In this work,we constructed a three-dimensional electrochemical system(3D-ECO),which included the cathode and anode electrode plates,as well as the screening of three-dimensional particle electrodes and parameter opti...In this work,we constructed a three-dimensional electrochemical system(3D-ECO),which included the cathode and anode electrode plates,as well as the screening of three-dimensional particle electrodes and parameter opti-mization,for the degradation of landfill leachate(LL)containing elevated levels of tetracycline(TC),and explored its mechanism of action.Firstly,titanium-based ruthenium-iridium(Ti/RuO_(2)-IrO_(2)),titanium-based ruthenium-iridium-platinum(Ti/Pt-RuO_(2)-IrO_(2)),and titanium-based tin-antimony(Ti/SnO_(2)-Sb_(2)O_(3))were employed as an-odes in the electrocatalytic oxidation system,with titanium and stainless steel plates serving as cathodes,to construct the optimal two-dimensional electrocatalytic oxidation system(2D-ECO)through cross-comparison ex-periments.Subsequently,using granular activated carbon(GAC),coconut shell biochar(CBC),walnut shell carbon(WBC),and bamboo charcoal(BBC)as particle electrodes,a 3D-ECO system was developed.The influence of var-ious operational parameters on treating TC-containing LL was investigated.The optimal operating parameters obtained from the study was:pH=5,current density of 30 mA/cm^(2),particle dosage of 7 g/L,particle size ranging from 1.70 to 2.00 mm,and electrode spacing of 4 cm.Under these conditions,the COD removal rate of 3D-ECO within three hours was 90.25%,the TC removal rate was 72.41%,and the NH_(3)-N removal rate was 39.52%.The removal of TC followed a pseudo-first-order kinetic model.Additionally,degradation mechanisms were elucidated through electron paramagnetic resonance(EPR)spectrometer and Tert-Butanol(TBA)quenching experiments,indicating that the degradation primarily occurred through a non-radical(1O_(2))pathway.This re-search offers a comprehensive analysis of the simultaneous breakdown of intricate LL matrices and TC,enhancing our comprehension of the degradation processes and underlying mechanisms.展开更多
To mitigate the impact of interdiffusion reactions between the silicide slurry and Ta12W alloy substrate during vacuum sintering process on the oxidation resistance of the silicide coating,a micro-arc oxidation pretre...To mitigate the impact of interdiffusion reactions between the silicide slurry and Ta12W alloy substrate during vacuum sintering process on the oxidation resistance of the silicide coating,a micro-arc oxidation pretreatment was employed to construct a Ta_(2)O_(5)ceramic layer on the Ta12W alloy surface.Subsequently,a slurry spraying-vacuum sintering method was used to prepare a Si-Cr-Ti-Zr coating on the pretreated substrate.Comparative studies were conducted on the microstructure,phase composition,and isothermal oxidation resistance(at 1600℃)of the as-prepared coatings with and without the micro-arc oxidation ceramic layer.The results show that the Ta_(2)O_(5)layer prepared at 400 V is more continuous and has smaller pores than that prepared at 350 V.After microarc oxidation pretreatment,the Si-Cr-Ti-Zr coating on Ta12W alloy consists of three distinct layers:an upper layer dominated by Ti_(5)Si_(3),Ta_(5)Si_(3),and ZrSi;a middle layer dominated by TaSi_(2);a coating/substrate interfacial reaction layer dominated by Ta_(5)Si_(3).Both the Si-Cr-Ti-Zr coatings with and without the Ta_(2)O_(5)ceramic layer do not fail after isothermal oxidation at 1600℃for 5 h.Notably,the addition of the Ta2O5 ceramic layer reduces the high-temperature oxidation rate of the coating.展开更多
In this study,a novel polysaccharide GPA-G 2-H was derived from ginseng.Furthermore,the coherent study of its structural characteristics,fermented characteristics in vitro,as well as antioxidant mechanism of fermented...In this study,a novel polysaccharide GPA-G 2-H was derived from ginseng.Furthermore,the coherent study of its structural characteristics,fermented characteristics in vitro,as well as antioxidant mechanism of fermented product FGPA-G 2-H on Aβ25-35-induced PC 12 cells were explored.The structure of GPA-G 2-H was determined by means of zeta potential analysis,FTIR,HPLC,XRD,GC-MS and NMR.The backbone of GPA-G 2-H was mainly composed of→4)-α-D-Glcp-(1→with branches substituted at O-3.Notably,GPA-G 2-H was degraded by intestinal microbiota in vitro with total sugar content and pH value decreasing,and short-chain fatty acids(SCFAs)increasing.Moreover,GPA-G 2-H significantly promoted the proliferation of Lactobacillus,Muribaculaceae and Weissella,thereby making positive alterations in intestinal microbiota composition.Additionally,FGPA-G 2-H activated the Nrf 2/HO-1 signaling pathway,enhanced HO-1,NQO 1,SOD and GSH-Px,while inhabited Keap 1,MDA and LDH,which alleviated Aβ-induced oxidative stress in PC 12 cells.These provide a solid theoretical basis for the further development of ginseng polysaccharides as functional food and antioxidant drugs.展开更多
Fine-grained nuclear graphite is a key material in high-temperature gas-cooled reactors(HTGRs).During air ingress accidents,core graphite components undergo severe oxidation,threatening structural integrity.Therefore,...Fine-grained nuclear graphite is a key material in high-temperature gas-cooled reactors(HTGRs).During air ingress accidents,core graphite components undergo severe oxidation,threatening structural integrity.Therefore,understanding the oxidation behavior of nuclear graphite is essential for reactor safety.The influence of oxidation involves multiple factors,including temperature,sample size,oxidant,impurities,filler type and size,etc.The size of the filler particles plays a crucial role in this study.Five ultrafine-and superfine-grained nuclear graphite samples(5.9-34.4μm)are manufactured using identical raw materials and manufacturing processes.Isothermal oxidation tests conducted at 650℃-750℃ are used to study the oxidation behavior.Additionally,comprehensive characterization is performed to analyze the crystal structure,surface morphology,and nanoscale to microscale pore structure of the samples.Results indicate that oxidation behavior cannot be predicted solely based on filler grain size.Reactive site concentration,characterized by active surface area,dominates the chemical reaction kinetics,whereas pore tortuosity,quantified by the structural parameterΨ,plays a key role in regulating oxidant diffusion.These findings clarify the dual role of microstructure in oxidation mechanisms and establish a theoretical and experimental basis for the design of high-performance nuclear graphite capable of long-term service in high-temperature gas-cooled reactors.展开更多
