Poly(butylene adipate-terephthalate)(PBAT),as one of the most common and promising biodegradable plastics,has been widely used in agriculture,packaging,and other industries due to its strong biodegradability propertie...Poly(butylene adipate-terephthalate)(PBAT),as one of the most common and promising biodegradable plastics,has been widely used in agriculture,packaging,and other industries due to its strong biodegradability properties.It is well known that PBAT suffers a series of natural weathering,mechanical wear,hydrolysis,photochemical transformation,and other abiotic degradation processes before being biodegraded.Therefore,it is particularly important to understand the role of abiotic degradation in the life cycle of PBAT.Since the abiotic degradation of PBAT has not been systematically summarized,this review aims to summarize the mechanisms and main factors of the three major abiotic degradation pathways(hydrolysis,photochemical transformation,and thermochemical degradation)of PBAT.It was found that all of them preferentially destroy the chemical bonds with higher energy(especially C-O and C=O)of PBAT,which eventually leads to the shortening of the polymer chain and then leads to reduction in molecular weight.The main factors affecting these abiotic degradations are closely related to the energy or PBAT structure.These findings provide important theoretical and practical guidance for identifying effective methods for PBAT waste management and proposing advanced schemes to regulate the degradation rate of PBAT.展开更多
Dissolved organic matter(DOM)is very important in aquatic environments,yet it is challenging to characterize DOM as a highly complex mixture of thousands of molecules,and the knowledge of the effects of different degr...Dissolved organic matter(DOM)is very important in aquatic environments,yet it is challenging to characterize DOM as a highly complex mixture of thousands of molecules,and the knowledge of the effects of different degradation processes on different molecules remains limited.This study examined the distribution and degradation of DOM in a large subtropical river using optical techniques and Fourier transform ion cyclotron resonance mass spectrometry(FT-ICR-MS).At the molecular level,DOM was mainly composed of CHO and lignin-like compounds,which was related to the dominance of forestland in the watershed and resulted in a low biological lability index(MLBL).The modified aromaticity index(AI_(mod)),unsaturation degree(DBE),and humic content(HIX)decreased while MLBL,H/C,absorption spectral slope(S_(275–295)),and biological index(BIX)increased in the estuarine zone due to the increasing autochthonous contribution.Photo-and microbial degradation resulted in a similar decrease in the bulk dissolved organic carbon,while they showed opposite effects on the DOM composition.Photo-degradation removed all fluorescent components and decreased molecular weight,HIX,AI_(mod),DBE,%CHO,%lignin-like,%tannin-like,and%condensed aromatic-like compounds.In contrast,bio-degradation preferentially consumed lipid-like,protein-like,and carbohydrate-like compounds,with increases in%ligninlike,%tannin-like,%condensed aromatic-like compounds,and humic-like fluorescent components.Overall,the application of ultra-high resolutionmass spectrometry provided valuable insights into the composition and behavior of DOM at themolecular level and revealed the contrasting effects of photo-and microbial degradation on different compounds.These results have implications for better understanding the composition and transformation of aquatic DOM.展开更多
The selection of carbon sources and the biosynthesis of polyhydroxybutyrate(PHB)by the Azotobacter vinelandii N-15 strain using renewable raw materials were investigated.Among the tested substrates(starch,sucrose,mola...The selection of carbon sources and the biosynthesis of polyhydroxybutyrate(PHB)by the Azotobacter vinelandii N-15 strain using renewable raw materials were investigated.Among the tested substrates(starch,sucrose,molasses,bran),molasses as the carbon source yielded the highest PHB production.The maximum polymer yield(26%of dry biomass)was achieved at a molasses concentration of 40 g/L.PHB formation was confirmed via thinlayer chromatography,gas chromatography and Fourier transform infrared spectroscopy.Composite films based on PHB,polylactic acid(PLA),and their blends were fabricated using the solvent casting.The biodegradation of these films was studied with bacteria isolated from plastic-contaminated soil.These bacteria utilized the biopolymers as their sole carbon source,with the biodegradation process lasting three months.Structural and chemical changes in the films were analyzed using FTIR spectroscopy,differential scanning calorimetry,and thermogravimetry.Among the microorganisms used to study the biodegradation of PHB,PLA,and their blends,Streptomyces sp.K2 and Streptomyces sp.K4 exhibited the highest biodegradation efficiency.PHB-containing films demonstrated significant advantages over other biodegradable polymers,as they degrade under aerobic conditions via enzymatic hydrolysis using microbial depolymerases.展开更多
This paper presents a multi-scale experimental investigation of the weathering degradation of red mudstone.Natural rocks were extracted from the surface ground to 120 m,inwhich three sets of samples were selected to c...This paper presents a multi-scale experimental investigation of the weathering degradation of red mudstone.Natural rocks were extracted from the surface ground to 120 m,inwhich three sets of samples were selected to consider the different initial rock fabrics.The long-term relative humidity(RH)cycles under two amplitudes were imposed on red mudstone to simulate the weathering process.After RH cycles,a series of uniaxial compression tests,Brazilian splitting tests and bender-extender element tests were carried out to examine the reduction in strength and stiffness.The objective of this study is to develop an extended stress-volume framework characterizing the degradation of natural red mudstone both at microscale and macroscale.Accompanied by the irreversible swelling of the rock specimen is the progressive degradation of strength,stiffness and Poisson's ratio.A unified exponential degradation model in terms of the irreversible volumetric strain was thus proposed to capture such a degradation pattern.The effect of the initial rock fabric was evident.The highest degradation rate and potential were identified in slightly weathered specimens.Significant slaking of aggregates and crack propagation were confirmed by scanning electron microscope(SEM)micrographs,which were considered as the main consequence of structure damage leading to degradation of mechanical properties.The structure damage during RH cycles denoted the hysteresis nature in the response to the cycling hydraulic reaction,in turn causing the increase in volumetric strain.Thus,the stress-volume relation rather than the suction relation was found in more reasonable agreement with the experimental results.展开更多
Wide bandgap semiconductors are typically activated under ultraviolet(UV)light irradiation for volatile organic compounds(VOCs)degradation.However,our previous study discovered that certain VOCs can interact with some...Wide bandgap semiconductors are typically activated under ultraviolet(UV)light irradiation for volatile organic compounds(VOCs)degradation.However,our previous study discovered that certain VOCs can interact with some wide bandgap semiconductors,formatting an intermediate bandgap between the VOCs and the conduction band of wide bandgap semiconductor,thus inducing visible light activation of the system,and photo-generated electrons are excited by visible light and transferred from the VOCs to the conduction band of semiconductor.In this work,BaTiO_(3),traditionally is not active under visible light irradiation,however showed degradation rates of 100%and 20%for styrene and toluene under visible light,respectively.Density functional theory(DFT)calculations indicate that the adsorption of styrene or toluene on the BaTiO_(3)surface reduces its bandgap from 2.93 eV to 1.36 eV and 2.26 eV,respectively.The intermediate bandgap in this system is primarily formed by the valence band of BaTiO_(3)and the VOCs,and indicating that photo-generated electrons directly transfer from BaTiO_(3)to the VOCs under visible light,inducing degradation reactions of VOCs,i.e.,this work discovered a new transfer pathway of photo-electrons direct from the valence band of BaTiO_(3)to VOCs,while photo-electrons are from VOCs to the conductive band of wide-bandgap semiconductors in our previous work.展开更多
