Polystyrene resins(PS)have been practical ion exchangers for radionuclides removal from water.However,nonspecific effects of ion exchange groups continue to be a major obstacle for emergency treatment with coexisting ...Polystyrene resins(PS)have been practical ion exchangers for radionuclides removal from water.However,nonspecific effects of ion exchange groups continue to be a major obstacle for emergency treatment with coexisting ions of high concentrations.The selectivity for Cs+enables zirconium phosphate(ZrP)to be the most promising inorganic sorbent for radioactive cesium extraction,despite being difficult to synthesize and causing excessive pressure loss in fixed-bed reactors due to fine powder.Herein,through facile confined crystallization in host macropores,we prepared PS confinedα-ZrP nanocrystalline(ZrP-PS).Size-screen sorption of layeredα-ZrP and sulfonic acid group preconcentration of PS synergistically enable a considerably higher Cs+affinity of ZrP-PS than PS,as confirmed by X-ray photoelectron spectroscopy(XPS)analysis.ZrP-PS demonstrated remarkable cesium sequestration performance in both batch and continuous experiments,with a high adsorption capacity of 269.58 mg/g,a rapid equilibrium within 80 min,and a continuous effluent volume of 2300 L/kg sorbents.Given the excellent selectivity for Cs+and flexibility to separate from treated water,ZrP-PS holds great promise as purification packages for the emergency treatment of radioactively contaminated water.展开更多
To surmount the obstacles of traditional Fenton method and synchronously utilize Cu^(2+)and polyphenol in water,an improved Fenton-like reaction applying calcium peroxide(CaO_(2))as H_(2)O_(2)source and regulating by ...To surmount the obstacles of traditional Fenton method and synchronously utilize Cu^(2+)and polyphenol in water,an improved Fenton-like reaction applying calcium peroxide(CaO_(2))as H_(2)O_(2)source and regulating by the complex of Cu^(2+)-tartaric acid(TA,a representative of polyphenol)was constructed.A typical antibiotic,metronidazole(MTZ)could be effectively eliminated by the Cu^(2+)/TA/CaO_(2)system,and the optimized parameters were as follows:0.1 mmol/L Cu^(2+),2 mmol/L TA,2 mmol/L CaO_(2),and initial pH5.UV spectrum confirmed the formation of Cu^(2+)-TA complex,which promoted the Cu^(2+)/Cu+circulation through decreasing the Cu^(2+)/Cu^(+) couple redox potential,which further enhanced the H_(2)O_(2)decomposition and the formation of reactive species.Hydroxyl radical was dominant for MTZ degradation,followed by oxygen and superoxide radical.The degradation intermediates of MTZ were detected and their evolution way was speculated.Furthermore,the ternary process showed a wide p H tolerance(3–8)for removing MTZ and broad applicability for eliminating other dyes and antibiotics.This work provided a reference for Cu-based Fenton-like strategy for organic wastewater settlement.展开更多
In some industrial wastewater,heavy metals combine with organic complexing agents to form heavy metal complexes(HMCs).These HMCs can be difficult to decompose and remove through conventional techniques due to their hi...In some industrial wastewater,heavy metals combine with organic complexing agents to form heavy metal complexes(HMCs).These HMCs can be difficult to decompose and remove through conventional techniques due to their higher stability than free heavy metal ions.In recent years,persulfate based advanced oxidation processes(PS-based AOPs)have been recognized as a viable technique for HMCs degradation.Nevertheless,a comprehensive and in-depth understanding of the relevant HMCs decomplexation mechanisms in PS-based AOPs is still lacking.This review delineates the current progress of HMCs decomplexation in PS-based AOPs.We discuss the distinctions between the two widely used oxidant types in PS-based AOPs techniques.Moreover,we summarize and highlight the decomplexation mechanisms based on electron and energy transfer,and degradation pathways of HMCs.We also emphasize the effects of environmental water constituents,namely p H,inorganic ions,and natural organic matter(NOM),on HMCs decomplexation.Ultimately,we identify the existing challenges and perspectives that will steer the direction of advancing PS-based AOPs to remove HMCs.展开更多
