Porous liquids(PLs),an emerging porous material with permanent cavities,have attracted extensive attention in recent years.However,the current construction methods are complicated and resulting PLs possess high viscos...Porous liquids(PLs),an emerging porous material with permanent cavities,have attracted extensive attention in recent years.However,the current construction methods are complicated and resulting PLs possess high viscosity values,which cannot meet the requirements of practical industrial applications.Herein,we demonstrate a generalizable and simple strategy to prepare type III PLs with low viscosity based on the rule of“like dissolves like”.Specifically,the monoglycidyl ether terminated polydimethylsiloxane(denoted by E-PDMS)is attached to the surface of Universitetet i Oslo(UiO)-66-NH_(2)via covalent linkage,constructing the pore generator(UiO-66-NH_(2)-E-PDMS,denoted by P-UiO-66).Then,P-UiO-66 is dispersed into different types and amounts of sterically hindered solvents(PDMS400 or PDMS6000),obtaining a series of type III PLs(denoted by P-UiO-66-PLs)with permanent cavities and low viscosities.The gas sorption-desorption test shows that P-UiO-66-PLs have an enormous potential for CO_(2)/N_(2) selective separation.Besides,the porosity of P-UiO-66-PLs and the CO_(2)sorption mechanism are demonstrated by molecular simulation.Furthermore,the generality of the synthesis strategy is confirmed by the successful construction of PLs using two other amino-metal-organic frameworks(MOFs)(MIL-53(Al)-NH_(2)and MIL-88B(Fe)-NH_(2)).Importantly,it’s worth noting that the strategy based on the rule of“like dissolves like”sheds light on the preparation of other types of PLs for task-specific applications.展开更多
Intense chemical weathering in tropical regions produces soils characterized by silicon(Si)depletion and iron and aluminum oxide accumulation,leading to soil degradation.Consequently,Si cycling is of paramount importa...Intense chemical weathering in tropical regions produces soils characterized by silicon(Si)depletion and iron and aluminum oxide accumulation,leading to soil degradation.Consequently,Si cycling is of paramount importance in tropical regions.This review summarizes the key processes of the terrestrial Si biogeochemical cycle in tropical areas and underscores its biogeochemical significance in ecosystems.Runoff outputs constitute the dominant mechanism of Si depletion in tropical soils.However,the combined effects of dissolved Si(DSi)retention by highly weathered soil and Si uptake by vegetation attenuate desilication rates in these ecosystems.Tropical soils exhibit limited quantities of weatherable minerals,resulting in soil solution with low concentrations of DSi.Consequently,the primary sources of available Si are atmospheric dust inputs from distant sources and biogenic silica originating from plants.Irrigation,application of Si fertilizers,crop harvesting,and corresponding Si exports significantly impact soil Si cycling within agroecosystems.Therefore,soil Si cycling in tropical regions is different from that in other climatic zones.However,there are still many knowledge gaps within contemporary research.We propose to delve into several perspectives,including the exploration of the processes,fluxes,rates,related factors,and mechanisms associated with Si cycling in tropical regions.Comprehensive research from these perspectives would significantly enhance the understanding of pedogenesis and soil evolution and provide valuable insights for guiding the sustainable management of tropical soils.展开更多
Exogenous organic input impacts soil phosphorus transformation.Meanwhile,dissolved organic matter(DOM)is crucial for biogeochemical functions.Nevertheless,the interaction between the structural composition of DOM and ...Exogenous organic input impacts soil phosphorus transformation.Meanwhile,dissolved organic matter(DOM)is crucial for biogeochemical functions.Nevertheless,the interaction between the structural composition of DOM and phosphorus during the soil formation process of phosphogypsum(PG)remains unknown.This study explores the interaction between the structural composition of DOM and phosphorus in enhanced PG under the participation of fungal microorganisms through different application amounts of exogenous organic matter and culture time.Results show that application of exogenous organic matter led to varying degrees of increase in dissolved organic carbon(DOC)concentration and humification extent in the soil-like substrate.Additionally,the relative abundance of protein-like component C3 exhibited a trend of initial increase followed by decline over time.The contents of available phosphorus(AP),microbial biomass phosphorus(MBP),and active phosphorus pools(Active-P)in the soil-like substrate are all enhanced overall.Furthermore,a significant correlation exists between DOC and AP as well as MBP.This suggests that DOM is a crucial factor in enhancing the phosphorus availability of the soil-like substrate.The enrichment of known phosphate-solubilizing fungi in culturing favors the decomposition,activation and utilization of hard-to-mineralize phosphorus components in the soil-like substrate.These findings help understand DOM’s biogeochemical behavior and offer insights into PG utilization and the sustainable development of China’s phosphorus industry.展开更多
The dissolution of iron from the cathode and electrode/electrolyte interface(EEI)during long cycles significantly accelerates the aging process of LiFePO_(4)(LFP)/graphite batteries;there is a lack of systematic under...The dissolution of iron from the cathode and electrode/electrolyte interface(EEI)during long cycles significantly accelerates the aging process of LiFePO_(4)(LFP)/graphite batteries;there is a lack of systematic understanding of the spatial distribution of the EEI interface layer and the dissolve of Fe ions,especially in terms of the mechanism of the cathode-electrolyte interphase(CEI),solid electrolyte interphase(SEI),and iron dissolution.In this study,aged cells were subjected to continuous activation with constant current and multi-step segmented indirect activation(IA)and analyzed for capacity fade,impedance growth,and active Li^(+)mass loss at the EEI and nanoscale levels.The interaction between dissolved Fe^(2+)and the EEI in LFP/graphite pouch batteries was proposed and verified.The findings indicate that during IA process,the electric field facilitates the migration of solvated ions toward the electrodes,while simultaneously inhibiting the formation of organic species such as ROCO_(2)Li.The SEI primarily consists of a mixture of organic and inorganic small molecules,forming a continuous and uniform film on the electrode surface.This study demonstrates that IA favors the formation of a uniform EEI and offers constructive insights for advancing accelerated lifetime prediction strategies in lithium-ion batteries.展开更多