Exploration of stable metal single-site supported porous graphitic carbon nitride(PCN)nanostructures and the development of maximum atom utilization for enhanced photocatalytic oxidation of antibiotics remains a chall...Exploration of stable metal single-site supported porous graphitic carbon nitride(PCN)nanostructures and the development of maximum atom utilization for enhanced photocatalytic oxidation of antibiotics remains a challenge in current research.This work proposed a one-step thermal copolymerization to obtain Cu(Ⅰ)doping porous carbon nitride(CUCN)through a spontaneously reducing atmosphere by urea in a covered crucible.The obtained CUCN had crumpled ultrathin nanosheets and mesoporous structures,which possessed higher specific surface areas than PCN.From X-ray absorption near edge structure(XANES)and Fourier transform extended X-ray absorption fine structure(FT-EXAFS)spectra analysis,the Cu doping existed in the oxidation state of Cu(Ⅰ)as single atoms anchored on the 2D layers of CN through two N neighbors,thereby facilitating efficient pathways for the transfer of photoexcited charge carriers.Furthermore,the photoluminescence(PL)spectra,electrochemical impedance spectra(EIS)and transient photocurrent response test proved the improved separation and transfer of photoexcited charge carriers for Cu(Ⅰ)introduction.Consequently,the photocatalytic activity of CUCN was much better than that of PCN for antibiotics norfloxacin(NOR),with 4.7-fold higher degradation reaction rate constants.From species-trapping experiments and density function theory(DFT)calculations,the Cu single atoms in Cu-N_(2)served as catalytic sites that could accelerate charge transfer and facilitate the adsorption of molecular oxygen to produce active species.The stable Cu(Ⅰ)embedded in the layer structure led to the excellent recycling test and remained stable after four runs of degradation and even thermal regenerated treatment.The degradation paths of NOR by CUCN under visible light were also demonstrated.Our work sheds light on a sustainable and practical approach for achieving stable metal single-atom doping and enhancing photocatalytic degradation of aqueous pollutants.展开更多
Nicotine,also known as nicotinic norephedrine,is one of the main alkaloids present in tobacco plants.In recent years,due to the increase in tobacco production and smoking population,the environmental and health issues...Nicotine,also known as nicotinic norephedrine,is one of the main alkaloids present in tobacco plants.In recent years,due to the increase in tobacco production and smoking population,the environmental and health issues caused by nicotine have become increasingly severe.Traditional methods have proven ineffective in efficiently degrading residual nicotine.To address this issue,scientists both domestically and internationally have turned to biodegradation methods to tackle the environmental and health problems caused by residual nicotine.In this study,an enrichment method was used to screen bacteria with nicotine-degrading capabilities from the soil of tobacco planting sites at the Tobacco Research Institute of Heilongjiang in Bin County,Harbin City.Through phenotypic observations and 16S rDNA identification,a bacterial strain identified as Pseudomonas hunanensis MGJ-2 was isolated,capable of utilizing nicotine as a carbon and nitrogen source for growth.High-performance liquid chromatography(HPLC)-1 analysis revealed that within 25 h,strain MGJ-2 could degrade nicotine 500 mg·L^(-1) with an efficiency exceeding 99.9%.Strain MGJ-2 was applied to tobacco,and after 15 days of incubation and fermentation,it degraded 10.57%of nicotine in tobacco.Overall,the discovery of strain MGJ-2 enriched the resources of nicotine-degrading strains.Its remarkable biodegradation performance held immense potential for future biodegradation of nicotine in tobacco.展开更多
BACKGROUND Gastric cancer(GC)is a prevalent malignancy with a substantial health burden and high mortality rate,despite advances in prevention,early detection,and treatment.Compared with the global average,Asia,notabl...BACKGROUND Gastric cancer(GC)is a prevalent malignancy with a substantial health burden and high mortality rate,despite advances in prevention,early detection,and treatment.Compared with the global average,Asia,notably China,reports disproportionately high GC incidences.The disease often progresses asymptoma-tically in the early stages,leading to delayed diagnosis and compromised out-comes.Thus,it is crucial to identify early diagnostic biomarkers and enhance treatment strategies to improve patient outcomes and reduce mortality.METHODS Retrospectively analyzed the clinical data of 148 patients with GC treated at the Civil Aviation Shanghai Hospital between December 2022 and December 2023.The associations of coagulation indices-partial thromboplastin time(APTT),prothrombin time(PT),thrombin time(TT),fibrinogen,fibrinogen degradation products(FDP),fasting blood glucose,and D-dimer(D-D)with TNM stage and distant metastasis were examined.RESULTS Prolongation of APTT,PT,and TT was significantly correlated with the GC TNM stage.Hence,abnormal coagulation system activation was closely related to disease progression.Elevated FDP and D-D were significantly associated with distant metastasis in GC(P<0.05),suggesting that increased fibrinolytic activity contributes to increased metastatic risk.CONCLUSION Our Results reveal coagulation indices,FDPs as GC biomarkers,reflecting abnormal coagulation/fibrinolysis,aiding disease progression,metastasis prediction,and helping clinicians assess thrombotic risk for early intervention and personalized treatment plans.展开更多
With the approaching of large-scale retirement of power lithium-ion batteries(LIBs),their urgent handling is required for environmental protection and resource reutilization.However,at present,substantial spent power ...With the approaching of large-scale retirement of power lithium-ion batteries(LIBs),their urgent handling is required for environmental protection and resource reutilization.However,at present,substantial spent power batteries,especially for those high recovery value cathode materials,have not been greenly,sustainably,and efficiently recycled.Compared to the traditional recovery method for cathode materials with high energy consumption and severe secondary pollution,the direct repair regeneration,as a new type of short-process and efficient treatment methods,has attracted widespread attention.However,it still faces challenges in homogenization repair,electrochemical performance decline,and scaling-up production.To promote the direct regeneration technology development of failed NCM materials,herein we deeply discuss the failure mechanism of nickel-cobalt-manganese(NCM)ternary cathode materials,including element loss,Li/Ni mixing,phase transformation,structural defects,oxygen release,and surface degradation and reconstruction.Based on this,the detailed analysis and summary of the direct regeneration method embracing solid-phase sintering,eutectic salt assistance,solvothermal synthesis,sol-gel process,spray drying,and redox mediation are provided.Further,the upcycling strategy for regeneration materials,such as single-crystallization and high-nickelization,structural regulation,ion doping,and surface engineering,are discussed in deep.Finally,the challenges faced by the direct regeneration and corresponding countermeasures are pointed out.Undoubtedly,this review provides valuable guidance for the efficient and high-value recovery of failed cathode materials.展开更多
In this paper,the property degradation micromechanism of Al-5.10Cu-0.65 Mg-0.8Mn(wt%)alloy induced by 0.5 wt%Fe minor addition was revealed by atomic-scale scanning transmission electron microscopy and energy-dispersi...In this paper,the property degradation micromechanism of Al-5.10Cu-0.65 Mg-0.8Mn(wt%)alloy induced by 0.5 wt%Fe minor addition was revealed by atomic-scale scanning transmission electron microscopy and energy-dispersive X-ray spectroscopy coupled with first-principles calculations.The results show that the Fe minor addition to the Al-Cu-Mg-Mn alloy leads to a slight reduction of grain size and the formation of coarse Al7Cu2Fe constituent particles.Fe tends to segregate into the T-phase dispersoids,θ'-,and S-phase precipitates by preferentially occupying Cu or Mn sites in these phase structures.The apparent Fe segregation contributes to an increase in stiffness of the T-phase and S-phase but decreased stiffness of theθ'phase.Formation of the coarse Al7Cu2Fe constituent particles and decreased stiffness of main precipitatesθ'containing Fe result in the degraded strength of the Al-Cu-Mg-Mn-Fe alloy.Further study reveals that corrosion resistance degradation of the Al-Cu-Mg-Mn-Fe alloy is associated with the increased width of precipitation free zones and consecutive grain boundary precipitates.The obtained results have significant implications for the usage of recycled Al alloys and the potential design strategies of high-performance alloys containing Fe.展开更多