Traumatic brain injury involves complex pathophysiological mechanisms,among which oxidative stress significantly contributes to the occurrence of secondary injury.In this study,we evaluated hypidone hydrochloride(YL-0...Traumatic brain injury involves complex pathophysiological mechanisms,among which oxidative stress significantly contributes to the occurrence of secondary injury.In this study,we evaluated hypidone hydrochloride(YL-0919),a self-developed antidepressant with selective sigma-1 receptor agonist properties,and its associated mechanisms and targets in traumatic brain injury.Behavioral experiments to assess functional deficits were followed by assessment of neuronal damage through histological analyses and examination of blood-brain barrier permeability and brain edema.Next,we investigated the antioxidative effects of YL-0919 by assessing the levels of traditional markers of oxidative stress in vivo in mice and in vitro in HT22 cells.Finally,the targeted action of YL-0919 was verified by employing a sigma-1 receptor antagonist(BD-1047).Our findings demonstrated that YL-0919 markedly improved deficits in motor function and spatial cognition on day 3 post traumatic brain injury,while also decreasing neuronal mortality and reversing blood-brain barrier disruption and brain edema.Furthermore,YL-0919 effectively combated oxidative stress both in vivo and in vitro.The protective effects of YL-0919 were partially inhibited by BD-1047.These results indicated that YL-0919 relieved impairments in motor and spatial cognition by restraining oxidative stress,a neuroprotective effect that was partially reversed by the sigma-1 receptor antagonist BD-1047.YL-0919 may have potential as a new treatment for traumatic brain injury.展开更多
TiB_(2)coatings can significantly enhance the high-temperature oxidation resistance of molybdenum,which would broaden the application range of molybdenum and alloys thereof.However,traditional methods for preparing Ti...TiB_(2)coatings can significantly enhance the high-temperature oxidation resistance of molybdenum,which would broaden the application range of molybdenum and alloys thereof.However,traditional methods for preparing TiB_(2)coatings have disadvantages such as high equipment costs,complicated processes,and highly toxic gas emissions.This paper proposes an environmentally friendly method,which requires inexpensive equipment and simple processing,for preparing TiB_(2)coating on molybdenum via electrophoretic deposition within Na3AlF6-based molten salts.The produced TiB_(2)layer had an approximate thickness of 60μm and exhibited high density,outstanding hardness(38.2 GPa)and robust adhesion strength(51 N).Additionally,high-temperature oxidation experiments revealed that,at900℃,the TiB_(2)coating provided effective protection to the molybdenum substrate against oxidation for 3 h.This result indicates that the TiB_(2)coating prepared on molybdenum using molten salt electrophoretic deposition possesses good high-temperature oxidation resistance.展开更多
Nano-zinc oxides(ZnO)demonstrate remarkable antibacterial properties.To further enhance the corrosion resistance and antibacterial efficiency of magnesium alloy micro-arc oxidation(MAO)coatings,this study investigates...Nano-zinc oxides(ZnO)demonstrate remarkable antibacterial properties.To further enhance the corrosion resistance and antibacterial efficiency of magnesium alloy micro-arc oxidation(MAO)coatings,this study investigates the preparation of ZnO-containing micro-arc oxidation coatings with dual functionality by incorporating nano-ZnO into MAO electrolyte.The influence of varying ZnO concentrations on the microstructure,corrosion resistance,and antibacterial properties of the coating was examined through microstructure analysis,immersion tests,electrochemical experiments,and antibacterial assays.The findings revealed that the addition of nano-ZnO significantly enhanced the corrosion resistance of the MAO-coated alloy.Specifically,when the ZnO concentration in the electrolyte was 5 g/L,the corrosion rate was more than ten times lower compared to the MAO coatings without ZnO.Moreover,the antibacterial efficacy of ZnO+MAO coating,prepared with a ZnO concentration of 5 g/L,surpassed 95%after 24 h of co-culturing with Staphylococcus aureus(S.aureus).The nano-ZnO+MAO-coated alloy exhibited exceptional degradation resistance,corrosion resistance,and antibacterial effectiveness.展开更多
Water splitting hinges crucially on the availability of electrocatalysts for the oxygen evolution reaction.The surface reconstruction has been widely observed in perovskite catalysts,and the reconstruction degree has ...Water splitting hinges crucially on the availability of electrocatalysts for the oxygen evolution reaction.The surface reconstruction has been widely observed in perovskite catalysts,and the reconstruction degree has been often correlated with the activity enhancement.Here,a systematic study on the roles of Fe substitution in activation of perovskite LaNiO_(3)is reported.The substituting Fe content influences both current change tendency and surface reconstruction degree.LaNi_(0.9)Fe_(0.1)O_(3)is found exhibiting a volcano-peak intrinsic activity in both pristine and reconstructed among all substituted perovskites in the LaNi_(1-x)Fe_(x)O_(3)(x=0.00,0.10,0.25,0.50,0.75,1.00)series.The reconstructed LaNi_(0.9)Fe_(0.1)O_(3)shows a higher intrinsic activity than most reported NiFe-based catalysts.Besides,density functional theory calculations reveal that Fe substitution can lower the O 2p level,which thus stabilize lattice oxygen in LaNi0.9Fe0.1O3 and ensure its long-term stability.Furthermore,it is vital interesting that activity of the reconstructed catalysts relied more on the surface chemistry rather than the reconstruction degree.The effect of Fe on the degree of surface reconstruction of the perovskite is decoupled from that on its activity enhancement after surface reconstruction.This finding showcases the importance to customize the surface chemistry of reconstructed catalysts for water oxidation.展开更多
Some active metal oxides(Al_(2)O_(3),TiO_(2),and Cr_(2)O_(3))were selected as dopants to the Al_(2)O_(3)-based ceramic shells for investment casting of K417G superalloy.The effects of dopant types and contents(0,2,5,a...Some active metal oxides(Al_(2)O_(3),TiO_(2),and Cr_(2)O_(3))were selected as dopants to the Al_(2)O_(3)-based ceramic shells for investment casting of K417G superalloy.The effects of dopant types and contents(0,2,5,and 8 wt.%)on the wettability and interfacial reaction between the alloy and shell were investigated by a sessile-drop experiment.The results show that increasing the Al_(2)O_(3) doping contents(0−8 wt.%)reduces the porosity(21.74%−10.08%)and roughness(3.22−1.34μm)of the shell surface.The increase in Cr_(2)O_(3) dopant content(2−8 wt.%)further exacerbates the interfacial reaction,leading to an increase in the thickness of the reaction layer(2.6−3.1μm)and a decrease in the wetting angle(93.9°−91.0°).The addition of Al_(2)O_(3) and TiO_(2) dopants leads to the formation of Al_(2)TiO_(5) composite oxides in the reaction products,which effectively inhibits the interfacial reaction.The increase in TiO_(2) dopant contents(0−8 wt.%)further promotes the formation of Al_(2)TiO_(5),which decreases the thickness of the interfacial reaction layer(3.9−1.2μm)and increases the wetting angle(95.0°−103.8°).The introduced dopants enhance the packing density of the shell surface,while simultaneously suppress the diffusion of active metal elements from the alloy matrix to the interface.展开更多
Investigating structural and hydroxyl group effects in electrooxidation of alcohols to value-added products by solid-acid electrocatalysts is essential for upgrading biomass alcohols.Herein,we report efficient electro...Investigating structural and hydroxyl group effects in electrooxidation of alcohols to value-added products by solid-acid electrocatalysts is essential for upgrading biomass alcohols.Herein,we report efficient electrocatalytic oxidations of saturated alcohols(C_(1)-C_(6))to selectively form formate using Ni Co hydroxide(Ni Co-OH)derived Ni Co_(2)O_(4)solid-acid electrocatalysts with balanced Lewis acid(LASs)and Brønsted acid sites(BASs).Thermal treatment transforms BASs-rich(89.6%)Ni Co-OH into Ni Co_(2)O_(4)with nearly equal distribution of LASs(53.1%)and BASs(46.9%)which synergistically promote adsorption and activation of OH-and alcohol molecules for enhanced oxidation activity.In contrast,BASs-enriched Ni Co-OH facilitates formation of higher valence metal sites,beneficial for water oxidation.The combined experimental studies and theoretical calculation imply the oxidation ability of C1-C6alcohols increases as increased number of hydroxyl groups and decreased HOMO-LUMO gaps:methanol(C_(1))<ethylene glycol(C_(2))<glycerol(C3)<meso-erythritol(C4)<xylitol(C5)<sorbitol(C6),while the formate selectivity shows the opposite trend from 100 to 80%.This study unveils synergistic roles of LASs and BASs,as well as hydroxyl group effect in electro-upgrading of alcohols using solid-acid electrocatalysts.展开更多