To elucidate the geographical differentiation characteristics and driving mechanisms of Dissolved Organic Matter(DOM)in typical rivers,this study conducted a multi-spectral investigation on three representative river ...To elucidate the geographical differentiation characteristics and driving mechanisms of Dissolved Organic Matter(DOM)in typical rivers,this study conducted a multi-spectral investigation on three representative river types within Shandong Province:The mountainous Dawen River,the plain Tuhai River,and the artificial East Grand Canal.The DOM composition was analyzed using Ultraviolet-Visible(UV-Vis)absorption spectroscopy,Excitation-Emission Matrix(EEM)fluorescence spectroscopy,and parallel factor analysis(PARAFAC),while Principal Component Analysis(PCA)was employed to quantify the synergistic effects of natural processes and anthropogenic activities.Results revealed significant spatial heterogeneity in DOM composition and sources.The plain river exhibited the highest aromaticity(humic-like components:43.3%)due to long-term agricultural non-point source inputs and urban wastewater discharge.The mountain stream,shaped by complex terrain and relatively intact ecosystems,was dominated by autochthonous DOM derived from microbial metabolism,with higher Fluorescence Index(FI=2.12)and biological index(BIX=1.35)than other river types.The artificial canal retained protein-like components(64.2%),largely attributed to winter hydrological stagnation and disturbances from shipping activities.Further analysis demonstrated that geographical settings(e.g.,mountain terrain)and anthropogenic activities(e.g.,agriculture,shipping)jointly regulated DOM composition by altering the balance between input and transformation processes.Integrated fluorescence parameters and PCA results suggested differentiated management strategies:protecting ecological integrity in mountain streams to sustain selfpurification,enhancing non-point source interception in plain rivers,and mitigating shipping pollution in canals.This study systematically reveals the natural-anthropogenic coupling mechanisms driving DOM dynamics in northern China rivers,providing critical insights for precision water environment management at the watershed scale.展开更多
The essential step to improve the coagulation efficiency is to select and optimize the pre-oxidation process.Ultraviolet/sodium percarbonate(UV/SPC)can be employed as an alternative system to UV/H_(2)O_(2) in drinking...The essential step to improve the coagulation efficiency is to select and optimize the pre-oxidation process.Ultraviolet/sodium percarbonate(UV/SPC)can be employed as an alternative system to UV/H_(2)O_(2) in drinking water treatment plant operation,benefiting from the solid stability properties with the equivalent effect.At present,the studies on UV/SPC,and other UV/advanced oxidation processes(UV/H_(2)O_(2),UV/persulfate,UV/chlorine,etc.),mostly focus on the advanced water treatment after filtration.This study notes that UV/SPC has advantages in the pre-oxidized organics.UV/SPC improving the effect of coagulation on dissolved organic carbon(DOC)elimination by up to 25%,the optimal UV dose and SPC dosage are 600 mJ/cm^(2) and 20 mg/L verified by a pilot experiment;the decomposition degree and conversion of organics which is most conducive to follow-up coagulation treatment is obtained through the detailed comparison of the influence range of UV dose or the CSPC on the molecule structure of organics;the disparate role of UV was unraveled in UV photolysis pre-oxidation and UV/SPC pre-oxidation and coagulation,including the influence regularity of UV transmittance(UVT)and processing flow rate on UV dose;confirm that UV/SPC alleviates the risk of the generation of disinfection byproducts(DBPs)to 51.15%.This study corroborates the potential of UV/SPC as a pre-oxidation technology at the application level.展开更多
China’s lakes are plagued by cadmium(Cd)pollution.Dissolved organic matter(DOM)significantly regulates Cd(II)transport properties at the sediment-water interface.Understanding the effects of different DOM components ...China’s lakes are plagued by cadmium(Cd)pollution.Dissolved organic matter(DOM)significantly regulates Cd(II)transport properties at the sediment-water interface.Understanding the effects of different DOM components on the transportation properties of Cd(II)at the sediment-water interface is essential.In this study,typical DOM from different sources was selected to study Cd(II)mobility at the sediment-water interface.Results showed that terrestrial-derived DOM(fulvic acids,FA)and autochthonous-derived DOM(α-amylase,B1)inhibit Cd(II)sequestration by sediments(42.5%and 5.8%,respectively),while anthropogenic-derived DOM(sodium dodecyl benzene sulfonate,SDBS)increased the Cd(II)adsorption capacity by sediments by 2.8%.Fluorescence quenching coupling with parallel factor analysis(EEM-PARAFAC)was used to characterize different DOM components.The results showed that FA contains three kinds of components(C1,C3:protein-like components,C2:humic-like components);SDBS contains two kinds of components(C1,C2:protein-like components);B1 contains three kinds of components(C1,C2:protein-like components,C3:humic-like components).Three complex reaction modelswere used to characterize the ability of Cd(II)complex with DOM,and it was found that the humic-like component could hardly be complex with Cd(II).Accordingly,humic-like components compete for Cd(II)adsorption sites on the sediment surface and inhibit Cd(II)adsorption fromsediments.Fourier transform infrared spectroscopy(FTIR)of the sediment surface before and after Cd(II)addition was analyzed and proved the competitive adsorption theory.This study provides a better understanding of the Cd(II)mobilization behavior at the sediment-water interface and indicates that the input of humic-like DOM will increase the bioavailability of Cd.展开更多