The problem of triangular lattice formation in robot swarms has been investigated extensively in the literature,but the existing algorithms can hardly keep comparative performance from swarm simulation to real multi‐...The problem of triangular lattice formation in robot swarms has been investigated extensively in the literature,but the existing algorithms can hardly keep comparative performance from swarm simulation to real multi‐robot scenarios,due to the limited computation power or the restricted field of view(FOV)of robot sensors.Eventually,a distributed solution for triangular lattice formation in robot swarms with minimal sensing and computation is proposed and developed in this study.Each robot is equipped with a sensor with a limited FOV providing only a ternary digit of information about its neighbouring environment.At each time step,the motion command is directly determined by using only the ternary sensing result.The circular motions with a certain level of randomness lead the robot swarms to stable triangular lattice formation with high quality and robustness.Extensive numerical simulations and multi‐robot experiments are conducted.The results have demonstrated and validated the efficiency of the proposed approach.The minimised sensing and computation requirements pave the way for massive deployment at a low cost and implementation within swarms of miniature robots.展开更多
Amyloid nanofibrils(ANFs)are supramolecular polymers originally classified as pathological markers in various human degenerative diseases.However,in recent years,ANFs have garnered greater interest and are regarded as...Amyloid nanofibrils(ANFs)are supramolecular polymers originally classified as pathological markers in various human degenerative diseases.However,in recent years,ANFs have garnered greater interest and are regarded as nature-based sustainable biomaterials in environmental science,material engineering,and nanotechnology.On a laboratory scale,ANFs can be produced from food proteins via protein unfolding,misfolding,and hydrolysis.Furthermore,ANFs have specific structural characteristics such as a high aspect ratio,good rigidity,chemical stability,and a controllable sequence.These properties make them a promising functional material in water decontamination research.As a result,the fabrication and application of ANFs and their composites in water purification have recently gained considerable attention.Despite the large amount of literature in this field,there is a lack of systematic review to assess the gap in using ANFs and their composites to remove contaminants from water.This review discusses significant advancements in design techniques as well as the physicochemical properties of ANFs-based composites.We also emphasize the current progress in using ANFs-based composites to remove inorganic,organic,and biological contaminants.The interaction mechanisms between ANFs-based composites and contaminants are also highlighted.Finally,we illustrate the challenges and opportunities associated with the future preparation and application of ANFs-based composites.We anticipate that this review will shed new light on the future design and use of ANFs-based composites.展开更多
Constructing a Z-scheme is a significant approach to improve the separation of photogene rated carriers for effective organic pollutant degradation.Herein,a BiVO4/ZnIn2S4(BZ) Z-scheme composite was successfully synthe...Constructing a Z-scheme is a significant approach to improve the separation of photogene rated carriers for effective organic pollutant degradation.Herein,a BiVO4/ZnIn2S4(BZ) Z-scheme composite was successfully synthesized,and applied to photodegrade methyl orange(MO) irradiated by a LED lamp.Anchoring the BiVO4 on the ZnIn2S4 nanoparticles promoted the separation of photogenerated electronholes and broadened the light response range.The detailed characterizations,including surface morphology,elements valence state,and photocurrent performance,demonstrated that the enhanced separation of photogenerated carriers was the pivotal reason for the enhanced photocatalysis reaction.Benefiting from the excellent photocatalytic characteristics,the 5% mass ratio of BZ composite presented the highest MO degradation rate of 0.00997 min^-1,which was 1.9 and 10.3 times greater than the virgin ZnIn2S4 and BiVO4,respectively.Furthermore,the BZ hybrid materials indicated a well photo-stability in the four recycling tests.展开更多