The oxidation behavior of Ti55 alloy and TiBw/Ti55 composites at temperatures ranging from 960 to 1000℃ was investigated by characterizing the surface and cross-section microstructure of specimens.Results showed that...The oxidation behavior of Ti55 alloy and TiBw/Ti55 composites at temperatures ranging from 960 to 1000℃ was investigated by characterizing the surface and cross-section microstructure of specimens.Results showed that TiBw reinforcement accelerated the occurrence of Ti_(6O)/Ti_(3O) by dissolving oxygen in titanium in the starting oxidation stage,and the Ti_(6O)/Ti_(3O) transformed into TiO_(2) with the progression of oxidation.Meanwhile,TiBw reinforcement promoted the formation of(101)crystal planes to be beneficial to the growth of TiO_(2) twins.The cross-sectional characterization showed that the oxide layer of Ti55 alloy and TiBw/Ti55 composites from outside to inside was TiO_(2)+Al_(2)O_(3),TiO_(2),Ti-Sn compounds,Ti_(6O)/Ti_(3O) in sequence,which was confirmed by calculating the standard Gibbs free energy of the oxide nucleation.The TiBw reinforcement accelerated the occurrence of suboxides Ti_(6O)/Ti_(3O) by dissolving oxygen in titanium,and promoted the formation of(101)crystal planes which were beneficial to the growth of TiO_(2) twins.The optimal addition of TiBw induced the TiO_(2) twins,promoted the random orientation of oxides and refined the oxide size of the TiBw/Ti55 composites with 3.5%volume fractions of TiBw,resulting in the best resistance against oxidation.展开更多
The synergistic effect of Se with Fe can enhance the catalytic activities of the system for oxidation reactions.Based on this principle,a series of Se/Fe materials have been invented to develop the heterogeneous catal...The synergistic effect of Se with Fe can enhance the catalytic activities of the system for oxidation reactions.Based on this principle,a series of Se/Fe materials have been invented to develop the heterogeneous catalysts with industrial application potential.However,the present methods suffer from the tedious procedures,the high reaction temperature,and the low synthetic efficiency.In this paper,we report the synthesis of Se/Fe materials just by precipitating Fe(NO_(3))_(3)with the in situ prepared aqueous NaSe/NaSeO_(3)under mild conditions.The concise method may resolve the issues hindering the large-scale applications of Se/Fe materials.展开更多
A novel tetra-europium(III)-containing antimonotungstate,Na_(8.2)[H_(2)N(CH_(3))_(2)]_(9)[Na_(10.8)(tar)_(4)(H_(2)O)_(20)(Eu_(2)Sb_(2)W_(21)O_(72))_(2)]·44.5H_(2)O(EuSbW,H_(4)tar=dl-tartaric acid),has been synthe...A novel tetra-europium(III)-containing antimonotungstate,Na_(8.2)[H_(2)N(CH_(3))_(2)]_(9)[Na_(10.8)(tar)_(4)(H_(2)O)_(20)(Eu_(2)Sb_(2)W_(21)O_(72))_(2)]·44.5H_(2)O(EuSbW,H_(4)tar=dl-tartaric acid),has been synthesized and characterized.The dimeric polyoxoanion of EuSbW consists of two Dawson-like{Eu_(2)Sb_(2)W_(21)}units bridged by four dl-tartaric acid ligands.The adjacent carboxyl and hydroxy groups in each tartaric acid simultaneously chelate with W and Eu atoms from different{Eu_(2)Sb_(2)W_(21)}units,thereby forming the dimeric structure.EuSbW represents an extremely rare polyoxometalate where four tartaric acid ligands function as connectors to bridge two{Eu_(2)Sb_(2)W_(21)}units.Additionally,EuSbW exhibits excellent catalytic activity and reusability in the oxidation of thioethers and alcohols,achieving 100%conversion and>99%selectivity for various thioethers,and 85–100%conversion with 90–99%selectivity for diverse alcohols under mild conditions.展开更多
Enhancing the activity of photocatalysts is a critical challenge for improving the photocatalytic degradation of contaminated wastewater.Here,a novel Ce single-atom-doped titanate nanotube photocatalyst(CeH_(2)Ti_(2)O...Enhancing the activity of photocatalysts is a critical challenge for improving the photocatalytic degradation of contaminated wastewater.Here,a novel Ce single-atom-doped titanate nanotube photocatalyst(CeH_(2)Ti_(2)O_(5)·H_(2)O)was successfully synthesized using a onepot solvothermal method.Degradation experiments revealed that the optimal Ce doping ratio was 1.0%.The ultraviolet-visible diffuse reflectance spectroscopy results showed that the bandgap of the Ce-doped sample decreased from 3.02 to 2.87 eV,enhancing the absorption in the visible spectral range.At the same time,the BrunauerEmmett-Teller specific surface area increased from 63.68 to 88.95 m^(2)g^(-1).The 1.0%Ce-H_(2)Ti_(2)O_(5)·H_(2)O(HTC_(1))could degrade 99.04%of 100 mg L-1rhodamine B(RhB)after 40 min of visible-light irradiation.The degradation efficiency decreased by only 21.24%after five cycles.The results of free-radical quenching and electron spin resonance spectroscopy analyses indicated that HTC_(1)achieved efficient degradation of RhB through a direct hole oxidation mechanism.Compared with pure protonated titanate nanotubes(H_(2)Ti_(2)O_(5)·H_(2)O),HTC_(1)had a higher specific surface area,more electron traps,narrower bandgap,longer hole lifetime,and suppressed photogenerated charge recombination rate owing to the Ce single-atom doping.展开更多
Coupling adsorption and in-situ Fenton-like oxidation process was developed for Methylene blue(MB) using refined iron-containing lowgrade attapulgite(ATP) clay, and the removal mechanism was investigated. The MB was i...Coupling adsorption and in-situ Fenton-like oxidation process was developed for Methylene blue(MB) using refined iron-containing lowgrade attapulgite(ATP) clay, and the removal mechanism was investigated. The MB was initially adsorbed on the porous ATPs, and then the enriched MB was removed by the H2O2-assisted Fenton-like oxidation with the iron-containing ATP catalyst. Under optimal conditions, the ATP powder exhibits the maximum removal efficiency of 100% with negligible iron leaching(1.5 mg L^(-1)) and no sludge formation. Furthermore,polysulfone/ATP(PSF/ATP) pellets were fabricated through a water-induced phase separation process to construct a fixed-bed reactor(FBR) for continuous contaminant removal. For the first cycle, the maximum adsorption capacity was 15.5 L with an outlet MB concentration of1.973 mg L-1(< 2 mg L^(-1), GB4287-2012) using the PSF/ATP pellets containing 50.0 g of ATP powders, and the maximum Fenton-like oxidation capacity was 35.5 L with the outlet concentration of 0.831 mg L^(-1). After five cycles, the total treated volume of the MB solution was ca. 255 L, and the efficiency remained above 99%. After 10 h of continuous treatment towards practical resin industrial wastewater, the chemical oxygen demand(COD) removal efficiency was still measured at 83.05%, costing 0.398 $ m^(-3). These results demonstrate the practical applicability of iron-containing low-grade ATP clay for textile water treatment.展开更多