Polybrominated biphenyl ethers(PBDEs)and polycyclic aromatic hydrocarbons(PAHs)are commonly detected contaminants at e-waste recycling sites.Against the conventional wisdom that PBDEs and PAHs are highly immobile and ...Polybrominated biphenyl ethers(PBDEs)and polycyclic aromatic hydrocarbons(PAHs)are commonly detected contaminants at e-waste recycling sites.Against the conventional wisdom that PBDEs and PAHs are highly immobile and persist primarily in shallowsurface soils,increasing evidence shows that these compounds can leach into the groundwater.Herein,we compare the leachabilities of PBDEs vs.PAHs from contaminated soils collected at an e-waste recycling site in Tianjin,China.Considerable amounts of BDE-209(0.3–2 ng/L)and phenanthrene(42–106 ng/L),the most abundant PBDE and PAH at the site,are detected in the effluents of columns packed with contaminated soils,with the specific concentrations varying with hydrodynamic and solution chemistry conditions.Interestingly,the leaching potential of BDE-209 appears to be closely related to the release of colloidal mineral particles,whereas the leachability of phenanthrene correlates well with the concentration of dissolved organic carbon in the effluent,but showing essentially no correlation with the concentration of mineral particles.The surprisingly different trends of the leachability observed between BDE-209 and phenanthrene is counterintuitive,as PBDEs and PAHs often co-exist at e-waste recycling sites(particularly at the sites wherein incineration is being practiced)and share many similarities in terms of physicochemical properties.One possible explanation is that due to its extremely low solubility,BDE-209 predominantly exists in free-phase(i.e.,as solid(nano)particles),whereas the more soluble phenanthrene is mainly sorbed to soil organic matter.Findings in this study underscore the need to better understand the mobility of highly hydrophobic organic contaminants at contaminated sites for improved risk management.展开更多
As a widely used fertilizer,urea significantly promotes the leaching of dissolved organic nitrogen(DON)in soils and aggravates nitrogen contamination in groundwater.Clayminerals are considered the most important facto...As a widely used fertilizer,urea significantly promotes the leaching of dissolved organic nitrogen(DON)in soils and aggravates nitrogen contamination in groundwater.Clayminerals are considered the most important factor in retaining DON.However,the effect of urea on the retention of DON with different molecular weights by clay minerals is unknown.In this study,the retention of both low-molecular weight DON(LMWD)and high-molecular weight DON(HMWD)by clay minerals in the presence of urea was investigated.For this purpose,batch adsorption and soil column leaching experiments,characterization analysis(Fourier transform infrared spectroscopy X-ray diffraction,and X-ray photoelectron spectroscopy),and molecular dynamics simulations were carried out.Urea had a positive effect on the adsorption of LMWD,whereas a competitive effect existed for the adsorption of HMWD.The dominant interactions among DON,urea,and clay minerals included H-bonding,ligand exchange,and cation exchange.The urea was preferentially adsorbed on clay minerals and formed a complex,which provided more adsorption sites to LMWD and only a few to HMWD.The presence of urea increased the retention of LMWD and decreased the retention of HMWD in clay minerals.The retention capacity of LMWD increased by 6.9%–12.8%,while that of HMWD decreased by 6.7%–53.1%.These findings suggest that LMWD tended to be trapped in soils,while HMWD was prone to be leached into groundwater,which can be used to evaluate the leaching of DON from soil to groundwater.展开更多
Cancer vaccines are a notable area of immunotherapy due to their capacity to elicit specific antitumor immune responses and to create immune memory.However,they encounter challenges in clinical practice due to several...Cancer vaccines are a notable area of immunotherapy due to their capacity to elicit specific antitumor immune responses and to create immune memory.However,they encounter challenges in clinical practice due to several bottlenecks,including tumor heterogeneity,low immunogenicity,immunosuppressive tumor environment,and delivery obstacles,which collectively impact their clinical effectiveness.In this study,we developed nanocomposites containing positively charged melittin(MEL)and negatively charged photosensitizer indocyanine green(ICG),embedded in dissolving microneedles(MEL/ICG-HA@DMNs).This approach allows precise drug delivery by creating microchannels that bypass the stratum corneum barrier,targeting superficial lesions directly.Our results demonstrated that the complexation of MEL and ICG significantly reduced the hemolytic activity of MEL while maintaining its ability to disrupt cell membranes.After loading MEL/ICG-HA into the microneedle,MEL/ICG-HA@DMNs not only effectively concentrated the drug at the tumor site,inducing localized hyperthermia and successfully ablating the tumor,but also formed an in situ whole-cell vaccine containing a rich source of tumor-associated antigens.Moreover,the system promoted dendritic cell maturation and increased the M1/M2 macrophage ratio,enhancing the immune response.By overcoming the limitations of traditional cancer vaccines,this system ensures precise drug delivery and robust immune activation.This innovative approach holds the potential to revolutionize cancer treatment,offering a new paradigm in precision oncology.展开更多