In recent years,lanthanum-based nanomaterials(La-NMs)are selected as an efficient nano-adsorbent for phosphate removal because La3+has a strong affinity with oxygen-donor atoms from phosphate.Additionally,there are a ...In recent years,lanthanum-based nanomaterials(La-NMs)are selected as an efficient nano-adsorbent for phosphate removal because La3+has a strong affinity with oxygen-donor atoms from phosphate.Additionally,there are a broad interest and literature base for the effect of different synthesis optimization and environmental parameters on the adsorption performance of La-NMs.A considerable amount of research has also investigated the regeneration and application of La-NMs to real wastewater in a laboratory scale.Based on the literature survey,it was found that La-NMs are often produced via co-precipitation and hydrothermal methods.Moreover,phosphate’s adsorption process and behavior onto La-NMs are described well with the pseudo-second-order model and Langmuir model.The interaction mechanism between phosphate and La-NMs are dominated by ligand exchange,surface complexation and electrostatic attraction.Furthermore,phosphate could easily desorb from La-NMs due to the weak H-bonding interaction between phosphate and the H-bond acceptor groups on the surface of La-NMs.Despite the wealth of literature available in this area,there is a lack of systematic review to evaluate the gaps in the use of La-NMs to eliminate phosphate in water.In this review,we mainly summarize and discuss the role and the effect of the synthesis techniques on the physicochemical properties and the adsorption behavior of La-NMs.The possible adsorption mechanism,regeneration efficiency,and the application of La-NMs to the real environmental samples are also presented and highlighted.展开更多
Hydrogen peroxide(H_(2)O_(2))disproportionation,iron precipitation,and narrow pH range are the drawbacks of traditional Fenton process.To surmount these barriers,we proposed a ferric ion(Fe^(3+))-ascorbic acid(AA)comp...Hydrogen peroxide(H_(2)O_(2))disproportionation,iron precipitation,and narrow pH range are the drawbacks of traditional Fenton process.To surmount these barriers,we proposed a ferric ion(Fe^(3+))-ascorbic acid(AA)complex catalyzed calcium peroxide(CaO_(2))Fenton-like system to remove organic dyes in water.This collaborative Fe^(3+)/AA/CaO_(2)system presented an obvious improvement in the methyl orange(MO)decolorization,and also effectively eliminated other dyes.Response surface method was employed to optimize the running parameters for this coupling process.Under the optimized arguments(2.76 mmol/L Fe^(3+),0.68 mmol/L AA,and 4 mmol/L CaO_(2)),the MO removal achieved 98.90%after 15 min at pH 6.50,which was close to the computed outcome of 99.30%.Furthermore,this Fenton-like system could perform well in a wide range of pH(3-11),and enhance the H_(2)O_(2)decomposition and Fe ions recycle.The scavenger experiment result indicated that hydroxyl radical,superoxide anion free radical,and singlet oxygen were acted on the dye elimination.Moreover,electron spin resonance analysis corroborated that the existences of these active species in the Fe^(3+)/AA/CaO_(2)system.This study could advance the development of Fenton-like technique in organic effluent disposal.展开更多
The problem of water pollution has become increasingly serious,and it has already threatened the survival of mankind and has become an obstacle to the healthy development of human health.Here,we prepared a novel polyv...The problem of water pollution has become increasingly serious,and it has already threatened the survival of mankind and has become an obstacle to the healthy development of human health.Here,we prepared a novel polyvinyl alcohol(PVA)/polyacrylic acid(PAA)/MXene fiber membrane by electrospinning.After heat treatment of film and subsequent modification with Pd nanoparticles,PVA/PAA/MXene@PdNPs composite nanofiber membrane with high specific surface area and excellent catalytic performance was finally prepared.The uniform distribution of MXene sheets in the composite fiber membrane not only solves the problem that the MXene sheet is not easy to be monolayerized,but also can grow the self-reduced Pd nanoparticles on the MXene sheets.In addition,the composite nanofiber membrane exhibits excellent catalytic ability and cycle stability for 4-nitrophenol(4-NP)and 2-nitrophenol(2-NA),providing new strategy for the study of catalytic composite materials related to degradation of wastewater.展开更多