Banana fruit ripening is a highly regulatory process involving various layers consisting of transcriptional regulation,epigenetic factor,and post-translational modification.Previously,we reported that MaERF11 cooperat...Banana fruit ripening is a highly regulatory process involving various layers consisting of transcriptional regulation,epigenetic factor,and post-translational modification.Previously,we reported that MaERF11 cooperated with MaHDA1 to precisely regulate the transcription of ripening-associated genes via histone deacetylation.However,whether MaERF11 is subjected to post-translational modification during banana ripening is largely unknown.In this study,we found that MaERF11 targeted a subset of starch degradation-related genes using the DNA affinity purification sequence(DAP-Seq)approach.Electrophoretic mobility shift assay(EMSA)and dual-luciferase reporter assay(DLR)demonstrated that MaERF11 could specifically bind and repress the expression of the starch degradation-related genes MaAMY3,MaBAM2 and MaGWD1.Further analyses of yeast two-hybrid(Y2H),bimolecular fluorescence complementation(BiFC)and Luciferase complementation imaging(LCI)assays indicated that MaERF11 interacted with the ubiquitin E3 ligase MaRFA1,and this interaction weakened the MaERF11-mediated transcriptional repression capacity.Collectively,our results suggest an additional regulatory layer in which MaERF11 regulates banana fruit ripening and expands the regulatory network in fruit ripening at the post-translational modification level.展开更多
At present,carbon capture and storage(CCS)is the only mature and commercialized technology capable of effectively and economically reducing greenhouse gas emissions to achieve a significant and immedi-ate impact on th...At present,carbon capture and storage(CCS)is the only mature and commercialized technology capable of effectively and economically reducing greenhouse gas emissions to achieve a significant and immedi-ate impact on the CO_(2) level on Earth.Notably,long-term geological storage of captured CO_(2) has emerged as a primary storage method,given its minimal impact on surface ecological environments and high level of safety.The integrity of CO_(2) storage wellbores can be compromised by the corrosion of steel casings and degradation of cement in supercritical CO_(2) storage environments,potentially leading to the leakage of stored CO_(2) from the sites.This critical review endeavors to establish a knowledge foundation for the cor-rosion and materials degradation associated with geological CO_(2) storage through an in-depth examina-tion and analysis of the environments,operation,and the state-of-the-art progress in research pertaining to the topic.This article discusses the physical and chemical properties of CO_(2) in its supercrit-ical phase during injection and storage.It then introduces the principle of geological CO_(2) storage,consid-erations in the construction of storage systems,and the unique geo-bio-chemical environment involving aqueous media and microbial communities in CO_(2) storage.After a comprehensive analysis of existing knowledge on corrosion in CO_(2) storage,including corrosion mechanisms,parametric effects,and corro-sion rate measurements,this review identifies technical gaps and puts forward potential avenues for fur-ther research in steel corrosion within geological CO_(2) storage systems.展开更多
Although solar steam generation strategy is efficient in desalinating seawater,it is still challenging to achieve continuous solar-thermal desalination of seawater and catalytic degradation of organic pollutants.Herei...Although solar steam generation strategy is efficient in desalinating seawater,it is still challenging to achieve continuous solar-thermal desalination of seawater and catalytic degradation of organic pollutants.Herein,dynamic regulations of hydrogen bonding networks and solvation structures are realized by designing an asymmetric bilayer membrane consisting of a bacterial cellulose/carbon nanotube/Co_(2)(OH)_(2)CO_(3)nanorod top layer and a bacterial cellulose/Co_(2)(OH)_(2)CO_(3)nanorod(BCH)bottom layer.Crucially,the hydrogen bonding networks inside the membrane can be tuned by the rich surface–OH groups of the bacterial cellulose and Co_(2)(OH)_(2)CO_(3)as well as the ions and radicals in situ generated during the catalysis process.Moreover,both SO_(4)^(2−)and HSO_(5)−can regulate the solvation structure of Na^(+)and be adsorbed more preferentially on the evaporation surface than Cl^(−),thus hindering the de-solvation of the solvated Na^(+)and subsequent nucleation/growth of NaCl.Furthermore,the heat generated by the solar-thermal energy conversion can accelerate the reaction kinetics and enhance the catalytic degradation efficiency.This work provides a flow-bed water purification system with an asymmetric solar-thermal and catalytic membrane for synergistic solar thermal desalination of seawater/brine and catalytic degradation of organic pollutants.展开更多
BiVO_(4)porous spheres modified by ZnO were designed and synthesized using a facile two-step method.The resulting ZnO/BiVO_(4)composite catalysts have shown remarkable efficiency as piezoelectric catalysts for degradi...BiVO_(4)porous spheres modified by ZnO were designed and synthesized using a facile two-step method.The resulting ZnO/BiVO_(4)composite catalysts have shown remarkable efficiency as piezoelectric catalysts for degrading Rhodamine B(RhB)unde mechanical vibrations,they exhibit superior activity compared to pure ZnO.The 40wt%ZnO/BiVO_(4)heterojunction composite displayed the highest activity,along with good stability and recyclability.The enhanced piezoelectric catalytic activity can be attributed to the form ation of an I-scheme heterojunction structure,which can effectively inhibit the electron-hole recombination.Furthermore,hole(h+)and superoxide radical(·O_(2)^(-))are proved to be the primary active species.Therefore,ZnO/BiVO_(4)stands as an efficient and stable piezoelectric catalyst with broad potential application in the field of environmental water pollution treatment.展开更多
Graphdiyne(GDY)and its derivatives have been considered ideal supporting materials for nanoscale active particles because of their unique atomic and electronic structure.An efficient bi-metal Cu-Pd catalyst was added ...Graphdiyne(GDY)and its derivatives have been considered ideal supporting materials for nanoscale active particles because of their unique atomic and electronic structure.An efficient bi-metal Cu-Pd catalyst was added to produce the uniform deposition of Pd nano-clusters with an average size of~0.95 nm on hydrogen-substituted GDY(HGDY)nanosheets.With the assistance of NaBH4,the resulting Pd/H-GDY was very effective in the degradation of 4-nitrophenol(4-NP),whose conversion was sharply increased to 97.21%in 100 s with a rate constant per unit mass(k`)of 8.97×10^(5)min−1 g^(−1).Additionally,dyes such as methyl orange(MO)and Congo red(CR)were completely degraded within 180 and 90 s,respectively.The Pd/H-GDY maintained this activity after 5 reduction cycles.These results highlight the promising performance of Pd/H-GDY in catalyzing the degradation of various pollutants,which is attributed to the combined effect of the largeπ-conjugated structure of the H-GDY nanosheets and the evenly distributed Pd nanoclusters.展开更多
Microplastics(MPs) are an emerging environmental pollutant and have penetrated the most remote and primitive areas. MPs degradation has received widespread attention. Manganese(Mn) is a highly reactive metal element i...Microplastics(MPs) are an emerging environmental pollutant and have penetrated the most remote and primitive areas. MPs degradation has received widespread attention. Manganese(Mn) is a highly reactive metal element in the environment, yet its contribution to MPs degradation remains unclear. Herein,we simulated the aging of polyethylene MPs with Mn(Ⅱ) under aqueous conditions at pH 5 and 8 for720 days. Mn greatly promoted the MPs degradation, and the average particle sizes of polyethylene MPs were reduced from 9.2 μm to 5.9 μm after aging at pH 5 under light irradiation for 720 days. Plenty of oxygen-containing groups were generated on the MPs surfaces, and the carbonyl index remarkably increased, reaching four times that of the control without adding Mn. Mechanistically, the adsorbed Mn(Ⅱ)on the MPs surfaces were primarily oxidized to high-valence Mn(Ⅲ/Ⅳ) profited from the photoproduced radicals, followed by the MPs oxidation via Mn(Ⅲ/Ⅳ), which were reduced to regenerate Mn(Ⅱ), initiating a new redox cycling. During the degradation, dissolved organic matter was continuously released, mainly including bisphenol A and phthalic acid esters. Mn acts as a catalyst to accelerate the MPs degradation by redox cycling. Our results provide a new insight into the mechanisms of abiotic degradation of MPs in aqueous environments.展开更多