Lake Baiyangdian is one of China’s largest macrophyte-derived lakes,facing severe challenges related to water quality maintenance and eutrophication prevention.Dissolved organic matter(DOM)was a huge carbon pool and ...Lake Baiyangdian is one of China’s largest macrophyte-derived lakes,facing severe challenges related to water quality maintenance and eutrophication prevention.Dissolved organic matter(DOM)was a huge carbon pool and its abundance,property,and transformation played important roles in the biogeochemical cycle and energy flow in lake ecosystems.In this study,Lake Baiyangdian was divided into four distinct areas:Unartificial Area(UA),Village Area(VA),Tourism Area(TA),and Breeding Area(BA).We examined the diversity of DOM properties and sources across these functional areas.Our findings reveal that DOM in this lake is predominantly composed of protein-like substances,as determined by excitation-emission matrix and parallel factor analysis(EEM-PARAFAC).Notably,the exogenous tyrosine-like component C1 showed a stronger presence in VA and BA compared to UA and TA.Ultrahigh-resolution mass spectrometry(FT-ICR MS)unveiled a similar DOM molecular composition pattern across different functional areas due to the high relative abundances of lignan compounds,suggesting that macrophytes significantly influence the material structure of DOM.DOM properties exhibited specific associations with water quality indicators in various functional areas,as indicated by the Mantel test.The connections between DOM properties and NO_(3)-N andNH3-Nwere more pronounced in VA and BA than in UA and TA.Our results underscore the viability of using DOM as an indicator for more precise and scientific water quality management.展开更多
The dissolved organic matter(DOM)with high mobility and reactivity plays a crucial role in soil.In this study,the characteristics and phytotoxicity ofDOMreleased fromthe hydrochars prepared from different feedstocks(c...The dissolved organic matter(DOM)with high mobility and reactivity plays a crucial role in soil.In this study,the characteristics and phytotoxicity ofDOMreleased fromthe hydrochars prepared from different feedstocks(cowmanure,corn stalk and Myriophyllum aquaticum)under three hydrothermal carbonization(HTC)temperatures(180,200 and 220°C)were evaluated.The results showed that the hydrochars had high dissolved organic carbon content(20.15 to 37.65 mg/g)and its content showed a gradual reduction as HTC temperature increased.Three fluorescent components including mixed substance of fulvic acid-like and humic acid-like substances(C1,30.92%-58.32%),UVA humic acid-like substance(C2,25.27%-29.94%)and protein-like substance(C3,11.74%-41.92%)were identified in hydrochar DOM by excitation emission matrix spectra coupled with parallel factor analysis.High HTC temperature increased the relative proportion of aromatic substances(C1+C2)and humification degree of hydrochar DOM from cow manure,while it presented adverse effects on the hydrochar DOM from corn stalk and Myriophyllum.aquaticum.The principal component analysis suggested that feedstock type and HTC temperature posed significant effects on the characteristics of hydrochar DOM.Additionally,seed germination test of all hydrochar DOM demonstrated that the root length was reduced by 8.88%-26.43%in contrast with control,and the germination index values were 73.57%-91.12%.These findings provided new insights into the potential environmental effects for hydrochar application in soil.展开更多
Dissolved organic carbon(DOC)constitutes the largest organic carbon reservoir in the ocean and plays a vital role in the oceanic carbon cycle.However,research on DOC in Antarctica has been limited,largely due to diffi...Dissolved organic carbon(DOC)constitutes the largest organic carbon reservoir in the ocean and plays a vital role in the oceanic carbon cycle.However,research on DOC in Antarctica has been limited,largely due to difficulties in sample collection.In this study,we investigate chromophoric dissolved organic matter(CDOM)in the Cosmonaut Sea and Cooperation Sea,Antarctica.The relative abundances of CDOM,as indicated by the absorption coefficient at 254 nm(a_(254)),exhibit significant variability,ranging from 1.29 m^(-1) to 8.37 m^(-1).The diatom species B is the primary contributor to CDOM in the region influenced by the Antarctic slope current.Using excitation-emission matrix fluorescence spectroscopy coupled with parallel factor analysis(EEM-PARAFAC),we identify three fluorescent components:one protein-like component(C1)and two humic-like components(C2 and C3).Our findings indicate that strong microbial activity in the euphotic zones of the Cosmonaut Sea and Cooperation Sea serves as a primary pathway for the removal of protein-like substances while also acting as a significant source of humic-like substances.Microbial degradation likely accounts for the decoupling of the vertical distribution of DOC and phytoplankton.Furthermore,the intrusion of modified circumpolar deep water(mCDW)into the euphotic zones of open ocean areas influences the distribution of CDOM at depths shallower than 200 m.These results have important implications for enhancing our understanding of the dynamics of CDOM and DOC in east Antarctica,as well as for improving assessments of the carbon cycle.展开更多
Arsenic-contaminated groundwater is widely used in agriculture.To meet the increasing demand for safe water in agriculture,an efficient and cost-effective method for As removal from groundwater is urgently needed.We h...Arsenic-contaminated groundwater is widely used in agriculture.To meet the increasing demand for safe water in agriculture,an efficient and cost-effective method for As removal from groundwater is urgently needed.We hypothesized that Fe(oxyhydr)oxide(FeOOH)minerals precipitated in situ from indigenous Fe in groundwater may immobilize As,providing a solution for safely using As-contaminated groundwater in irrigation.To confirm this hypothesis and identify the controlling mechanisms,we comprehensively evaluated the transport,speciation changes,and immobilization of As and Fe in agricultural canals irrigated using As-contaminated groundwater.The efficiently removed As and Fe in the canals accumulated in shallow sediment rather than subsurface sediment.Linear combination fitting(LCF)analysis of X-ray absorption near edge spectroscopy(XANES)indicated that As(Ⅴ)was the dominant As species,followed by As(Ⅲ),and therewas no FeAsO_(4) precipitate.Sequential extraction revealed higher contents of amorphous FeOOH and associated As in shallower sediment than in the subsurface layer.Stoichiometric molar ratio calculations,SEM-EDS,FTIR,and fluorescence spectroscopy collectively demonstrated that the microbial reductive dissolution of amorphous FeOOH proceeded via reactive dissolved organic matter(DOM)consumption in subsurface anoxic porewater environment facilitating high labile As,whereas in surface sediment,the in situ-generated amorphous FeOOH was stable and strongly inhibited As release via adsorption.In summary,groundwater Fe^(2+)can efficiently precipitate in benthic surface sediment as abundant amorphous FeOOH,which immobilizes most of the dissolved As,protecting agricultural soil from contamination.This field research supports the critical roles of the phase and reactivity of in situ-generated FeOOH in As immobilization and provides new insight into the sustainable use of contaminated water.展开更多