Molybdenum disulfide(MoS_(2))has excellent trapping ability for lead ions whereas its micro-/nanoscale size has greatly impeded its practical applications in the flow-through systems.Herein,a millimetersized nanocompo...Molybdenum disulfide(MoS_(2))has excellent trapping ability for lead ions whereas its micro-/nanoscale size has greatly impeded its practical applications in the flow-through systems.Herein,a millimetersized nanocomposite MoS_(2)-001 was synthesized for Pb^(2+)removal by loading MoS_(2) nanosheets into a polystyrene cation exchanger D-001 by a facile hydrothermal method.The proposed structure and adsorption mechanism of MoS_(2)-001 was confirmed by the scanning electron microscopy(SEM),transmission electron microscopy(TEM),X-ray diffraction(XRD),and X-ray photoelectron spectro scopy(XPS)analysis.The nanocomposite showed outstanding adsorption capacity and rapid adsorption kinetic for Pb^(2+)removal,and the adsorption behavior followed the Langmuir adsorption model and pseudo-firstmodel kinetic model.Pb^(2+)uptake by MoS_(2)-001 still maintains a high level even in the presence of extremely highly competitive ions(Ca(Ⅱ)and Mg(Ⅱ)),suggesting its high selectivity for Pb^(2+)adsorption.Besides,the fixed-bed column experiments further certified that MoS_(2)-001 is of great potential for Pb^(2+)removal from the wastewater in practical engineering applications.Even more gratifying is that the exhausted MoS_(2)-001 can be regenerated by NaCl-EDTANa_(2) solution without any significant adsorption capacity loss.Consequently,all the results indicated that MoS_(2)-001 is a promising candidate adsorbent for lead-containing wastewater treatment.展开更多
Ultrahigh pressure technique remarkably extends solid solubility limitation of Al alloying element(~25 at.%)in Mg alloys,resulting in unique solid-solution strengthening and age hardening response.Microhardness,yield ...Ultrahigh pressure technique remarkably extends solid solubility limitation of Al alloying element(~25 at.%)in Mg alloys,resulting in unique solid-solution strengthening and age hardening response.Microhardness,yield strength and ultimate compressive strength are improved simultaneously without degrading plasticity by forming homogeneous and globular-shaped Mg17Al12 precipitates of 10e30 nm.In addition,thermal resistance is enhanced by eliminating the dominant growth of(101)plane and anchoring dense stacking faults in phase interface.展开更多
Despite the development of various Lewis acidic nano-adsorbents for fluoride removal through innersphere coordination,strong competition for hydroxyl ions still hinders efficient water defluoridation.In addition,the c...Despite the development of various Lewis acidic nano-adsorbents for fluoride removal through innersphere coordination,strong competition for hydroxyl ions still hinders efficient water defluoridation.In addition,the critical issue of polysilicate scaling that results from the ubiquitous silicates must be addressed.To tackle these issues,an alternative approach to enhancing adsorption reactivity by modifying nano-adsorbents with dual Lewis and Bronsted acidity is proposed.The feasibility of this approach is demonstrated by growing zirconium phosphate(ZrP)inside a gel-type anion exchanger,N201,to produce nanocomposite ZrP@N201,in which the confined ZrP contained an otherwise metastable amorphous phase with Lewis acidic Zr^(4+) sites and Bronsted acidic monohydrogen phosphate groups(-O_(3)POH).Compared with the Lewis acidic nano-zirconium oxide analog(HZ0@N201),ZrP@N201 exhibited a greatly improved adsorption capacity(117.9 vs.52.3 mg/g-Zr)and mass transfer rate(3.56×10^(-6) vs.4.55×10^(-7) cm/s),while bulk ZrP produced a thermodynamically stableα-phase with Bronsted acidity that exhibited negligible adsorption capability toward fluoride.The enhanced defluoridation activity of ZrP@N201 is attributed to Bronsted acidity and the increased outer electron density of ZA+sites,as corroborated using XPS and solid-state NMR analysis.Moreover,Bronsted acidity strengthens the resistance of ZrP@N201 to silicate,allowing its full regeneration during cyclic defluoridation.Column tests demonstrated 3-10 times the amount of clean water from(waste)for ZrP@N201 as compared to both HZO@N201 and the widely used activated aluminum oxide.This study highlights the potential of developing nano-adsorbents with dual acidities for various environmental remediation applications.展开更多
基金NSFC(Nos.U22A20403,21301151 and 52070115)Natural Science Foundation of Hebei Province(Nos.B2021203036 and E2022203011)Key Project of the Hebei Education Department(No.ZD2021103).