As antibiotic pollutants cannot be incompletely removed by conventional wastewater treatment plants,ultraviolet(UV)based advanced oxidation processes(AOPs)such as UV/persulfate(UV/PS)and UV/chlorine are increasingly c...As antibiotic pollutants cannot be incompletely removed by conventional wastewater treatment plants,ultraviolet(UV)based advanced oxidation processes(AOPs)such as UV/persulfate(UV/PS)and UV/chlorine are increasingly concerned for the effective removal of antibiotics from wastewaters.However,the specific mechanisms involving degradation kinetics and transformation mechanisms are not well elucidated.Here we report a detailed examination of SO_(4)•−/Cl•-mediated degradation kinetics,products,and toxicities of sulfathiazole(ST),sarafloxacin(SAR),and lomefloxacin(LOM)in the two processes.Both SO_(4)•−/Cl•-mediated transformation kinetics were found to be dependent on pH(P<0.05),which was attributed to the disparate reactivities of their individual dissociated forms.Based on competition kinetic experiments and matrix calculations,the cationic forms(H_(2)ST^(+),H_(2)SAR^(+),and H_(2)LOM^(+))were more highly reactive towards SO_(4)•−in most cases,while the neutral forms(e.g.,HSAR^(0)and HLOM^(0))reacted the fastest with Cl•for the most of the antibiotics tested.Based on the identification of 31 key intermediates using tandem mass spectrometry,these reactions generated different products,of which the majority still retained the core chemical structure of the parent compounds.The corresponding diverse transformation pathways were proposed,involving S−N breaking,hydroxylation,defluorination,and chlorination reactions.Furthermore,the toxicity changes of their reaction solutions as well as the toxicity of each intermediate were evaluated by the vibrio fischeri and ECOSAR model,respectively.Many primary by-products were proven to be more toxic than the parent chemicals,raising the wider issue of extended potency for these compounds with regards to their ecotoxicity.These results have implications for assessing the degradative fate and risk of these chemicals during the AOPs.展开更多
Through quenching and tempering(QT)and quenching and partitioning(Q&P)processes,this study aimed to investigate the effects of microstructural modifications on the corrosion behavior and corrosion-assisted mechani...Through quenching and tempering(QT)and quenching and partitioning(Q&P)processes,this study aimed to investigate the effects of microstructural modifications on the corrosion behavior and corrosion-assisted mechanical degradation of medium Ni-bearing steel.The primary objective was the identification of strategies for the enhancement of the long-term lifespan and reliability of these alloys in neutral aqueous environments.Various electrochemical evaluations and microstructural characterizations were conducted to elucidate the relationship between heat treatment processes and corrosion behavior.The findings reveal that the conventional Q&P process formed partitioned austenite with a coarse size within the martensitic matrix,which led to an uneven distribution of Ni and high kernel average misorientation and resulted in an increased susceptibility to corrosion and corrosion-induced mechanical degradation.In addition,the corroded QT sample displayed preferential attacks around cementite clusters due to selective dissolution.By contrast,a slightly higher partitioning temperature,just above the martensite transformation start temperature,provided finely distributed austenite within bainite in the microstructure,which exhibited lower corrosion kinetics and reduced susceptibility to mechanical degradation in the corrosive environment.This study highlights the potential of microstructural optimization through the Q&P process with a high partitioning temperature as an effective technical strategy for achieving the superior durability and reliability of medium Ni-bearing steel alloys in neutral aqueous environments.展开更多
The in vitro and in vivo degradation behavior of an experimental Mg alloy with high corrosion resistance has been investigated and compared with that of a commercial AZ31 Mg alloy with a similar chemical composition.I...The in vitro and in vivo degradation behavior of an experimental Mg alloy with high corrosion resistance has been investigated and compared with that of a commercial AZ31 Mg alloy with a similar chemical composition.In vitro tests indicated that the experimental alloy is>2.5 times more resistant to degradation than AZ31 during immersion in HBSS at 37℃ for 72 h.In vivo tests in the femoral vein of a mouse confirmed that the former degrades much more slowly and uniformly in the biological environment than the latter.Compared with WE43 and JDBM alloys,which are currently considered promising candidates for Mg-based biodegradable materials,the experimental alloy in this study showed better degradation resistance with a similar level of biocompatibility.Microstructural and electrochemical factors affecting the degradation behavior of the alloys in this study are also discussed.展开更多
Bisphenol A(BPA)has threatened ecological safety and human health due to its endocrine disrupting effect and widely diffused in the environment.Peroxymonosulfate(PMS)based on oxidation technology exhibits good potenti...Bisphenol A(BPA)has threatened ecological safety and human health due to its endocrine disrupting effect and widely diffused in the environment.Peroxymonosulfate(PMS)based on oxidation technology exhibits good potential for environmental remediation whereas the highly efficient activator needs to be developed.Herein,the Bi OBr(BOB)was synthesized to efficiently activate PMS to remove 95.6%of BPA within 60 min.The observed rate constant of BPA removal in BOB/PMS system is 0.049 min^(-1),which is 60 and 148 times to that of the BOB and PMS processes separately and 129 times to the compared Bi OCl(BOC)/PMS system,respectively.Comparison experiments and analytic methods demonstrate that BOB with a larger content of oxygen vacancies(Ov)can act as the bridge of electron transfer between Bi^(3+)/Bi^(4+)with PMS to enhance the activation ability for PMS,resulting in the production of abundant reactive oxygen species(O_(2)^(·-)and ^(1)O_(2)).Additionally,the breakdown processes of BPA and the toxicity of its byproducts were uncovered,and the potential for actual water treatment was evaluated to confirm the detoxification,efficiency,stability and practical use of the BOB/PMS system for eliminating BPA.This study may widen the application of traditional semiconductors and develop the cost-effective PMS activation methods for environmental remediation.展开更多
基金supported by the National Key R&D Program of China(No.2022YFC3901800)the National Natural Science Foundation of China(No.22176041)Guangzhou Science and Technology Planning Project(No.2023A04J0918)。
文摘Poly(butylene adipate-terephthalate)(PBAT),as one of the most common and promising biodegradable plastics,has been widely used in agriculture,packaging,and other industries due to its strong biodegradability properties.It is well known that PBAT suffers a series of natural weathering,mechanical wear,hydrolysis,photochemical transformation,and other abiotic degradation processes before being biodegraded.Therefore,it is particularly important to understand the role of abiotic degradation in the life cycle of PBAT.Since the abiotic degradation of PBAT has not been systematically summarized,this review aims to summarize the mechanisms and main factors of the three major abiotic degradation pathways(hydrolysis,photochemical transformation,and thermochemical degradation)of PBAT.It was found that all of them preferentially destroy the chemical bonds with higher energy(especially C-O and C=O)of PBAT,which eventually leads to the shortening of the polymer chain and then leads to reduction in molecular weight.The main factors affecting these abiotic degradations are closely related to the energy or PBAT structure.These findings provide important theoretical and practical guidance for identifying effective methods for PBAT waste management and proposing advanced schemes to regulate the degradation rate of PBAT.