Press hardening with manganese-boron steels is a prominent manufacturing technique that allows for reduced weight and expense in automotive construction,while providing enhanced crash performance.Nevertheless,the deve...Press hardening with manganese-boron steels is a prominent manufacturing technique that allows for reduced weight and expense in automotive construction,while providing enhanced crash performance.Nevertheless,the development of a loosely attached oxide layer during press hardening and following additional processing of the layer presents a significant risk to the dimensional precision of the completed product.Here,we develop a new preprocessing approach to address the scale spallation issue by introducing trace amounts of silicate and tungstate into the rinsing solution following pickling.We demonstrate that the pre-deposited membrane promotes the formation of a noticeably thinner,more continuous and stickier oxide scale at high temperatures,enabling the direct application of automobile painting onto the scale.Our research provides an economical remedy to the troublesome scale flaking issue without requiring any modifications to the existing production line,and conveys a thorough comprehension of the mechanism by which the preprocessed membrane resists high-temperature oxidation.展开更多
Photocatalytic activation of C-H bonds is versatile but challenging for undergoing oriented conversion processes.Herein,a spatially site-isolated heterojunction(ZS-Vs/ZIS)of ZnIn2S4 with strong Lewis acidity(ZIS)and Z...Photocatalytic activation of C-H bonds is versatile but challenging for undergoing oriented conversion processes.Herein,a spatially site-isolated heterojunction(ZS-Vs/ZIS)of ZnIn2S4 with strong Lewis acidity(ZIS)and ZnS with S-vacancy(ZS-Vs)is constructed for activating α-C‒H bond and forming·O_(2)^(-)to cleave the C-H bond,respectively.ZS-Vs/ZIS displays outstanding performance in visible-light partial photooxidation of bio-based 5-hydroxymethylfurfural(HMF)to 2,5-diformylfuran(DFF)in an unprecedented yield of 95.7%at 25°C.In-situ experiments and calculations reveal that Zn sites of ZIS serve as hole enrichment to adsorb HMF for α-C‒H activation via ligand-to-metal charge transfer.Shallow trap states introduced by S-vacancy in ZS-Vs act as an electron pool to realize directed O_(2) activation into·O_(2)^(-)for breaking pre-activated α-C‒H bond in HMF to exclusively give DFF.Moreover,ZS-Vs/ZIS has good recyclability and universality in the photooxidation of various alcohols to carbonyls(86.4-95.6%yields).The synergistic C-H activation/breaking strategy exhibits high potential in targeted photocatalytic transformations.展开更多
Different reactive flame retardants have been extensively developed for vinyl ester resins(VERs),but very few of them can yield a flame-retardant resin that meets defined standards(e.g.UL-94 V-0 rating).In this work,p...Different reactive flame retardants have been extensively developed for vinyl ester resins(VERs),but very few of them can yield a flame-retardant resin that meets defined standards(e.g.UL-94 V-0 rating).In this work,phosphorous-containing 1-vinylimidazole salts(called VIDHP and VIDPP)were synthesized through the facile neutralization of the acid and 1-vinylimidazole.VIDHP and VIDPP were then applied as flame-retardant crosslinking agents of VERs,by which phosphorus-containing groups could be incorporated into the resin chain via ionic bonds.VIDHP/VER and VIDPP/VER showed a high curing activity and can be well cured in moderate temperatures.With 20 wt.%additions of VIDHP and VIDPP,VIDHP20/VER,and VIDPP20/VER presented a limiting oxygen index value of 29.7%and 28.4%,respectively,with the latter achieving a UL 94 V0 rating.In the cone calorimetric test,compared to the unmodified VERs,VIDPP20/VER exhibited large reductions in the peak heat release rate,total heat release rate,and total smoke release rate while VIDHP20/VER demonstrated comparatively inferior performance in terms of the heat release.VIDHP20/VER and VIDPP20/VER showed good thermal stability and presented a little lower glass transition temperature than the control sample.VIDPP with a low phosphorus oxidation state(+1)demonstrated high flame-retardant activities in the gaseous phase,whereas VIDHP with a high phosphorus oxidation state(+5)primarily exhibited efficacy in the condensed phase.展开更多
The widespread occurrence of antibiotics in wastewater aroused serious attention.UV-based advanced oxidation processes(UV-AOPs)are powerful technologies in removing antibiotics in wastewater,which include UV/catalyst,...The widespread occurrence of antibiotics in wastewater aroused serious attention.UV-based advanced oxidation processes(UV-AOPs)are powerful technologies in removing antibiotics in wastewater,which include UV/catalyst,UV/H_(2)O_(2),UV/Fenton,UV/persulfate,UV/chlorine,UV/ozone,and UV/peracetic acid.In this review,we collated recent advances in application of UV-AOPs for the abatement of fiuoroquinolones(FQs)as widely used class of antibiotics.Representative FQs of ciprofioxacin,norfioxacin,ofioxacin,and enrofioxacin were most extensively studied in the state-of-art studies.The evolvement of gas-state and solid-state UV light sources was presented and batch and continuous fiow UV reactors were compared towards practical applications in UV-AOPs.Generally,degradation of FQs followed the pseudo-first order kinetics in UV-AOPs and strongly affected by the operating factors and components of water matrix.Participation of reactive species and transformation mechanisms of FQs were compared among different UV-AOPs.Challenges and future prospects were pointed out for providing insights into the practical application of UV-AOPs for antibiotic remediation in wastewater.展开更多
Active and poisoning-resistant Ru-based electrocatalysts for the hydrogen oxidation reaction(HOR)are designed and fabricated by integrating Cu/Ru dual single atoms and alloy CuRu nanoparticles(N-(CuRu)_(NP+SA)@NC)thro...Active and poisoning-resistant Ru-based electrocatalysts for the hydrogen oxidation reaction(HOR)are designed and fabricated by integrating Cu/Ru dual single atoms and alloy CuRu nanoparticles(N-(CuRu)_(NP+SA)@NC)through a strategy involving weak chemical reduction and ammonia-assisted gas-phase nitridation.The resultant N-(CuRu)_(NP+SA)@NC electrocatalysts feature nitrogen atoms coordinated to both Cu and Ru metal atoms via strong N-metal interactions.Density functional theory calculations revealed that alloyed CuRu nanoparticles and monodispersed Cu atoms are vital for altering the electronic configuration of the host Ru elements.This finely tuned structure enhanced the adsorption of H and OH and promoted CO oxidation over the N-(CuRu)_(NP+SA)@NC electrocatalyst,resulting in high alkaline HOR activity,as evidenced by the higher exchange current density of 3.74 mA cm^(-2)and high mass activity of 3.28 mAμg_(Ru)^(-1),which are far superior to those of most Ru-based catalysts reported to date.Moreover,the N-(CuRu)_(NP+SA)@NC electrocatalysts are resistant to CO poisoning and can be used at a high concentration of 1000 ppm CO with no distinct decay in the activity,in stark contrast to the commercial Pt/C catalyst under the same conditions.展开更多
基金supported by the National Natural Science Foundation of China(Nos.42477406 and 51878617)the Horizontal Scientific Research Project(No.KYY-HX-20220803)the Engineering Research Center of Ministry of Education for Renewable Energy Infrastructure Construction Technology.