文摘Polystyrene resins(PS)have been practical ion exchangers for radionuclides removal from water.However,nonspecific effects of ion exchange groups continue to be a major obstacle for emergency treatment with coexisting ions of high concentrations.The selectivity for Cs+enables zirconium phosphate(ZrP)to be the most promising inorganic sorbent for radioactive cesium extraction,despite being difficult to synthesize and causing excessive pressure loss in fixed-bed reactors due to fine powder.Herein,through facile confined crystallization in host macropores,we prepared PS confinedα-ZrP nanocrystalline(ZrP-PS).Size-screen sorption of layeredα-ZrP and sulfonic acid group preconcentration of PS synergistically enable a considerably higher Cs+affinity of ZrP-PS than PS,as confirmed by X-ray photoelectron spectroscopy(XPS)analysis.ZrP-PS demonstrated remarkable cesium sequestration performance in both batch and continuous experiments,with a high adsorption capacity of 269.58 mg/g,a rapid equilibrium within 80 min,and a continuous effluent volume of 2300 L/kg sorbents.Given the excellent selectivity for Cs+and flexibility to separate from treated water,ZrP-PS holds great promise as purification packages for the emergency treatment of radioactively contaminated water.
基金the supports from the National Natural Science Foundation of China(No.51908485)the Central Guidance on Local Science and Technology Development Fund of Hebei Province(No.226Z3603G)Hebei Province Foundation for Returnees(No.C20210502)。
文摘To surmount the obstacles of traditional Fenton method and synchronously utilize Cu^(2+)and polyphenol in water,an improved Fenton-like reaction applying calcium peroxide(CaO_(2))as H_(2)O_(2)source and regulating by the complex of Cu^(2+)-tartaric acid(TA,a representative of polyphenol)was constructed.A typical antibiotic,metronidazole(MTZ)could be effectively eliminated by the Cu^(2+)/TA/CaO_(2)system,and the optimized parameters were as follows:0.1 mmol/L Cu^(2+),2 mmol/L TA,2 mmol/L CaO_(2),and initial pH5.UV spectrum confirmed the formation of Cu^(2+)-TA complex,which promoted the Cu^(2+)/Cu+circulation through decreasing the Cu^(2+)/Cu^(+) couple redox potential,which further enhanced the H_(2)O_(2)decomposition and the formation of reactive species.Hydroxyl radical was dominant for MTZ degradation,followed by oxygen and superoxide radical.The degradation intermediates of MTZ were detected and their evolution way was speculated.Furthermore,the ternary process showed a wide p H tolerance(3–8)for removing MTZ and broad applicability for eliminating other dyes and antibiotics.This work provided a reference for Cu-based Fenton-like strategy for organic wastewater settlement.
基金financially supported by National Natural Science Foundation of China(Nos.U22A20403,22006047)Natural Science Foundation of Hebei Province(Nos.E2021203140,B2021203016)Hebei Industrial Innovation and Entrepreneurship team(No.215A7608D)。
文摘In some industrial wastewater,heavy metals combine with organic complexing agents to form heavy metal complexes(HMCs).These HMCs can be difficult to decompose and remove through conventional techniques due to their higher stability than free heavy metal ions.In recent years,persulfate based advanced oxidation processes(PS-based AOPs)have been recognized as a viable technique for HMCs degradation.Nevertheless,a comprehensive and in-depth understanding of the relevant HMCs decomplexation mechanisms in PS-based AOPs is still lacking.This review delineates the current progress of HMCs decomplexation in PS-based AOPs.We discuss the distinctions between the two widely used oxidant types in PS-based AOPs techniques.Moreover,we summarize and highlight the decomplexation mechanisms based on electron and energy transfer,and degradation pathways of HMCs.We also emphasize the effects of environmental water constituents,namely p H,inorganic ions,and natural organic matter(NOM),on HMCs decomplexation.Ultimately,we identify the existing challenges and perspectives that will steer the direction of advancing PS-based AOPs to remove HMCs.
基金This work was jointly supported by the National Natural Science Foundation of China with Granted No.62103451.