基金supported by Fujian Provincial Natural Science Foundation of China(Nos.2023J01456 and 2021J01626)the National Natural Science Foundation of China(No.41976042)the Oceanic Interdisciplinary Program of Shanghai Jiao Tong University(Nos.SL2022ZD207 and SL2023MS019).
文摘Dissolved organic matter(DOM)is very important in aquatic environments,yet it is challenging to characterize DOM as a highly complex mixture of thousands of molecules,and the knowledge of the effects of different degradation processes on different molecules remains limited.This study examined the distribution and degradation of DOM in a large subtropical river using optical techniques and Fourier transform ion cyclotron resonance mass spectrometry(FT-ICR-MS).At the molecular level,DOM was mainly composed of CHO and lignin-like compounds,which was related to the dominance of forestland in the watershed and resulted in a low biological lability index(MLBL).The modified aromaticity index(AI_(mod)),unsaturation degree(DBE),and humic content(HIX)decreased while MLBL,H/C,absorption spectral slope(S_(275–295)),and biological index(BIX)increased in the estuarine zone due to the increasing autochthonous contribution.Photo-and microbial degradation resulted in a similar decrease in the bulk dissolved organic carbon,while they showed opposite effects on the DOM composition.Photo-degradation removed all fluorescent components and decreased molecular weight,HIX,AI_(mod),DBE,%CHO,%lignin-like,%tannin-like,and%condensed aromatic-like compounds.In contrast,bio-degradation preferentially consumed lipid-like,protein-like,and carbohydrate-like compounds,with increases in%ligninlike,%tannin-like,%condensed aromatic-like compounds,and humic-like fluorescent components.Overall,the application of ultra-high resolutionmass spectrometry provided valuable insights into the composition and behavior of DOM at themolecular level and revealed the contrasting effects of photo-and microbial degradation on different compounds.These results have implications for better understanding the composition and transformation of aquatic DOM.
基金financial support of this paper by the Ministry of Education and Science of Ukraine under grant(Biotherm/0124U000789).
文摘The selection of carbon sources and the biosynthesis of polyhydroxybutyrate(PHB)by the Azotobacter vinelandii N-15 strain using renewable raw materials were investigated.Among the tested substrates(starch,sucrose,molasses,bran),molasses as the carbon source yielded the highest PHB production.The maximum polymer yield(26%of dry biomass)was achieved at a molasses concentration of 40 g/L.PHB formation was confirmed via thinlayer chromatography,gas chromatography and Fourier transform infrared spectroscopy.Composite films based on PHB,polylactic acid(PLA),and their blends were fabricated using the solvent casting.The biodegradation of these films was studied with bacteria isolated from plastic-contaminated soil.These bacteria utilized the biopolymers as their sole carbon source,with the biodegradation process lasting three months.Structural and chemical changes in the films were analyzed using FTIR spectroscopy,differential scanning calorimetry,and thermogravimetry.Among the microorganisms used to study the biodegradation of PHB,PLA,and their blends,Streptomyces sp.K2 and Streptomyces sp.K4 exhibited the highest biodegradation efficiency.PHB-containing films demonstrated significant advantages over other biodegradable polymers,as they degrade under aerobic conditions via enzymatic hydrolysis using microbial depolymerases.
基金The financial support from Project(Grant Nos.52278432,and 52168066)of National Natural Science Foundation of China and Project(Grant No.K2023G033)of the Science and Technology Research and Development Plan of China National Railway Group Co.,Ltd.were greatly appreciated.
文摘This paper presents a multi-scale experimental investigation of the weathering degradation of red mudstone.Natural rocks were extracted from the surface ground to 120 m,inwhich three sets of samples were selected to consider the different initial rock fabrics.The long-term relative humidity(RH)cycles under two amplitudes were imposed on red mudstone to simulate the weathering process.After RH cycles,a series of uniaxial compression tests,Brazilian splitting tests and bender-extender element tests were carried out to examine the reduction in strength and stiffness.The objective of this study is to develop an extended stress-volume framework characterizing the degradation of natural red mudstone both at microscale and macroscale.Accompanied by the irreversible swelling of the rock specimen is the progressive degradation of strength,stiffness and Poisson's ratio.A unified exponential degradation model in terms of the irreversible volumetric strain was thus proposed to capture such a degradation pattern.The effect of the initial rock fabric was evident.The highest degradation rate and potential were identified in slightly weathered specimens.Significant slaking of aggregates and crack propagation were confirmed by scanning electron microscope(SEM)micrographs,which were considered as the main consequence of structure damage leading to degradation of mechanical properties.The structure damage during RH cycles denoted the hysteresis nature in the response to the cycling hydraulic reaction,in turn causing the increase in volumetric strain.Thus,the stress-volume relation rather than the suction relation was found in more reasonable agreement with the experimental results.
基金financially supported by the National Natural Science Foundation of China(No.22176041,T2421005)National Key R&D Program of China(No.2022YFC3901800)+1 种基金the Fundamental Research Funds for the Central Universities(No.2243200011)Guangzhou Science and Technology Planning Project(No.2023A04J0918).
文摘Wide bandgap semiconductors are typically activated under ultraviolet(UV)light irradiation for volatile organic compounds(VOCs)degradation.However,our previous study discovered that certain VOCs can interact with some wide bandgap semiconductors,formatting an intermediate bandgap between the VOCs and the conduction band of wide bandgap semiconductor,thus inducing visible light activation of the system,and photo-generated electrons are excited by visible light and transferred from the VOCs to the conduction band of semiconductor.In this work,BaTiO_(3),traditionally is not active under visible light irradiation,however showed degradation rates of 100%and 20%for styrene and toluene under visible light,respectively.Density functional theory(DFT)calculations indicate that the adsorption of styrene or toluene on the BaTiO_(3)surface reduces its bandgap from 2.93 eV to 1.36 eV and 2.26 eV,respectively.The intermediate bandgap in this system is primarily formed by the valence band of BaTiO_(3)and the VOCs,and indicating that photo-generated electrons directly transfer from BaTiO_(3)to the VOCs under visible light,inducing degradation reactions of VOCs,i.e.,this work discovered a new transfer pathway of photo-electrons direct from the valence band of BaTiO_(3)to VOCs,while photo-electrons are from VOCs to the conductive band of wide-bandgap semiconductors in our previous work.