文摘In this work,we constructed a three-dimensional electrochemical system(3D-ECO),which included the cathode and anode electrode plates,as well as the screening of three-dimensional particle electrodes and parameter opti-mization,for the degradation of landfill leachate(LL)containing elevated levels of tetracycline(TC),and explored its mechanism of action.Firstly,titanium-based ruthenium-iridium(Ti/RuO_(2)-IrO_(2)),titanium-based ruthenium-iridium-platinum(Ti/Pt-RuO_(2)-IrO_(2)),and titanium-based tin-antimony(Ti/SnO_(2)-Sb_(2)O_(3))were employed as an-odes in the electrocatalytic oxidation system,with titanium and stainless steel plates serving as cathodes,to construct the optimal two-dimensional electrocatalytic oxidation system(2D-ECO)through cross-comparison ex-periments.Subsequently,using granular activated carbon(GAC),coconut shell biochar(CBC),walnut shell carbon(WBC),and bamboo charcoal(BBC)as particle electrodes,a 3D-ECO system was developed.The influence of var-ious operational parameters on treating TC-containing LL was investigated.The optimal operating parameters obtained from the study was:pH=5,current density of 30 mA/cm^(2),particle dosage of 7 g/L,particle size ranging from 1.70 to 2.00 mm,and electrode spacing of 4 cm.Under these conditions,the COD removal rate of 3D-ECO within three hours was 90.25%,the TC removal rate was 72.41%,and the NH_(3)-N removal rate was 39.52%.The removal of TC followed a pseudo-first-order kinetic model.Additionally,degradation mechanisms were elucidated through electron paramagnetic resonance(EPR)spectrometer and Tert-Butanol(TBA)quenching experiments,indicating that the degradation primarily occurred through a non-radical(1O_(2))pathway.This re-search offers a comprehensive analysis of the simultaneous breakdown of intricate LL matrices and TC,enhancing our comprehension of the degradation processes and underlying mechanisms.
基金National Natural Science Foundation of China(52071274)Key Research and Development Projects of Shaanxi Province(2023-YBGY-442)Science and Technology Nova Project-Innovative Talent Promotion Program of Shaanxi Province(2020KJXX-062)。
文摘To mitigate the impact of interdiffusion reactions between the silicide slurry and Ta12W alloy substrate during vacuum sintering process on the oxidation resistance of the silicide coating,a micro-arc oxidation pretreatment was employed to construct a Ta_(2)O_(5)ceramic layer on the Ta12W alloy surface.Subsequently,a slurry spraying-vacuum sintering method was used to prepare a Si-Cr-Ti-Zr coating on the pretreated substrate.Comparative studies were conducted on the microstructure,phase composition,and isothermal oxidation resistance(at 1600℃)of the as-prepared coatings with and without the micro-arc oxidation ceramic layer.The results show that the Ta_(2)O_(5)layer prepared at 400 V is more continuous and has smaller pores than that prepared at 350 V.After microarc oxidation pretreatment,the Si-Cr-Ti-Zr coating on Ta12W alloy consists of three distinct layers:an upper layer dominated by Ti_(5)Si_(3),Ta_(5)Si_(3),and ZrSi;a middle layer dominated by TaSi_(2);a coating/substrate interfacial reaction layer dominated by Ta_(5)Si_(3).Both the Si-Cr-Ti-Zr coatings with and without the Ta_(2)O_(5)ceramic layer do not fail after isothermal oxidation at 1600℃for 5 h.Notably,the addition of the Ta2O5 ceramic layer reduces the high-temperature oxidation rate of the coating.
基金Supported by the National Key Research and Development Program of Traditional Chinese Medicine Modernization Project,China(No.2023YFC3504000)the Science and Technology Development Project of Jilin Province,China(No.20240404043ZP)the Science and Technology Innovation Cooperation Project of Changchun Science and Technology Bureau and Chinese Academy of Sciences,China(No.23SH14)。
文摘In this study,a novel polysaccharide GPA-G 2-H was derived from ginseng.Furthermore,the coherent study of its structural characteristics,fermented characteristics in vitro,as well as antioxidant mechanism of fermented product FGPA-G 2-H on Aβ25-35-induced PC 12 cells were explored.The structure of GPA-G 2-H was determined by means of zeta potential analysis,FTIR,HPLC,XRD,GC-MS and NMR.The backbone of GPA-G 2-H was mainly composed of→4)-α-D-Glcp-(1→with branches substituted at O-3.Notably,GPA-G 2-H was degraded by intestinal microbiota in vitro with total sugar content and pH value decreasing,and short-chain fatty acids(SCFAs)increasing.Moreover,GPA-G 2-H significantly promoted the proliferation of Lactobacillus,Muribaculaceae and Weissella,thereby making positive alterations in intestinal microbiota composition.Additionally,FGPA-G 2-H activated the Nrf 2/HO-1 signaling pathway,enhanced HO-1,NQO 1,SOD and GSH-Px,while inhabited Keap 1,MDA and LDH,which alleviated Aβ-induced oxidative stress in PC 12 cells.These provide a solid theoretical basis for the further development of ginseng polysaccharides as functional food and antioxidant drugs.
基金supported by the National Key Research and Development Program of China(2024YFA1612900)the National Natural Science Foundation of China(Grant No.52103365 and No.12375270)the Guangdong Innovative and Entrepreneurial Research Team Program,China(Grant No.2021ZT09L227).
文摘Fine-grained nuclear graphite is a key material in high-temperature gas-cooled reactors(HTGRs).During air ingress accidents,core graphite components undergo severe oxidation,threatening structural integrity.Therefore,understanding the oxidation behavior of nuclear graphite is essential for reactor safety.The influence of oxidation involves multiple factors,including temperature,sample size,oxidant,impurities,filler type and size,etc.The size of the filler particles plays a crucial role in this study.Five ultrafine-and superfine-grained nuclear graphite samples(5.9-34.4μm)are manufactured using identical raw materials and manufacturing processes.Isothermal oxidation tests conducted at 650℃-750℃ are used to study the oxidation behavior.Additionally,comprehensive characterization is performed to analyze the crystal structure,surface morphology,and nanoscale to microscale pore structure of the samples.Results indicate that oxidation behavior cannot be predicted solely based on filler grain size.Reactive site concentration,characterized by active surface area,dominates the chemical reaction kinetics,whereas pore tortuosity,quantified by the structural parameterΨ,plays a key role in regulating oxidant diffusion.These findings clarify the dual role of microstructure in oxidation mechanisms and establish a theoretical and experimental basis for the design of high-performance nuclear graphite capable of long-term service in high-temperature gas-cooled reactors.
基金supported by the National Natural Science Foundation of China,Nos.82204360(to HM)and 82270411(to GW)National Science and Technology Innovation 2030 Major Program,No.2021ZD0200900(to YL)。
文摘Traumatic brain injury involves complex pathophysiological mechanisms,among which oxidative stress significantly contributes to the occurrence of secondary injury.In this study,we evaluated hypidone hydrochloride(YL-0919),a self-developed antidepressant with selective sigma-1 receptor agonist properties,and its associated mechanisms and targets in traumatic brain injury.Behavioral experiments to assess functional deficits were followed by assessment of neuronal damage through histological analyses and examination of blood-brain barrier permeability and brain edema.Next,we investigated the antioxidative effects of YL-0919 by assessing the levels of traditional markers of oxidative stress in vivo in mice and in vitro in HT22 cells.Finally,the targeted action of YL-0919 was verified by employing a sigma-1 receptor antagonist(BD-1047).Our findings demonstrated that YL-0919 markedly improved deficits in motor function and spatial cognition on day 3 post traumatic brain injury,while also decreasing neuronal mortality and reversing blood-brain barrier disruption and brain edema.Furthermore,YL-0919 effectively combated oxidative stress both in vivo and in vitro.The protective effects of YL-0919 were partially inhibited by BD-1047.These results indicated that YL-0919 relieved impairments in motor and spatial cognition by restraining oxidative stress,a neuroprotective effect that was partially reversed by the sigma-1 receptor antagonist BD-1047.YL-0919 may have potential as a new treatment for traumatic brain injury.