文摘The problem of triangular lattice formation in robot swarms has been investigated extensively in the literature,but the existing algorithms can hardly keep comparative performance from swarm simulation to real multi‐robot scenarios,due to the limited computation power or the restricted field of view(FOV)of robot sensors.Eventually,a distributed solution for triangular lattice formation in robot swarms with minimal sensing and computation is proposed and developed in this study.Each robot is equipped with a sensor with a limited FOV providing only a ternary digit of information about its neighbouring environment.At each time step,the motion command is directly determined by using only the ternary sensing result.The circular motions with a certain level of randomness lead the robot swarms to stable triangular lattice formation with high quality and robustness.Extensive numerical simulations and multi‐robot experiments are conducted.The results have demonstrated and validated the efficiency of the proposed approach.The minimised sensing and computation requirements pave the way for massive deployment at a low cost and implementation within swarms of miniature robots.
基金This work was financially supported by National Natural Science Foundation of China(Grant Nos.U22A20403,22006047)Natural Science Foundation of Hebei Province(E2021203140,B2021203016)Hebei Industrial Innovation and Entrepreneurship team(215A7608D).
文摘Amyloid nanofibrils(ANFs)are supramolecular polymers originally classified as pathological markers in various human degenerative diseases.However,in recent years,ANFs have garnered greater interest and are regarded as nature-based sustainable biomaterials in environmental science,material engineering,and nanotechnology.On a laboratory scale,ANFs can be produced from food proteins via protein unfolding,misfolding,and hydrolysis.Furthermore,ANFs have specific structural characteristics such as a high aspect ratio,good rigidity,chemical stability,and a controllable sequence.These properties make them a promising functional material in water decontamination research.As a result,the fabrication and application of ANFs and their composites in water purification have recently gained considerable attention.Despite the large amount of literature in this field,there is a lack of systematic review to assess the gap in using ANFs and their composites to remove contaminants from water.This review discusses significant advancements in design techniques as well as the physicochemical properties of ANFs-based composites.We also emphasize the current progress in using ANFs-based composites to remove inorganic,organic,and biological contaminants.The interaction mechanisms between ANFs-based composites and contaminants are also highlighted.Finally,we illustrate the challenges and opportunities associated with the future preparation and application of ANFs-based composites.We anticipate that this review will shed new light on the future design and use of ANFs-based composites.
基金supported by the National Natural Science Foundation of China(21872119)the Talent Engineering Training Funding Project of Hebei Province(A201905004)the Research Program of the College Science and Technology of Hebei Province(ZD2018091)。
基金financial supports from the National Natural Science Foundation of China(Nos.51908485 and 51608468)the China Postdoctoral Science Foundation(No.2019T120194)the University Science and Technology Program Project of Hebei Provincial Department of Education(No.QN2018258)。
文摘Constructing a Z-scheme is a significant approach to improve the separation of photogene rated carriers for effective organic pollutant degradation.Herein,a BiVO4/ZnIn2S4(BZ) Z-scheme composite was successfully synthesized,and applied to photodegrade methyl orange(MO) irradiated by a LED lamp.Anchoring the BiVO4 on the ZnIn2S4 nanoparticles promoted the separation of photogenerated electronholes and broadened the light response range.The detailed characterizations,including surface morphology,elements valence state,and photocurrent performance,demonstrated that the enhanced separation of photogenerated carriers was the pivotal reason for the enhanced photocatalysis reaction.Benefiting from the excellent photocatalytic characteristics,the 5% mass ratio of BZ composite presented the highest MO degradation rate of 0.00997 min^-1,which was 1.9 and 10.3 times greater than the virgin ZnIn2S4 and BiVO4,respectively.Furthermore,the BZ hybrid materials indicated a well photo-stability in the four recycling tests.