基金supported by the National Natural Science Foundation of China(Nos.52070103 and 22102102)Zhejiang Provincial Natural Science Foundation of China(Nos.LY21E090004 and LQ22B050004)+1 种基金Ningbo Public Welfare Science and Technology Program(No.2021S025)Ningbo Youth Leading Talent Project(No.2024QL038).
文摘Exploration of stable metal single-site supported porous graphitic carbon nitride(PCN)nanostructures and the development of maximum atom utilization for enhanced photocatalytic oxidation of antibiotics remains a challenge in current research.This work proposed a one-step thermal copolymerization to obtain Cu(Ⅰ)doping porous carbon nitride(CUCN)through a spontaneously reducing atmosphere by urea in a covered crucible.The obtained CUCN had crumpled ultrathin nanosheets and mesoporous structures,which possessed higher specific surface areas than PCN.From X-ray absorption near edge structure(XANES)and Fourier transform extended X-ray absorption fine structure(FT-EXAFS)spectra analysis,the Cu doping existed in the oxidation state of Cu(Ⅰ)as single atoms anchored on the 2D layers of CN through two N neighbors,thereby facilitating efficient pathways for the transfer of photoexcited charge carriers.Furthermore,the photoluminescence(PL)spectra,electrochemical impedance spectra(EIS)and transient photocurrent response test proved the improved separation and transfer of photoexcited charge carriers for Cu(Ⅰ)introduction.Consequently,the photocatalytic activity of CUCN was much better than that of PCN for antibiotics norfloxacin(NOR),with 4.7-fold higher degradation reaction rate constants.From species-trapping experiments and density function theory(DFT)calculations,the Cu single atoms in Cu-N_(2)served as catalytic sites that could accelerate charge transfer and facilitate the adsorption of molecular oxygen to produce active species.The stable Cu(Ⅰ)embedded in the layer structure led to the excellent recycling test and remained stable after four runs of degradation and even thermal regenerated treatment.The degradation paths of NOR by CUCN under visible light were also demonstrated.Our work sheds light on a sustainable and practical approach for achieving stable metal single-atom doping and enhancing photocatalytic degradation of aqueous pollutants.
基金Supported by the Research on Biofermentation Technology of Domestic Cigar Tobacco(202115010534-JS-178)(2021)。
文摘Nicotine,also known as nicotinic norephedrine,is one of the main alkaloids present in tobacco plants.In recent years,due to the increase in tobacco production and smoking population,the environmental and health issues caused by nicotine have become increasingly severe.Traditional methods have proven ineffective in efficiently degrading residual nicotine.To address this issue,scientists both domestically and internationally have turned to biodegradation methods to tackle the environmental and health problems caused by residual nicotine.In this study,an enrichment method was used to screen bacteria with nicotine-degrading capabilities from the soil of tobacco planting sites at the Tobacco Research Institute of Heilongjiang in Bin County,Harbin City.Through phenotypic observations and 16S rDNA identification,a bacterial strain identified as Pseudomonas hunanensis MGJ-2 was isolated,capable of utilizing nicotine as a carbon and nitrogen source for growth.High-performance liquid chromatography(HPLC)-1 analysis revealed that within 25 h,strain MGJ-2 could degrade nicotine 500 mg·L^(-1) with an efficiency exceeding 99.9%.Strain MGJ-2 was applied to tobacco,and after 15 days of incubation and fermentation,it degraded 10.57%of nicotine in tobacco.Overall,the discovery of strain MGJ-2 enriched the resources of nicotine-degrading strains.Its remarkable biodegradation performance held immense potential for future biodegradation of nicotine in tobacco.
文摘BACKGROUND Gastric cancer(GC)is a prevalent malignancy with a substantial health burden and high mortality rate,despite advances in prevention,early detection,and treatment.Compared with the global average,Asia,notably China,reports disproportionately high GC incidences.The disease often progresses asymptoma-tically in the early stages,leading to delayed diagnosis and compromised out-comes.Thus,it is crucial to identify early diagnostic biomarkers and enhance treatment strategies to improve patient outcomes and reduce mortality.METHODS Retrospectively analyzed the clinical data of 148 patients with GC treated at the Civil Aviation Shanghai Hospital between December 2022 and December 2023.The associations of coagulation indices-partial thromboplastin time(APTT),prothrombin time(PT),thrombin time(TT),fibrinogen,fibrinogen degradation products(FDP),fasting blood glucose,and D-dimer(D-D)with TNM stage and distant metastasis were examined.RESULTS Prolongation of APTT,PT,and TT was significantly correlated with the GC TNM stage.Hence,abnormal coagulation system activation was closely related to disease progression.Elevated FDP and D-D were significantly associated with distant metastasis in GC(P<0.05),suggesting that increased fibrinolytic activity contributes to increased metastatic risk.CONCLUSION Our Results reveal coagulation indices,FDPs as GC biomarkers,reflecting abnormal coagulation/fibrinolysis,aiding disease progression,metastasis prediction,and helping clinicians assess thrombotic risk for early intervention and personalized treatment plans.
基金financially supported by the National Key Research and Development Program of China(2023YFB3809300)。
文摘With the approaching of large-scale retirement of power lithium-ion batteries(LIBs),their urgent handling is required for environmental protection and resource reutilization.However,at present,substantial spent power batteries,especially for those high recovery value cathode materials,have not been greenly,sustainably,and efficiently recycled.Compared to the traditional recovery method for cathode materials with high energy consumption and severe secondary pollution,the direct repair regeneration,as a new type of short-process and efficient treatment methods,has attracted widespread attention.However,it still faces challenges in homogenization repair,electrochemical performance decline,and scaling-up production.To promote the direct regeneration technology development of failed NCM materials,herein we deeply discuss the failure mechanism of nickel-cobalt-manganese(NCM)ternary cathode materials,including element loss,Li/Ni mixing,phase transformation,structural defects,oxygen release,and surface degradation and reconstruction.Based on this,the detailed analysis and summary of the direct regeneration method embracing solid-phase sintering,eutectic salt assistance,solvothermal synthesis,sol-gel process,spray drying,and redox mediation are provided.Further,the upcycling strategy for regeneration materials,such as single-crystallization and high-nickelization,structural regulation,ion doping,and surface engineering,are discussed in deep.Finally,the challenges faced by the direct regeneration and corresponding countermeasures are pointed out.Undoubtedly,this review provides valuable guidance for the efficient and high-value recovery of failed cathode materials.
基金supported by the National Natural Science Foundation of China(Nos.U20A20274 and 52061003)the Natural Science Foundation of Yunnan Province(No.202301AT070209)the Science and Technology Major Project of Yunnan Province(No.202102AG050017).