Aerated drip irrigation(ADI)is an important practice for promoting soil fertility and crop productivity in greenhouse vegetable production,yet little research has comprehensively investigated its effects on the functi...Aerated drip irrigation(ADI)is an important practice for promoting soil fertility and crop productivity in greenhouse vegetable production,yet little research has comprehensively investigated its effects on the functional traits of carbon(C)-cycling microorganisms.In this study,we sought to assess the potential efficacy of ADI in increasing soil organic C(SOC)by changing soil microbial communities and the expressions of genes associated with C cycling.To this end,we adopted a metagenomic approach to compare the effects of ADI with three dissolved oxygen concentrations(10,15,and 20 mg L^(-1))during a three-season tomato cultivation experiment in northern China.The results revealed that the 10 mg L^(-1)treatment led to a significant increase in the abundance of korA/B genes(associated with the reductive tricarboxylic acid cycle)in the C fixation pathway,whereas the 15 mg L^(-1)treatment increased the abundances of cbbL/R and coxL/S genes associated with the Calvin cycle and carbon monoxide oxidation,respectively.In addition,based on a co-occurrence network analysis,we observed a positive correlation between cbbL and coxS.Interestingly,r-selected microorganisms,such as Proteobacteria and Actinobacteria,characterized by rapid cell multiplication and high biomass production,were identified as the primary contributors to C fixation and were the main predictors of SOC pools.In contrast,the 20 mg L^(-1)treatment was found to adversely influence C fixation,although the enhanced C degradation could be attributed to the extracellular enzymes secreted by K-selected microorganisms.Collectively,our findings indicate that ADI with dissolved oxygen concentrations 15 mg L^(-1)can promote SOC content by altering the life history strategies of r-selected microorganisms and genes associated with C fixation.These findings will provide valuable references for agroecosystem irrigation management,help improve soil fertility,and promote sustainable production.展开更多
The copper complexing of dissolved organic matter released from hydrochar(HDOM)affects the former’s environmental behavior.In this study,how hydrothermal temperatures(180,220 and 260℃)influence the molecular-level c...The copper complexing of dissolved organic matter released from hydrochar(HDOM)affects the former’s environmental behavior.In this study,how hydrothermal temperatures(180,220 and 260℃)influence the molecular-level constitutions and Cu(II)binding features of HDOM were elucidated via fourier transform ion cyclotron resonance mass spectrometry and multi-spectroscopic analysis.The findings demonstrated that the almost HDOM molecules had the traits of lower polarity and higher hydrophobicity.As the hydrothermal temperature increased,the molecules with particularly high relative strength gradually disappeared,average molecular weight,percentages of CHON and aliphatic compounds of HDOM reduced while the percentages of CHO and aromatic compounds increased.In general,the fluorescence quenching of Cu(II)weakened as hydrothermal temperature rose and the Cu(II)binding stability constants of fluorophores in HDOM were 4.50–5.31.In addition,the Cu(II) binding order of fluorophores in HDOM showed temperature heterogeneities, andpolysaccharides or aromatic rings of non-fluorescent substances had the fastest responsesto Cu(II) binding. Generally, fluorescent components tend to bind Cu(II) at relatively traceconcentrations (0–40 μmol/L), whereas non-fluorescent substances tend to the bind Cu(II)at relatively higher concentrations (50–100 μmol/L). This study contributed to the predictionof the potential environmental behaviors and risks of Cu(II) at the molecular level afterhydrochar application.展开更多
Dissolved black carbon(DBC)plays a crucial role in the migration and bioavailability of iron in water.However,the properties of DBC releasing under diverse pyrolysis conditions and dissolving processes have not been s...Dissolved black carbon(DBC)plays a crucial role in the migration and bioavailability of iron in water.However,the properties of DBC releasing under diverse pyrolysis conditions and dissolving processes have not been systematically studied.Here,the compositions of DBC released from biochar through redox processes dominated by bacteria and light were thoroughly studied.It was found that the DBC released from straw biochar possess more oxygen-containing functional groups and aromatic substances.The content of phenolic and carboxylic groups in DBC was increased under influence of microorganisms and light,respectively.The concentration of phenolic hydroxyl groups increased from 10.0~57.5 mmol/gC to 6.6~65.2 mmol/gC,and the concentration of carboxyl groups increased from49.7~97.5 mmol/gC to 62.1~113.3 mmol/gC.Then the impacts of DBC on pyrite dissolution andmicroalgae growth were also investigated.The complexing Fe^(3+)was proved to play a predominant role in the dissolution of ferrous mineral in DBC solution.Due to complexing between iron ion and DBC,the amount of dissolved Fe in aquatic water may rise as a result of elevated number of aromatic components with oxygen containing groups and low molecular weight generated under light conditions.Fe-DBC complexations in solution significantly promoted microalga growth,which might be attributed to the stimulating effect of dissolved Fe on the chlorophyll synthesis.The results of study will deepen our understanding of the behavior and ultimate destiny of DBC released into an iron-rich environment under redox conditions.展开更多