基金the financial support of the National Natural Science Foundation of China(NSFC)(No.21876145)Natural Science Foundation(NSF)of Hebei Province(No.B2018203331)+1 种基金the Support Program for the Top Young Talents of Hebei Province.the Supporting Plan for 100 Excellent Innovative Talents in Colleges and Universities of Hebei Province(No.SLRC2019041)。
文摘In recent years,lanthanum-based nanomaterials(La-NMs)are selected as an efficient nano-adsorbent for phosphate removal because La3+has a strong affinity with oxygen-donor atoms from phosphate.Additionally,there are a broad interest and literature base for the effect of different synthesis optimization and environmental parameters on the adsorption performance of La-NMs.A considerable amount of research has also investigated the regeneration and application of La-NMs to real wastewater in a laboratory scale.Based on the literature survey,it was found that La-NMs are often produced via co-precipitation and hydrothermal methods.Moreover,phosphate’s adsorption process and behavior onto La-NMs are described well with the pseudo-second-order model and Langmuir model.The interaction mechanism between phosphate and La-NMs are dominated by ligand exchange,surface complexation and electrostatic attraction.Furthermore,phosphate could easily desorb from La-NMs due to the weak H-bonding interaction between phosphate and the H-bond acceptor groups on the surface of La-NMs.Despite the wealth of literature available in this area,there is a lack of systematic review to evaluate the gaps in the use of La-NMs to eliminate phosphate in water.In this review,we mainly summarize and discuss the role and the effect of the synthesis techniques on the physicochemical properties and the adsorption behavior of La-NMs.The possible adsorption mechanism,regeneration efficiency,and the application of La-NMs to the real environmental samples are also presented and highlighted.
基金the financial support from the Natural Science Foundation of China(No.51908485)the Natural Science Foundation of Hebei province(Nos.E2020203185,B2020203033,B2018203331)the University Science and Technology Program Project of Hebei Provincial Department of Education(No.QN2020143).
文摘Hydrogen peroxide(H_(2)O_(2))disproportionation,iron precipitation,and narrow pH range are the drawbacks of traditional Fenton process.To surmount these barriers,we proposed a ferric ion(Fe^(3+))-ascorbic acid(AA)complex catalyzed calcium peroxide(CaO_(2))Fenton-like system to remove organic dyes in water.This collaborative Fe^(3+)/AA/CaO_(2)system presented an obvious improvement in the methyl orange(MO)decolorization,and also effectively eliminated other dyes.Response surface method was employed to optimize the running parameters for this coupling process.Under the optimized arguments(2.76 mmol/L Fe^(3+),0.68 mmol/L AA,and 4 mmol/L CaO_(2)),the MO removal achieved 98.90%after 15 min at pH 6.50,which was close to the computed outcome of 99.30%.Furthermore,this Fenton-like system could perform well in a wide range of pH(3-11),and enhance the H_(2)O_(2)decomposition and Fe ions recycle.The scavenger experiment result indicated that hydroxyl radical,superoxide anion free radical,and singlet oxygen were acted on the dye elimination.Moreover,electron spin resonance analysis corroborated that the existences of these active species in the Fe^(3+)/AA/CaO_(2)system.This study could advance the development of Fenton-like technique in organic effluent disposal.
基金the financial supports of the National Natural Science Foundation of China(No.21872119)Support Program for the Top Young Talents of Hebei Province+1 种基金China Postdoctoral Science Foundation(No.2015M580214)Research Program of the College Science&Technology of Hebei Province(No.ZD2018091)。
文摘The problem of water pollution has become increasingly serious,and it has already threatened the survival of mankind and has become an obstacle to the healthy development of human health.Here,we prepared a novel polyvinyl alcohol(PVA)/polyacrylic acid(PAA)/MXene fiber membrane by electrospinning.After heat treatment of film and subsequent modification with Pd nanoparticles,PVA/PAA/MXene@PdNPs composite nanofiber membrane with high specific surface area and excellent catalytic performance was finally prepared.The uniform distribution of MXene sheets in the composite fiber membrane not only solves the problem that the MXene sheet is not easy to be monolayerized,but also can grow the self-reduced Pd nanoparticles on the MXene sheets.In addition,the composite nanofiber membrane exhibits excellent catalytic ability and cycle stability for 4-nitrophenol(4-NP)and 2-nitrophenol(2-NA),providing new strategy for the study of catalytic composite materials related to degradation of wastewater.