文摘In this paper,the property degradation micromechanism of Al-5.10Cu-0.65 Mg-0.8Mn(wt%)alloy induced by 0.5 wt%Fe minor addition was revealed by atomic-scale scanning transmission electron microscopy and energy-dispersive X-ray spectroscopy coupled with first-principles calculations.The results show that the Fe minor addition to the Al-Cu-Mg-Mn alloy leads to a slight reduction of grain size and the formation of coarse Al7Cu2Fe constituent particles.Fe tends to segregate into the T-phase dispersoids,θ'-,and S-phase precipitates by preferentially occupying Cu or Mn sites in these phase structures.The apparent Fe segregation contributes to an increase in stiffness of the T-phase and S-phase but decreased stiffness of theθ'phase.Formation of the coarse Al7Cu2Fe constituent particles and decreased stiffness of main precipitatesθ'containing Fe result in the degraded strength of the Al-Cu-Mg-Mn-Fe alloy.Further study reveals that corrosion resistance degradation of the Al-Cu-Mg-Mn-Fe alloy is associated with the increased width of precipitation free zones and consecutive grain boundary precipitates.The obtained results have significant implications for the usage of recycled Al alloys and the potential design strategies of high-performance alloys containing Fe.
基金financially supported by the National Natural Science Foundation of China(Grant Nos.31830071,32202561)the earmarked fund for CARS(Grant No.CARS-31)。
文摘Banana fruit ripening is a highly regulatory process involving various layers consisting of transcriptional regulation,epigenetic factor,and post-translational modification.Previously,we reported that MaERF11 cooperated with MaHDA1 to precisely regulate the transcription of ripening-associated genes via histone deacetylation.However,whether MaERF11 is subjected to post-translational modification during banana ripening is largely unknown.In this study,we found that MaERF11 targeted a subset of starch degradation-related genes using the DNA affinity purification sequence(DAP-Seq)approach.Electrophoretic mobility shift assay(EMSA)and dual-luciferase reporter assay(DLR)demonstrated that MaERF11 could specifically bind and repress the expression of the starch degradation-related genes MaAMY3,MaBAM2 and MaGWD1.Further analyses of yeast two-hybrid(Y2H),bimolecular fluorescence complementation(BiFC)and Luciferase complementation imaging(LCI)assays indicated that MaERF11 interacted with the ubiquitin E3 ligase MaRFA1,and this interaction weakened the MaERF11-mediated transcriptional repression capacity.Collectively,our results suggest an additional regulatory layer in which MaERF11 regulates banana fruit ripening and expands the regulatory network in fruit ripening at the post-translational modification level.
文摘At present,carbon capture and storage(CCS)is the only mature and commercialized technology capable of effectively and economically reducing greenhouse gas emissions to achieve a significant and immedi-ate impact on the CO_(2) level on Earth.Notably,long-term geological storage of captured CO_(2) has emerged as a primary storage method,given its minimal impact on surface ecological environments and high level of safety.The integrity of CO_(2) storage wellbores can be compromised by the corrosion of steel casings and degradation of cement in supercritical CO_(2) storage environments,potentially leading to the leakage of stored CO_(2) from the sites.This critical review endeavors to establish a knowledge foundation for the cor-rosion and materials degradation associated with geological CO_(2) storage through an in-depth examina-tion and analysis of the environments,operation,and the state-of-the-art progress in research pertaining to the topic.This article discusses the physical and chemical properties of CO_(2) in its supercrit-ical phase during injection and storage.It then introduces the principle of geological CO_(2) storage,consid-erations in the construction of storage systems,and the unique geo-bio-chemical environment involving aqueous media and microbial communities in CO_(2) storage.After a comprehensive analysis of existing knowledge on corrosion in CO_(2) storage,including corrosion mechanisms,parametric effects,and corro-sion rate measurements,this review identifies technical gaps and puts forward potential avenues for fur-ther research in steel corrosion within geological CO_(2) storage systems.
基金Financial support from the National Natural Science Foundation of China(51972016)the Fundamental Research Funds for the Central Universities(JD2417)is gratefully acknowledged.
文摘Although solar steam generation strategy is efficient in desalinating seawater,it is still challenging to achieve continuous solar-thermal desalination of seawater and catalytic degradation of organic pollutants.Herein,dynamic regulations of hydrogen bonding networks and solvation structures are realized by designing an asymmetric bilayer membrane consisting of a bacterial cellulose/carbon nanotube/Co_(2)(OH)_(2)CO_(3)nanorod top layer and a bacterial cellulose/Co_(2)(OH)_(2)CO_(3)nanorod(BCH)bottom layer.Crucially,the hydrogen bonding networks inside the membrane can be tuned by the rich surface–OH groups of the bacterial cellulose and Co_(2)(OH)_(2)CO_(3)as well as the ions and radicals in situ generated during the catalysis process.Moreover,both SO_(4)^(2−)and HSO_(5)−can regulate the solvation structure of Na^(+)and be adsorbed more preferentially on the evaporation surface than Cl^(−),thus hindering the de-solvation of the solvated Na^(+)and subsequent nucleation/growth of NaCl.Furthermore,the heat generated by the solar-thermal energy conversion can accelerate the reaction kinetics and enhance the catalytic degradation efficiency.This work provides a flow-bed water purification system with an asymmetric solar-thermal and catalytic membrane for synergistic solar thermal desalination of seawater/brine and catalytic degradation of organic pollutants.
基金financially supported by the National Natural Science Foundation of China(No.22272151)Public Welfare Technology Application Research Project of Jinhua City,China(No.2023-4-022)。
文摘BiVO_(4)porous spheres modified by ZnO were designed and synthesized using a facile two-step method.The resulting ZnO/BiVO_(4)composite catalysts have shown remarkable efficiency as piezoelectric catalysts for degrading Rhodamine B(RhB)unde mechanical vibrations,they exhibit superior activity compared to pure ZnO.The 40wt%ZnO/BiVO_(4)heterojunction composite displayed the highest activity,along with good stability and recyclability.The enhanced piezoelectric catalytic activity can be attributed to the form ation of an I-scheme heterojunction structure,which can effectively inhibit the electron-hole recombination.Furthermore,hole(h+)and superoxide radical(·O_(2)^(-))are proved to be the primary active species.Therefore,ZnO/BiVO_(4)stands as an efficient and stable piezoelectric catalyst with broad potential application in the field of environmental water pollution treatment.
基金National Natural Science Foundation of China(52072336,51902285)Zhejiang Provincial Natural Science Foundation(LR23E020002)+1 种基金Fundamental Research Funds for the Central Universities(226-2023-00064,226-2024-00146)Shanxi-Zheda Institute of Advanced Materials and Chemical Engineering(2022SZ-FR001)。
文摘Graphdiyne(GDY)and its derivatives have been considered ideal supporting materials for nanoscale active particles because of their unique atomic and electronic structure.An efficient bi-metal Cu-Pd catalyst was added to produce the uniform deposition of Pd nano-clusters with an average size of~0.95 nm on hydrogen-substituted GDY(HGDY)nanosheets.With the assistance of NaBH4,the resulting Pd/H-GDY was very effective in the degradation of 4-nitrophenol(4-NP),whose conversion was sharply increased to 97.21%in 100 s with a rate constant per unit mass(k`)of 8.97×10^(5)min−1 g^(−1).Additionally,dyes such as methyl orange(MO)and Congo red(CR)were completely degraded within 180 and 90 s,respectively.The Pd/H-GDY maintained this activity after 5 reduction cycles.These results highlight the promising performance of Pd/H-GDY in catalyzing the degradation of various pollutants,which is attributed to the combined effect of the largeπ-conjugated structure of the H-GDY nanosheets and the evenly distributed Pd nanoclusters.