Biochar-derived dissolved organic matter(BCDOM),an essential component of biochar,plays a vital role in regulating the physicochemical and biological properties of soils during biochar application.However,the influenc...Biochar-derived dissolved organic matter(BCDOM),an essential component of biochar,plays a vital role in regulating the physicochemical and biological properties of soils during biochar application.However,the influence of BCDOM on soil organisms has not been clearly explained.Hence,this review aims to discuss the factors affecting BCDOM and its interaction with soil substances including organic pollutants,heavy metals,and microorganisms.Results displayed that the quantity of BCDOM ranges from 0.17 to 37.03 mg/g,which was influenced by feedstock,preparation methods of biochar,and extraction methods.With the decrease in lignin content of feedstocks,carbonization temperature,and acidity of extraction solution,the content of BCDOM increased.Through complexation and adsorption,protein-like components in BCDOM interact with heavy metals,promoting the adsorption and immobilization of heavy metals onto biochar.Furthermore,BCDOM enhances the adsorption of organic pollutants by biochar throughπ−πinteractions,hydrogen bonding,and redox processes.More importantly,BCDOM promotes plant growth by enhancing microbial activities,providing nutrients,and improving soil properties.However,the transport and fate of BCDOM in soil have not been well studied,and more researches are needed to explore the interaction mechanisms between BCDOM and soil organisms.展开更多
Oceanic dissolved oxygen(DO)concentration is crucial for assessing the status of marine ecosystems.Against the backdrop of global warming,DO shows a general decrease,posing a threat to the health of marine ecosystems....Oceanic dissolved oxygen(DO)concentration is crucial for assessing the status of marine ecosystems.Against the backdrop of global warming,DO shows a general decrease,posing a threat to the health of marine ecosystems.Therefore,there is an urgent need to develop advanced tools to characterize the spatio-temporal variations of three-dimensional(3D)DO.To address this challenge,this study introduces the Light Gradient Boosting Machine(Light-GBM),combining satellite remote sensing and reanalysis data with Biogeochemical Argo data to accurately reconstruct the 3D DO structure in the Mediterranean Sea from 2010 to 2022.Various environmental parameters are incorporated as inputs,including spatiotemporal features,meteorological characteristics,and ocean color properties.The LightGBM model demonstrates excellent performance on the testing dataset with R^(2) of 0.958.The modeled DO agrees better with in-situ measurements than products from numerical models.Using the Shapley Additive exPlanations method,the contributions of input features are assessed.Sea surface temperatures provide a correlation with DO at the sea surface,while spatial coordinates supplement the view of the ocean interior.Based on the reconstructed 3D DO structure,we identify an oxygen minimum zone in the western Mediterranean that expands continuously,reaching depths of approximately 300–800 m.The western Mediterranean exhibits a significant declining trend.This study enhances marine environmental evidence by proposing a precise and cost-effective approach for reconstructing 3D DO,thereby offering insights into the dynamics of DO variations under changing climatic conditions.展开更多
The inefficiency of photocatalytic overall water splitting is well documented and has been extensively studied.However,a crucial aspect of this process,the side reaction,has often been overlooked.In this study,we inve...The inefficiency of photocatalytic overall water splitting is well documented and has been extensively studied.However,a crucial aspect of this process,the side reaction,has often been overlooked.In this study,we investigate the impact of side reactions on photocatalytic overall water splitting by monitoring factors such as dissolved oxygen,reactive oxygen species,and hydrogen peroxide.Further insights into the side reaction are obtained through the introduction of a platinum cocatalyst.Our findings reveal that dissolved oxygen significantly contributes to the side reaction by promoting the production of hydrogen peroxide.This byproduct is generated at the expense of electrons needed for the hydrogen evolution reaction,thereby reducing the overall efficiency of photocatalytic water splitting.This article aims to provide guidance on future research directions in the field of water splitting,with a particular emphasis on photocatalysis.展开更多
基金This work is supported by the Aeronautical Science Foundation of China(No.2018ZF53065)the Key Project of Shaanxi Provincial Natural Science Foundation(No.2021JZ-09)+1 种基金the National Undergraduate Training Program for Innovation and Entrepreneurship(No.201910699113)the Shaanxi Province Science Foundation for Youths(No.2023-JC-QN-0146).
文摘Porous liquids(PLs),an emerging porous material with permanent cavities,have attracted extensive attention in recent years.However,the current construction methods are complicated and resulting PLs possess high viscosity values,which cannot meet the requirements of practical industrial applications.Herein,we demonstrate a generalizable and simple strategy to prepare type III PLs with low viscosity based on the rule of“like dissolves like”.Specifically,the monoglycidyl ether terminated polydimethylsiloxane(denoted by E-PDMS)is attached to the surface of Universitetet i Oslo(UiO)-66-NH_(2)via covalent linkage,constructing the pore generator(UiO-66-NH_(2)-E-PDMS,denoted by P-UiO-66).Then,P-UiO-66 is dispersed into different types and amounts of sterically hindered solvents(PDMS400 or PDMS6000),obtaining a series of type III PLs(denoted by P-UiO-66-PLs)with permanent cavities and low viscosities.The gas sorption-desorption test shows that P-UiO-66-PLs have an enormous potential for CO_(2)/N_(2) selective separation.Besides,the porosity of P-UiO-66-PLs and the CO_(2)sorption mechanism are demonstrated by molecular simulation.Furthermore,the generality of the synthesis strategy is confirmed by the successful construction of PLs using two other amino-metal-organic frameworks(MOFs)(MIL-53(Al)-NH_(2)and MIL-88B(Fe)-NH_(2)).Importantly,it’s worth noting that the strategy based on the rule of“like dissolves like”sheds light on the preparation of other types of PLs for task-specific applications.