基金the financial support from the National Key Research and Development Program of China(No.2017YFE0107200)Postgraduate Research&Practice Innovation Program of Jiangsu Province(No.KYCX20_1105)+2 种基金NSFC(No.21876145)the Supporting Plan for 100 Excellent Innovative Talents in Colleges and Universities of Hebei Province(No.SLRC2019041)Open Foundation of State Key Laboratory of Pollution Control and Resource Reuse(No.PCRRF18026,Nanjing University)。
文摘Molybdenum disulfide(MoS_(2))has excellent trapping ability for lead ions whereas its micro-/nanoscale size has greatly impeded its practical applications in the flow-through systems.Herein,a millimetersized nanocomposite MoS_(2)-001 was synthesized for Pb^(2+)removal by loading MoS_(2) nanosheets into a polystyrene cation exchanger D-001 by a facile hydrothermal method.The proposed structure and adsorption mechanism of MoS_(2)-001 was confirmed by the scanning electron microscopy(SEM),transmission electron microscopy(TEM),X-ray diffraction(XRD),and X-ray photoelectron spectro scopy(XPS)analysis.The nanocomposite showed outstanding adsorption capacity and rapid adsorption kinetic for Pb^(2+)removal,and the adsorption behavior followed the Langmuir adsorption model and pseudo-firstmodel kinetic model.Pb^(2+)uptake by MoS_(2)-001 still maintains a high level even in the presence of extremely highly competitive ions(Ca(Ⅱ)and Mg(Ⅱ)),suggesting its high selectivity for Pb^(2+)adsorption.Besides,the fixed-bed column experiments further certified that MoS_(2)-001 is of great potential for Pb^(2+)removal from the wastewater in practical engineering applications.Even more gratifying is that the exhausted MoS_(2)-001 can be regenerated by NaCl-EDTANa_(2) solution without any significant adsorption capacity loss.Consequently,all the results indicated that MoS_(2)-001 is a promising candidate adsorbent for lead-containing wastewater treatment.
基金We greatly acknowledge the financial support from NSFC(no.51771162,51422105)National Key Research and Development Program(2017YFB0702001)Distinguished Youth Foundation of Hebei Province(E2015203404).
文摘Ultrahigh pressure technique remarkably extends solid solubility limitation of Al alloying element(~25 at.%)in Mg alloys,resulting in unique solid-solution strengthening and age hardening response.Microhardness,yield strength and ultimate compressive strength are improved simultaneously without degrading plasticity by forming homogeneous and globular-shaped Mg17Al12 precipitates of 10e30 nm.In addition,thermal resistance is enhanced by eliminating the dominant growth of(101)plane and anchoring dense stacking faults in phase interface.
基金We greatly appreciate the financial support from the National Key Research and Development Program of China(No.2022YFC3205300)the National Natural Science Foundation of China(No.22122604).
文摘Despite the development of various Lewis acidic nano-adsorbents for fluoride removal through innersphere coordination,strong competition for hydroxyl ions still hinders efficient water defluoridation.In addition,the critical issue of polysilicate scaling that results from the ubiquitous silicates must be addressed.To tackle these issues,an alternative approach to enhancing adsorption reactivity by modifying nano-adsorbents with dual Lewis and Bronsted acidity is proposed.The feasibility of this approach is demonstrated by growing zirconium phosphate(ZrP)inside a gel-type anion exchanger,N201,to produce nanocomposite ZrP@N201,in which the confined ZrP contained an otherwise metastable amorphous phase with Lewis acidic Zr^(4+) sites and Bronsted acidic monohydrogen phosphate groups(-O_(3)POH).Compared with the Lewis acidic nano-zirconium oxide analog(HZ0@N201),ZrP@N201 exhibited a greatly improved adsorption capacity(117.9 vs.52.3 mg/g-Zr)and mass transfer rate(3.56×10^(-6) vs.4.55×10^(-7) cm/s),while bulk ZrP produced a thermodynamically stableα-phase with Bronsted acidity that exhibited negligible adsorption capability toward fluoride.The enhanced defluoridation activity of ZrP@N201 is attributed to Bronsted acidity and the increased outer electron density of ZA+sites,as corroborated using XPS and solid-state NMR analysis.Moreover,Bronsted acidity strengthens the resistance of ZrP@N201 to silicate,allowing its full regeneration during cyclic defluoridation.Column tests demonstrated 3-10 times the amount of clean water from(waste)for ZrP@N201 as compared to both HZO@N201 and the widely used activated aluminum oxide.This study highlights the potential of developing nano-adsorbents with dual acidities for various environmental remediation applications.