基金supported by the Original Exploratory Program of the National Natural Science Foundation of China(No.52450012)。
文摘TiB_(2)coatings can significantly enhance the high-temperature oxidation resistance of molybdenum,which would broaden the application range of molybdenum and alloys thereof.However,traditional methods for preparing TiB_(2)coatings have disadvantages such as high equipment costs,complicated processes,and highly toxic gas emissions.This paper proposes an environmentally friendly method,which requires inexpensive equipment and simple processing,for preparing TiB_(2)coating on molybdenum via electrophoretic deposition within Na3AlF6-based molten salts.The produced TiB_(2)layer had an approximate thickness of 60μm and exhibited high density,outstanding hardness(38.2 GPa)and robust adhesion strength(51 N).Additionally,high-temperature oxidation experiments revealed that,at900℃,the TiB_(2)coating provided effective protection to the molybdenum substrate against oxidation for 3 h.This result indicates that the TiB_(2)coating prepared on molybdenum using molten salt electrophoretic deposition possesses good high-temperature oxidation resistance.
基金supported by the National Natural Science Foundation of China(No.52001034)the China Postdoctoral Science Foundation(No.2023M731677)the Postgraduate Research&Practice Innovation Program of Jiangsu Province(No.KYCX23_3032).
文摘Nano-zinc oxides(ZnO)demonstrate remarkable antibacterial properties.To further enhance the corrosion resistance and antibacterial efficiency of magnesium alloy micro-arc oxidation(MAO)coatings,this study investigates the preparation of ZnO-containing micro-arc oxidation coatings with dual functionality by incorporating nano-ZnO into MAO electrolyte.The influence of varying ZnO concentrations on the microstructure,corrosion resistance,and antibacterial properties of the coating was examined through microstructure analysis,immersion tests,electrochemical experiments,and antibacterial assays.The findings revealed that the addition of nano-ZnO significantly enhanced the corrosion resistance of the MAO-coated alloy.Specifically,when the ZnO concentration in the electrolyte was 5 g/L,the corrosion rate was more than ten times lower compared to the MAO coatings without ZnO.Moreover,the antibacterial efficacy of ZnO+MAO coating,prepared with a ZnO concentration of 5 g/L,surpassed 95%after 24 h of co-culturing with Staphylococcus aureus(S.aureus).The nano-ZnO+MAO-coated alloy exhibited exceptional degradation resistance,corrosion resistance,and antibacterial effectiveness.
基金funded by the National Key R&D Program of China(2021YFA1501101)the National Natural Science Foundation of China(No.22471103,22425105,22201111,21931001,22221001,and 22271124)+5 种基金Young Elite Scientists Sponsorship Program by CAST(2023QNRC001)the Special Fund Project of Guiding Scientific and Technological Innovation Development of Gansu Province(2019ZX-04)the 111 Project(B20027)as well as the National Natural Science Foundation of Gansu Province(22JR5RA470)the Fundamental Research Funds for the Central Universities(lzujbky-2023-eyt03)supported by the Agency for Science,Technology and Research(A*STAR)MTC Individual Research Grants(IRG)M22K2c0078.
文摘Water splitting hinges crucially on the availability of electrocatalysts for the oxygen evolution reaction.The surface reconstruction has been widely observed in perovskite catalysts,and the reconstruction degree has been often correlated with the activity enhancement.Here,a systematic study on the roles of Fe substitution in activation of perovskite LaNiO_(3)is reported.The substituting Fe content influences both current change tendency and surface reconstruction degree.LaNi_(0.9)Fe_(0.1)O_(3)is found exhibiting a volcano-peak intrinsic activity in both pristine and reconstructed among all substituted perovskites in the LaNi_(1-x)Fe_(x)O_(3)(x=0.00,0.10,0.25,0.50,0.75,1.00)series.The reconstructed LaNi_(0.9)Fe_(0.1)O_(3)shows a higher intrinsic activity than most reported NiFe-based catalysts.Besides,density functional theory calculations reveal that Fe substitution can lower the O 2p level,which thus stabilize lattice oxygen in LaNi0.9Fe0.1O3 and ensure its long-term stability.Furthermore,it is vital interesting that activity of the reconstructed catalysts relied more on the surface chemistry rather than the reconstruction degree.The effect of Fe on the degree of surface reconstruction of the perovskite is decoupled from that on its activity enhancement after surface reconstruction.This finding showcases the importance to customize the surface chemistry of reconstructed catalysts for water oxidation.
基金supported by the National Natural Science Foundation of China (No. 52374292)China Baowu Low Carbon Metallurgy Innovation Foundation, China (No. BWLCF202309)the Natural Science Foundation of Changsha City, China (No. KQ2208271)。
文摘Some active metal oxides(Al_(2)O_(3),TiO_(2),and Cr_(2)O_(3))were selected as dopants to the Al_(2)O_(3)-based ceramic shells for investment casting of K417G superalloy.The effects of dopant types and contents(0,2,5,and 8 wt.%)on the wettability and interfacial reaction between the alloy and shell were investigated by a sessile-drop experiment.The results show that increasing the Al_(2)O_(3) doping contents(0−8 wt.%)reduces the porosity(21.74%−10.08%)and roughness(3.22−1.34μm)of the shell surface.The increase in Cr_(2)O_(3) dopant content(2−8 wt.%)further exacerbates the interfacial reaction,leading to an increase in the thickness of the reaction layer(2.6−3.1μm)and a decrease in the wetting angle(93.9°−91.0°).The addition of Al_(2)O_(3) and TiO_(2) dopants leads to the formation of Al_(2)TiO_(5) composite oxides in the reaction products,which effectively inhibits the interfacial reaction.The increase in TiO_(2) dopant contents(0−8 wt.%)further promotes the formation of Al_(2)TiO_(5),which decreases the thickness of the interfacial reaction layer(3.9−1.2μm)and increases the wetting angle(95.0°−103.8°).The introduced dopants enhance the packing density of the shell surface,while simultaneously suppress the diffusion of active metal elements from the alloy matrix to the interface.
基金the financial support from the National Natural Science Foundation of China(52172110,52472231,52311530113)Shanghai"Science and Technology Innovation Action Plan"intergovernmental international science and technology cooperation project(23520710600)+1 种基金Science and Technology Commission of Shanghai Municipality(22DZ1205600)the Central Guidance on Science and Technology Development Fund of Zhejiang Province(2024ZY01011)。
文摘Investigating structural and hydroxyl group effects in electrooxidation of alcohols to value-added products by solid-acid electrocatalysts is essential for upgrading biomass alcohols.Herein,we report efficient electrocatalytic oxidations of saturated alcohols(C_(1)-C_(6))to selectively form formate using Ni Co hydroxide(Ni Co-OH)derived Ni Co_(2)O_(4)solid-acid electrocatalysts with balanced Lewis acid(LASs)and Brønsted acid sites(BASs).Thermal treatment transforms BASs-rich(89.6%)Ni Co-OH into Ni Co_(2)O_(4)with nearly equal distribution of LASs(53.1%)and BASs(46.9%)which synergistically promote adsorption and activation of OH-and alcohol molecules for enhanced oxidation activity.In contrast,BASs-enriched Ni Co-OH facilitates formation of higher valence metal sites,beneficial for water oxidation.The combined experimental studies and theoretical calculation imply the oxidation ability of C1-C6alcohols increases as increased number of hydroxyl groups and decreased HOMO-LUMO gaps:methanol(C_(1))<ethylene glycol(C_(2))<glycerol(C3)<meso-erythritol(C4)<xylitol(C5)<sorbitol(C6),while the formate selectivity shows the opposite trend from 100 to 80%.This study unveils synergistic roles of LASs and BASs,as well as hydroxyl group effect in electro-upgrading of alcohols using solid-acid electrocatalysts.