基金financially supported by the National Natural Science Foundation of China(Nos.42277312 and 41877010)。
文摘Intense chemical weathering in tropical regions produces soils characterized by silicon(Si)depletion and iron and aluminum oxide accumulation,leading to soil degradation.Consequently,Si cycling is of paramount importance in tropical regions.This review summarizes the key processes of the terrestrial Si biogeochemical cycle in tropical areas and underscores its biogeochemical significance in ecosystems.Runoff outputs constitute the dominant mechanism of Si depletion in tropical soils.However,the combined effects of dissolved Si(DSi)retention by highly weathered soil and Si uptake by vegetation attenuate desilication rates in these ecosystems.Tropical soils exhibit limited quantities of weatherable minerals,resulting in soil solution with low concentrations of DSi.Consequently,the primary sources of available Si are atmospheric dust inputs from distant sources and biogenic silica originating from plants.Irrigation,application of Si fertilizers,crop harvesting,and corresponding Si exports significantly impact soil Si cycling within agroecosystems.Therefore,soil Si cycling in tropical regions is different from that in other climatic zones.However,there are still many knowledge gaps within contemporary research.We propose to delve into several perspectives,including the exploration of the processes,fluxes,rates,related factors,and mechanisms associated with Si cycling in tropical regions.Comprehensive research from these perspectives would significantly enhance the understanding of pedogenesis and soil evolution and provide valuable insights for guiding the sustainable management of tropical soils.
基金supported by the Science and Technology Major Program of Yunnan(No.202402AG0500103)the Industrial Innovation Talent Project of Yunnan(No.XDYC-CYCX-2023007)the National Key Research and Development Program of China(No.2023YFC3709100).
文摘Exogenous organic input impacts soil phosphorus transformation.Meanwhile,dissolved organic matter(DOM)is crucial for biogeochemical functions.Nevertheless,the interaction between the structural composition of DOM and phosphorus during the soil formation process of phosphogypsum(PG)remains unknown.This study explores the interaction between the structural composition of DOM and phosphorus in enhanced PG under the participation of fungal microorganisms through different application amounts of exogenous organic matter and culture time.Results show that application of exogenous organic matter led to varying degrees of increase in dissolved organic carbon(DOC)concentration and humification extent in the soil-like substrate.Additionally,the relative abundance of protein-like component C3 exhibited a trend of initial increase followed by decline over time.The contents of available phosphorus(AP),microbial biomass phosphorus(MBP),and active phosphorus pools(Active-P)in the soil-like substrate are all enhanced overall.Furthermore,a significant correlation exists between DOC and AP as well as MBP.This suggests that DOM is a crucial factor in enhancing the phosphorus availability of the soil-like substrate.The enrichment of known phosphate-solubilizing fungi in culturing favors the decomposition,activation and utilization of hard-to-mineralize phosphorus components in the soil-like substrate.These findings help understand DOM’s biogeochemical behavior and offer insights into PG utilization and the sustainable development of China’s phosphorus industry.
基金supported by the National Key R&D Program of China(2021YFB2401800)the support from Beijing Nova Program(20230484241)+2 种基金the support from the China Postdoctoral Science Foundation(2024M754084)the Postdoctoral Fellowship Program of CPSF(GZB20230931)the support from Initial Energy Science&Technology Co.,Ltd(IEST)。
文摘The dissolution of iron from the cathode and electrode/electrolyte interface(EEI)during long cycles significantly accelerates the aging process of LiFePO_(4)(LFP)/graphite batteries;there is a lack of systematic understanding of the spatial distribution of the EEI interface layer and the dissolve of Fe ions,especially in terms of the mechanism of the cathode-electrolyte interphase(CEI),solid electrolyte interphase(SEI),and iron dissolution.In this study,aged cells were subjected to continuous activation with constant current and multi-step segmented indirect activation(IA)and analyzed for capacity fade,impedance growth,and active Li^(+)mass loss at the EEI and nanoscale levels.The interaction between dissolved Fe^(2+)and the EEI in LFP/graphite pouch batteries was proposed and verified.The findings indicate that during IA process,the electric field facilitates the migration of solvated ions toward the electrodes,while simultaneously inhibiting the formation of organic species such as ROCO_(2)Li.The SEI primarily consists of a mixture of organic and inorganic small molecules,forming a continuous and uniform film on the electrode surface.This study demonstrates that IA favors the formation of a uniform EEI and offers constructive insights for advancing accelerated lifetime prediction strategies in lithium-ion batteries.
基金supported by the National Natural Science Foundation(42472325)the Fundamental Research Funds of Chinese Academy of Geological Science(SK202103).
文摘To elucidate the geographical differentiation characteristics and driving mechanisms of Dissolved Organic Matter(DOM)in typical rivers,this study conducted a multi-spectral investigation on three representative river types within Shandong Province:The mountainous Dawen River,the plain Tuhai River,and the artificial East Grand Canal.The DOM composition was analyzed using Ultraviolet-Visible(UV-Vis)absorption spectroscopy,Excitation-Emission Matrix(EEM)fluorescence spectroscopy,and parallel factor analysis(PARAFAC),while Principal Component Analysis(PCA)was employed to quantify the synergistic effects of natural processes and anthropogenic activities.Results revealed significant spatial heterogeneity in DOM composition and sources.The plain river exhibited the highest aromaticity(humic-like components:43.3%)due to long-term agricultural non-point source inputs and urban wastewater discharge.The mountain stream,shaped by complex terrain and relatively intact ecosystems,was dominated by autochthonous DOM derived from microbial metabolism,with higher Fluorescence Index(FI=2.12)and biological index(BIX=1.35)than other river types.The artificial canal retained protein-like components(64.2%),largely attributed to winter hydrological stagnation and disturbances from shipping activities.Further analysis demonstrated that geographical settings(e.g.,mountain terrain)and anthropogenic activities(e.g.,agriculture,shipping)jointly regulated DOM composition by altering the balance between input and transformation processes.Integrated fluorescence parameters and PCA results suggested differentiated management strategies:protecting ecological integrity in mountain streams to sustain selfpurification,enhancing non-point source interception in plain rivers,and mitigating shipping pollution in canals.This study systematically reveals the natural-anthropogenic coupling mechanisms driving DOM dynamics in northern China rivers,providing critical insights for precision water environment management at the watershed scale.