基金supported by the National Natural Science Foundation of China(No.42077120)the Special Foundation for Taishan Scholar of Shandong Province(2023)the Project of Talent Introduction and Education Program of Youth Innovation Teams in Universities of Shandong Province(No.2021-05).
文摘Microplastics(MPs) are an emerging environmental pollutant and have penetrated the most remote and primitive areas. MPs degradation has received widespread attention. Manganese(Mn) is a highly reactive metal element in the environment, yet its contribution to MPs degradation remains unclear. Herein,we simulated the aging of polyethylene MPs with Mn(Ⅱ) under aqueous conditions at pH 5 and 8 for720 days. Mn greatly promoted the MPs degradation, and the average particle sizes of polyethylene MPs were reduced from 9.2 μm to 5.9 μm after aging at pH 5 under light irradiation for 720 days. Plenty of oxygen-containing groups were generated on the MPs surfaces, and the carbonyl index remarkably increased, reaching four times that of the control without adding Mn. Mechanistically, the adsorbed Mn(Ⅱ)on the MPs surfaces were primarily oxidized to high-valence Mn(Ⅲ/Ⅳ) profited from the photoproduced radicals, followed by the MPs oxidation via Mn(Ⅲ/Ⅳ), which were reduced to regenerate Mn(Ⅱ), initiating a new redox cycling. During the degradation, dissolved organic matter was continuously released, mainly including bisphenol A and phthalic acid esters. Mn acts as a catalyst to accelerate the MPs degradation by redox cycling. Our results provide a new insight into the mechanisms of abiotic degradation of MPs in aqueous environments.
基金supported by the Key Research and Development Program of Shaanxi Province(No.2024SF-YBXM-567)the National Natural Science Foundation of China(Nos.21976045,22076112)the China Scholarship Council(CSC)Scholarship(No.202308610123).
文摘As antibiotic pollutants cannot be incompletely removed by conventional wastewater treatment plants,ultraviolet(UV)based advanced oxidation processes(AOPs)such as UV/persulfate(UV/PS)and UV/chlorine are increasingly concerned for the effective removal of antibiotics from wastewaters.However,the specific mechanisms involving degradation kinetics and transformation mechanisms are not well elucidated.Here we report a detailed examination of SO_(4)•−/Cl•-mediated degradation kinetics,products,and toxicities of sulfathiazole(ST),sarafloxacin(SAR),and lomefloxacin(LOM)in the two processes.Both SO_(4)•−/Cl•-mediated transformation kinetics were found to be dependent on pH(P<0.05),which was attributed to the disparate reactivities of their individual dissociated forms.Based on competition kinetic experiments and matrix calculations,the cationic forms(H_(2)ST^(+),H_(2)SAR^(+),and H_(2)LOM^(+))were more highly reactive towards SO_(4)•−in most cases,while the neutral forms(e.g.,HSAR^(0)and HLOM^(0))reacted the fastest with Cl•for the most of the antibiotics tested.Based on the identification of 31 key intermediates using tandem mass spectrometry,these reactions generated different products,of which the majority still retained the core chemical structure of the parent compounds.The corresponding diverse transformation pathways were proposed,involving S−N breaking,hydroxylation,defluorination,and chlorination reactions.Furthermore,the toxicity changes of their reaction solutions as well as the toxicity of each intermediate were evaluated by the vibrio fischeri and ECOSAR model,respectively.Many primary by-products were proven to be more toxic than the parent chemicals,raising the wider issue of extended potency for these compounds with regards to their ecotoxicity.These results have implications for assessing the degradative fate and risk of these chemicals during the AOPs.
基金supported in part by the National Research Foundation of Korea(NRF)grant funded by the Korean government(MSIT)(No.2022R1A2C 4001255)。
文摘Through quenching and tempering(QT)and quenching and partitioning(Q&P)processes,this study aimed to investigate the effects of microstructural modifications on the corrosion behavior and corrosion-assisted mechanical degradation of medium Ni-bearing steel.The primary objective was the identification of strategies for the enhancement of the long-term lifespan and reliability of these alloys in neutral aqueous environments.Various electrochemical evaluations and microstructural characterizations were conducted to elucidate the relationship between heat treatment processes and corrosion behavior.The findings reveal that the conventional Q&P process formed partitioned austenite with a coarse size within the martensitic matrix,which led to an uneven distribution of Ni and high kernel average misorientation and resulted in an increased susceptibility to corrosion and corrosion-induced mechanical degradation.In addition,the corroded QT sample displayed preferential attacks around cementite clusters due to selective dissolution.By contrast,a slightly higher partitioning temperature,just above the martensite transformation start temperature,provided finely distributed austenite within bainite in the microstructure,which exhibited lower corrosion kinetics and reduced susceptibility to mechanical degradation in the corrosive environment.This study highlights the potential of microstructural optimization through the Q&P process with a high partitioning temperature as an effective technical strategy for achieving the superior durability and reliability of medium Ni-bearing steel alloys in neutral aqueous environments.
基金supported by the National Research Foundation of Korea(NRF)grant funded by the Korean government(MSIT)(No.RS-2023-00208762)the Ulsan University Hospital Research Grant(UUH-2020-01)the 2025 Research Fund(1.250008.01)of UNIST(Ulsan National Institute of Science and Technology)。
文摘The in vitro and in vivo degradation behavior of an experimental Mg alloy with high corrosion resistance has been investigated and compared with that of a commercial AZ31 Mg alloy with a similar chemical composition.In vitro tests indicated that the experimental alloy is>2.5 times more resistant to degradation than AZ31 during immersion in HBSS at 37℃ for 72 h.In vivo tests in the femoral vein of a mouse confirmed that the former degrades much more slowly and uniformly in the biological environment than the latter.Compared with WE43 and JDBM alloys,which are currently considered promising candidates for Mg-based biodegradable materials,the experimental alloy in this study showed better degradation resistance with a similar level of biocompatibility.Microstructural and electrochemical factors affecting the degradation behavior of the alloys in this study are also discussed.
基金financially supported by the National Key Research and Development Program of China(No.2022YFC3703103)National Natural Science Foundation of China(Nos.22206053,42277427)the Guangzhou Science and Technology Plan Project(No.2024A04J4058)。
文摘Bisphenol A(BPA)has threatened ecological safety and human health due to its endocrine disrupting effect and widely diffused in the environment.Peroxymonosulfate(PMS)based on oxidation technology exhibits good potential for environmental remediation whereas the highly efficient activator needs to be developed.Herein,the Bi OBr(BOB)was synthesized to efficiently activate PMS to remove 95.6%of BPA within 60 min.The observed rate constant of BPA removal in BOB/PMS system is 0.049 min^(-1),which is 60 and 148 times to that of the BOB and PMS processes separately and 129 times to the compared Bi OCl(BOC)/PMS system,respectively.Comparison experiments and analytic methods demonstrate that BOB with a larger content of oxygen vacancies(Ov)can act as the bridge of electron transfer between Bi^(3+)/Bi^(4+)with PMS to enhance the activation ability for PMS,resulting in the production of abundant reactive oxygen species(O_(2)^(·-)and ^(1)O_(2)).Additionally,the breakdown processes of BPA and the toxicity of its byproducts were uncovered,and the potential for actual water treatment was evaluated to confirm the detoxification,efficiency,stability and practical use of the BOB/PMS system for eliminating BPA.This study may widen the application of traditional semiconductors and develop the cost-effective PMS activation methods for environmental remediation.