基金supported by the Special Project of the Central-Guided Local Science and Technology Development(Grant No.2022ZY2-JCYJ-01-06)the Key Research and Development Program(Grant No.2020-xxx-ZD-179-00-05)Prof.Lujun Huang Group at Harbin Institute of Technology for providing the TiBw/Ti55 composites.
文摘The oxidation behavior of Ti55 alloy and TiBw/Ti55 composites at temperatures ranging from 960 to 1000℃ was investigated by characterizing the surface and cross-section microstructure of specimens.Results showed that TiBw reinforcement accelerated the occurrence of Ti_(6O)/Ti_(3O) by dissolving oxygen in titanium in the starting oxidation stage,and the Ti_(6O)/Ti_(3O) transformed into TiO_(2) with the progression of oxidation.Meanwhile,TiBw reinforcement promoted the formation of(101)crystal planes to be beneficial to the growth of TiO_(2) twins.The cross-sectional characterization showed that the oxide layer of Ti55 alloy and TiBw/Ti55 composites from outside to inside was TiO_(2)+Al_(2)O_(3),TiO_(2),Ti-Sn compounds,Ti_(6O)/Ti_(3O) in sequence,which was confirmed by calculating the standard Gibbs free energy of the oxide nucleation.The TiBw reinforcement accelerated the occurrence of suboxides Ti_(6O)/Ti_(3O) by dissolving oxygen in titanium,and promoted the formation of(101)crystal planes which were beneficial to the growth of TiO_(2) twins.The optimal addition of TiBw induced the TiO_(2) twins,promoted the random orientation of oxides and refined the oxide size of the TiBw/Ti55 composites with 3.5%volume fractions of TiBw,resulting in the best resistance against oxidation.
基金the Jiangsu Provincial Six Talent Peaks Project(No.XCL-090)the Cooperation Project of Yangzhou City with Yangzhou University(No.YZ2023209)+1 种基金Jiaxing Key Laboratory for Creation of Animal Models&Synthesis of Lead Compounds of New Drug(No.jxsz21006)the Priority Academic Program Development of Jiangsu Higher Education Institutions for support。
文摘The synergistic effect of Se with Fe can enhance the catalytic activities of the system for oxidation reactions.Based on this principle,a series of Se/Fe materials have been invented to develop the heterogeneous catalysts with industrial application potential.However,the present methods suffer from the tedious procedures,the high reaction temperature,and the low synthetic efficiency.In this paper,we report the synthesis of Se/Fe materials just by precipitating Fe(NO_(3))_(3)with the in situ prepared aqueous NaSe/NaSeO_(3)under mild conditions.The concise method may resolve the issues hindering the large-scale applications of Se/Fe materials.
基金supported by the Natural Science Foundation of Jiangxi Province(20232ACB213005).
文摘A novel tetra-europium(III)-containing antimonotungstate,Na_(8.2)[H_(2)N(CH_(3))_(2)]_(9)[Na_(10.8)(tar)_(4)(H_(2)O)_(20)(Eu_(2)Sb_(2)W_(21)O_(72))_(2)]·44.5H_(2)O(EuSbW,H_(4)tar=dl-tartaric acid),has been synthesized and characterized.The dimeric polyoxoanion of EuSbW consists of two Dawson-like{Eu_(2)Sb_(2)W_(21)}units bridged by four dl-tartaric acid ligands.The adjacent carboxyl and hydroxy groups in each tartaric acid simultaneously chelate with W and Eu atoms from different{Eu_(2)Sb_(2)W_(21)}units,thereby forming the dimeric structure.EuSbW represents an extremely rare polyoxometalate where four tartaric acid ligands function as connectors to bridge two{Eu_(2)Sb_(2)W_(21)}units.Additionally,EuSbW exhibits excellent catalytic activity and reusability in the oxidation of thioethers and alcohols,achieving 100%conversion and>99%selectivity for various thioethers,and 85–100%conversion with 90–99%selectivity for diverse alcohols under mild conditions.
基金financially supported by the National Key Technology R&D Program of China(No.2021YFB3500801)
文摘Enhancing the activity of photocatalysts is a critical challenge for improving the photocatalytic degradation of contaminated wastewater.Here,a novel Ce single-atom-doped titanate nanotube photocatalyst(CeH_(2)Ti_(2)O_(5)·H_(2)O)was successfully synthesized using a onepot solvothermal method.Degradation experiments revealed that the optimal Ce doping ratio was 1.0%.The ultraviolet-visible diffuse reflectance spectroscopy results showed that the bandgap of the Ce-doped sample decreased from 3.02 to 2.87 eV,enhancing the absorption in the visible spectral range.At the same time,the BrunauerEmmett-Teller specific surface area increased from 63.68 to 88.95 m^(2)g^(-1).The 1.0%Ce-H_(2)Ti_(2)O_(5)·H_(2)O(HTC_(1))could degrade 99.04%of 100 mg L-1rhodamine B(RhB)after 40 min of visible-light irradiation.The degradation efficiency decreased by only 21.24%after five cycles.The results of free-radical quenching and electron spin resonance spectroscopy analyses indicated that HTC_(1)achieved efficient degradation of RhB through a direct hole oxidation mechanism.Compared with pure protonated titanate nanotubes(H_(2)Ti_(2)O_(5)·H_(2)O),HTC_(1)had a higher specific surface area,more electron traps,narrower bandgap,longer hole lifetime,and suppressed photogenerated charge recombination rate owing to the Ce single-atom doping.
基金supported by Gansu Cuihua Technology Co.,Ltd.(H2020292)Science and Technology Planning of Baiyin City,Fundamental Research Funds for the Central Universities (buctrc202208)+2 种基金Engineering Research Center of Non-metallic Minerals of Zhejiang Province and the Beijing Engineering Center for Hierarchical Catalysts. Central Government Guiding Funds for Local Science and Technology Development (2022ZY015)Nanjiang Technology Project(2023AB028)Open Laboratory of State Key Laboratory of Organic and Inorganic Composites (oic-202301006)。
文摘Coupling adsorption and in-situ Fenton-like oxidation process was developed for Methylene blue(MB) using refined iron-containing lowgrade attapulgite(ATP) clay, and the removal mechanism was investigated. The MB was initially adsorbed on the porous ATPs, and then the enriched MB was removed by the H2O2-assisted Fenton-like oxidation with the iron-containing ATP catalyst. Under optimal conditions, the ATP powder exhibits the maximum removal efficiency of 100% with negligible iron leaching(1.5 mg L^(-1)) and no sludge formation. Furthermore,polysulfone/ATP(PSF/ATP) pellets were fabricated through a water-induced phase separation process to construct a fixed-bed reactor(FBR) for continuous contaminant removal. For the first cycle, the maximum adsorption capacity was 15.5 L with an outlet MB concentration of1.973 mg L-1(< 2 mg L^(-1), GB4287-2012) using the PSF/ATP pellets containing 50.0 g of ATP powders, and the maximum Fenton-like oxidation capacity was 35.5 L with the outlet concentration of 0.831 mg L^(-1). After five cycles, the total treated volume of the MB solution was ca. 255 L, and the efficiency remained above 99%. After 10 h of continuous treatment towards practical resin industrial wastewater, the chemical oxygen demand(COD) removal efficiency was still measured at 83.05%, costing 0.398 $ m^(-3). These results demonstrate the practical applicability of iron-containing low-grade ATP clay for textile water treatment.
