little decay even at a high rate of 20℃during 1000 cycles,demonstrating the excellent cycling stability and remarkable rate performances,and showing potential in largescale productions and applications.
基金the Iwatani Naoji Foundation and from the Materials Processing Science project("Mate-realize")of the Ministry of Education,Culture,Sports,Science and Technology(MEXT)(No.JPMXP0219192801).
文摘Brønsted acid site(S/Cl)-functional carbon materials were prepared by ball-milling(bm)L-cysteine and ammonium chloride to form chemical complex solids,by post-heat treatment(Q)of the solids at 500°C under a nitrogen gas atmosphere to stabilize and fortify amino and functional group solid structures and by post-oxidative treatment with H_(2)O_(2)to add Brønsted acidity.The as-prepared carbon materials(S/Cl@bm_(x)Q_(y);x,y in hours)contained Brønsted acid sites(sul-fonates,chlorides),oxygen-containing groups(-COOH,-OH)and amino functional groups.The S/Cl@bm_(x)Q_(y)materials were applied as catalysts to promote conversion of fructose in ethanol solvent to 5-hydroxymethylfurfural(5-HMF)and 5-ethoxymethylfurfural(5-EMF).Among the carbon materials,S/Cl@bm_(3)Q_(1)gave 5-EMF and 5-HMF yields of 67.0%and 22.8%,respectively,in pure ethanol at 140℃for 24 h reaction time,while a reaction time of 18 h gave total 5-EMF and 5-HMF yields of 96.4%.Dimethyl sulfoxide(DMSO)was applied as additive to the ethanol-fructose-S/Cl@bm_(3)Q_(1)reaction system which showed that 5-HMF product selectivity could be controlled with DMSO concentration.The protocol developed allows simple preparation of func-tional carbon materials that have high catalytic activity and are effective for conversion of fructose to 5-HMF and 5-EMF in ethanol.
基金National Key Research And Development Program(No.2016YFB0901600)CAS Center for Excellence in Superconducting Electronics+3 种基金the Key Research Program of Chinese Academy of Sciences(Nos.QYZDJ-SSWJSC013 and KGZD-EW-T06)National Natural Science Foundation of China(Nos.21871008 and 21801247)Jingdezhen Science and Technology Bureau(No.20192GYZD008-21)Science Foundation for Youth Scholar of State Key Laboratory of High Performance Ceramics and Superfine Microstructures(No.SKL 201804)。
文摘Due to the relatively sluggish charge carrier separation in metal sulfides,the photocatalytic activity of them is still far lower than expected.Herein,sulfur vacancies and in-plane SnS_(2)/SnO_(2) heterojunction were successfully introduced into the SnS_(2) nanosheets through high energy ball-milling.These defective structures were studied by the electron paramagnetic resonance,Raman spectra,X-ray photoelectron spectroscopy,and high-resolution transmission electron microscope analyses.The sulfur vacancies and in-plane heterojunctions strongly accelerate the separation of photoexcited electron-hole pairs,as confirmed by the photo luminesce nce emission spectra and time-resolved photoluminescence decay spectra.The introduction of sulfur vacancies and in-plane heterojunction in SnS_(2) nanosheets results in roughly six times higher photodegrading rate for methyl orange and four times higher photocatalytic reduction rate of Cr6+than those of pure SnS_(2) nanosheets.
基金the National Natural Science Foundation of China(Grant No.51671056)Jiangsu Key Laboratory for Advanced Metallic Materials(Grant No.BM2007204)。
文摘In recent years,high-entropy alloys(HEAs)have received more and more attention due to their unique microstructure and properties.Several researchers have reported that some ball-milled(BM)HEAs powders possess prominent decolorization performance for azo dyes.Three kinds of Co-free HEA powders(AlCrFeMn,AlCrFeNi and FeCrNiMn)have been synthesized by ball milling in this work,of which AlCrFeMn shows the best decolorization efficiency for DB6 aqueous solution.However,at this time,the BM HEAs are in powder state and not easy to be reused,so the loss rate of the powders is high during the reaction.Sometimes,the reaction between reacted the powders and the dye solution is too fast to control.While,in order to solve these problems,this work proposes to immobilize bare BM AlCrFeMn HEA powders in calcium alginate beads(CAB s)by electrospray and microfluidics.Through four cycles of reaction,the loss rate of the AlCrFeMn powders can be reduced from 40 to 5 wt%if the powders are immobilized by CABs with an average diameter of 0.55 mm obtained at the DC voltage of 30 kV.In addition,in the four cycles of experiment,the AlCrFeMn HEA-CABs with an average diameter of0.55 mm shows better stability and easier separation than that of the bare AlCrFeMn powders.These findings provide new ideas for HEAs to decolorize azo dyes and are of great significance for protecting freshwater resources.
基金the National Natural Science Foundation of China(Grant No.21377074).
文摘Graphene-based composite aerogel doped with other low-cost materials can reduce the cost and promote the use in water treatment.This work prepared ball-milled biochar/reduced graphene oxide aerogel(BC/rGA)using GO and low-cost ball-milled biochar(BC)in a certain proportion with the freeze-thawing technique and sol-gel method,and applied BC/rGA on the Cr(Ⅵ)removal from aquatic environments.The characterization results showed that aerogel had a honeycomb briquette three-dimension(3D)and mesoporous structure with interconnected pores,and proved the preparation progress of aerogel in principle.Compared with GO,rGA and BC/rGA had better adsorption performance with 3D structure and well-developed pores,and BC/rGA with the mixture ratio of BC and GO of 1:4 was more appropriate.The adsorption kinetics data of rGA and BC/rGA_((1:4))were fitting well with the pseudo-second-order model(R^(2)>0.951),and the isotherm adsorption results were fitting the Langmuir model well(R^(2)>0.974).The results demonstrated that the adsorption process was monolayer and endothermic adsorption involving chemisorp-tion.Additionally,the adsorption capacities of rGA and BC/rGA_((1:4))at solution pH 2 were 3.71 and 3.89 times greater than those at solution pH 8,respectively.High background ion strength and low temperature slightly inhibited the adsorption of Cr(Ⅵ)by both rGA and BC/rGA_((1:4)).The adsorption mechanisms of Cr(Ⅵ)on rGA and BC/rGA_((1:4))were electrostatic interaction,reduction and ion exchange.The use of BC/rGA could reduce the cost and promote the green reuse of agricultural waste.Overall,BC/rGA could be used as a promising green adsorbent alternative for the feasible treatment of heavy metal contaminated water.