基金supported by the Liaoning Youth Science Foundation Project B Category(Contract No.2025010041-JH6/1010)the National Natural Science Foundation of China(Grant No.52471103).
文摘Press hardening with manganese-boron steels is a prominent manufacturing technique that allows for reduced weight and expense in automotive construction,while providing enhanced crash performance.Nevertheless,the development of a loosely attached oxide layer during press hardening and following additional processing of the layer presents a significant risk to the dimensional precision of the completed product.Here,we develop a new preprocessing approach to address the scale spallation issue by introducing trace amounts of silicate and tungstate into the rinsing solution following pickling.We demonstrate that the pre-deposited membrane promotes the formation of a noticeably thinner,more continuous and stickier oxide scale at high temperatures,enabling the direct application of automobile painting onto the scale.Our research provides an economical remedy to the troublesome scale flaking issue without requiring any modifications to the existing production line,and conveys a thorough comprehension of the mechanism by which the preprocessed membrane resists high-temperature oxidation.
基金supported by the National Natural Science Foundation of China(22478087,22368014)Guizhou Provincial S&T Project(GCC[2023]011,ZK[2022]011)Guizhou Provincial Higher Education Institution Program(Qianjiaoji[2023]082).
文摘Photocatalytic activation of C-H bonds is versatile but challenging for undergoing oriented conversion processes.Herein,a spatially site-isolated heterojunction(ZS-Vs/ZIS)of ZnIn2S4 with strong Lewis acidity(ZIS)and ZnS with S-vacancy(ZS-Vs)is constructed for activating α-C‒H bond and forming·O_(2)^(-)to cleave the C-H bond,respectively.ZS-Vs/ZIS displays outstanding performance in visible-light partial photooxidation of bio-based 5-hydroxymethylfurfural(HMF)to 2,5-diformylfuran(DFF)in an unprecedented yield of 95.7%at 25°C.In-situ experiments and calculations reveal that Zn sites of ZIS serve as hole enrichment to adsorb HMF for α-C‒H activation via ligand-to-metal charge transfer.Shallow trap states introduced by S-vacancy in ZS-Vs act as an electron pool to realize directed O_(2) activation into·O_(2)^(-)for breaking pre-activated α-C‒H bond in HMF to exclusively give DFF.Moreover,ZS-Vs/ZIS has good recyclability and universality in the photooxidation of various alcohols to carbonyls(86.4-95.6%yields).The synergistic C-H activation/breaking strategy exhibits high potential in targeted photocatalytic transformations.
基金supported by the National Natural Science Foundation of China(Grant Nos.51991351 and51903132)the Young Elite Scientist Sponsorship Program by CAST(No.2022QNRC001).
文摘Different reactive flame retardants have been extensively developed for vinyl ester resins(VERs),but very few of them can yield a flame-retardant resin that meets defined standards(e.g.UL-94 V-0 rating).In this work,phosphorous-containing 1-vinylimidazole salts(called VIDHP and VIDPP)were synthesized through the facile neutralization of the acid and 1-vinylimidazole.VIDHP and VIDPP were then applied as flame-retardant crosslinking agents of VERs,by which phosphorus-containing groups could be incorporated into the resin chain via ionic bonds.VIDHP/VER and VIDPP/VER showed a high curing activity and can be well cured in moderate temperatures.With 20 wt.%additions of VIDHP and VIDPP,VIDHP20/VER,and VIDPP20/VER presented a limiting oxygen index value of 29.7%and 28.4%,respectively,with the latter achieving a UL 94 V0 rating.In the cone calorimetric test,compared to the unmodified VERs,VIDPP20/VER exhibited large reductions in the peak heat release rate,total heat release rate,and total smoke release rate while VIDHP20/VER demonstrated comparatively inferior performance in terms of the heat release.VIDHP20/VER and VIDPP20/VER showed good thermal stability and presented a little lower glass transition temperature than the control sample.VIDPP with a low phosphorus oxidation state(+1)demonstrated high flame-retardant activities in the gaseous phase,whereas VIDHP with a high phosphorus oxidation state(+5)primarily exhibited efficacy in the condensed phase.
基金the financial support from National Natural Science Foundation of China(Nos.52100204 and 52330005)Beijing Outstanding Young Scientist Program(No.BJJWZYJH01201910004016)。
文摘The widespread occurrence of antibiotics in wastewater aroused serious attention.UV-based advanced oxidation processes(UV-AOPs)are powerful technologies in removing antibiotics in wastewater,which include UV/catalyst,UV/H_(2)O_(2),UV/Fenton,UV/persulfate,UV/chlorine,UV/ozone,and UV/peracetic acid.In this review,we collated recent advances in application of UV-AOPs for the abatement of fiuoroquinolones(FQs)as widely used class of antibiotics.Representative FQs of ciprofioxacin,norfioxacin,ofioxacin,and enrofioxacin were most extensively studied in the state-of-art studies.The evolvement of gas-state and solid-state UV light sources was presented and batch and continuous fiow UV reactors were compared towards practical applications in UV-AOPs.Generally,degradation of FQs followed the pseudo-first order kinetics in UV-AOPs and strongly affected by the operating factors and components of water matrix.Participation of reactive species and transformation mechanisms of FQs were compared among different UV-AOPs.Challenges and future prospects were pointed out for providing insights into the practical application of UV-AOPs for antibiotic remediation in wastewater.
文摘Active and poisoning-resistant Ru-based electrocatalysts for the hydrogen oxidation reaction(HOR)are designed and fabricated by integrating Cu/Ru dual single atoms and alloy CuRu nanoparticles(N-(CuRu)_(NP+SA)@NC)through a strategy involving weak chemical reduction and ammonia-assisted gas-phase nitridation.The resultant N-(CuRu)_(NP+SA)@NC electrocatalysts feature nitrogen atoms coordinated to both Cu and Ru metal atoms via strong N-metal interactions.Density functional theory calculations revealed that alloyed CuRu nanoparticles and monodispersed Cu atoms are vital for altering the electronic configuration of the host Ru elements.This finely tuned structure enhanced the adsorption of H and OH and promoted CO oxidation over the N-(CuRu)_(NP+SA)@NC electrocatalyst,resulting in high alkaline HOR activity,as evidenced by the higher exchange current density of 3.74 mA cm^(-2)and high mass activity of 3.28 mAμg_(Ru)^(-1),which are far superior to those of most Ru-based catalysts reported to date.Moreover,the N-(CuRu)_(NP+SA)@NC electrocatalysts are resistant to CO poisoning and can be used at a high concentration of 1000 ppm CO with no distinct decay in the activity,in stark contrast to the commercial Pt/C catalyst under the same conditions.