基金supported by the Integrated Management of Water Resources and Water Environment in the Yangtze River,Yellow River and Other Key Basins(No.2021YFC3201304)Beijing Water Group Research Institute(China)for its support.
文摘The essential step to improve the coagulation efficiency is to select and optimize the pre-oxidation process.Ultraviolet/sodium percarbonate(UV/SPC)can be employed as an alternative system to UV/H_(2)O_(2) in drinking water treatment plant operation,benefiting from the solid stability properties with the equivalent effect.At present,the studies on UV/SPC,and other UV/advanced oxidation processes(UV/H_(2)O_(2),UV/persulfate,UV/chlorine,etc.),mostly focus on the advanced water treatment after filtration.This study notes that UV/SPC has advantages in the pre-oxidized organics.UV/SPC improving the effect of coagulation on dissolved organic carbon(DOC)elimination by up to 25%,the optimal UV dose and SPC dosage are 600 mJ/cm^(2) and 20 mg/L verified by a pilot experiment;the decomposition degree and conversion of organics which is most conducive to follow-up coagulation treatment is obtained through the detailed comparison of the influence range of UV dose or the CSPC on the molecule structure of organics;the disparate role of UV was unraveled in UV photolysis pre-oxidation and UV/SPC pre-oxidation and coagulation,including the influence regularity of UV transmittance(UVT)and processing flow rate on UV dose;confirm that UV/SPC alleviates the risk of the generation of disinfection byproducts(DBPs)to 51.15%.This study corroborates the potential of UV/SPC as a pre-oxidation technology at the application level.
基金supported by the National Natural Science Foundation of China(Nos.42307524,and 51879103).
文摘China’s lakes are plagued by cadmium(Cd)pollution.Dissolved organic matter(DOM)significantly regulates Cd(II)transport properties at the sediment-water interface.Understanding the effects of different DOM components on the transportation properties of Cd(II)at the sediment-water interface is essential.In this study,typical DOM from different sources was selected to study Cd(II)mobility at the sediment-water interface.Results showed that terrestrial-derived DOM(fulvic acids,FA)and autochthonous-derived DOM(α-amylase,B1)inhibit Cd(II)sequestration by sediments(42.5%and 5.8%,respectively),while anthropogenic-derived DOM(sodium dodecyl benzene sulfonate,SDBS)increased the Cd(II)adsorption capacity by sediments by 2.8%.Fluorescence quenching coupling with parallel factor analysis(EEM-PARAFAC)was used to characterize different DOM components.The results showed that FA contains three kinds of components(C1,C3:protein-like components,C2:humic-like components);SDBS contains two kinds of components(C1,C2:protein-like components);B1 contains three kinds of components(C1,C2:protein-like components,C3:humic-like components).Three complex reaction modelswere used to characterize the ability of Cd(II)complex with DOM,and it was found that the humic-like component could hardly be complex with Cd(II).Accordingly,humic-like components compete for Cd(II)adsorption sites on the sediment surface and inhibit Cd(II)adsorption fromsediments.Fourier transform infrared spectroscopy(FTIR)of the sediment surface before and after Cd(II)addition was analyzed and proved the competitive adsorption theory.This study provides a better understanding of the Cd(II)mobilization behavior at the sediment-water interface and indicates that the input of humic-like DOM will increase the bioavailability of Cd.
基金supported by the National Key Research and Development Program of China(No.2019YFC1804202)the National Natural Science Foundation of China(Nos.22020102004 and 22125603)+1 种基金Tianjin Municipal Science and Technology Bureau(No.21JCZDJC00280)the Fundamental Research Funds for the Central Universities,and the Ministry of Education of China(No.T2017002).
文摘Polybrominated biphenyl ethers(PBDEs)and polycyclic aromatic hydrocarbons(PAHs)are commonly detected contaminants at e-waste recycling sites.Against the conventional wisdom that PBDEs and PAHs are highly immobile and persist primarily in shallowsurface soils,increasing evidence shows that these compounds can leach into the groundwater.Herein,we compare the leachabilities of PBDEs vs.PAHs from contaminated soils collected at an e-waste recycling site in Tianjin,China.Considerable amounts of BDE-209(0.3–2 ng/L)and phenanthrene(42–106 ng/L),the most abundant PBDE and PAH at the site,are detected in the effluents of columns packed with contaminated soils,with the specific concentrations varying with hydrodynamic and solution chemistry conditions.Interestingly,the leaching potential of BDE-209 appears to be closely related to the release of colloidal mineral particles,whereas the leachability of phenanthrene correlates well with the concentration of dissolved organic carbon in the effluent,but showing essentially no correlation with the concentration of mineral particles.The surprisingly different trends of the leachability observed between BDE-209 and phenanthrene is counterintuitive,as PBDEs and PAHs often co-exist at e-waste recycling sites(particularly at the sites wherein incineration is being practiced)and share many similarities in terms of physicochemical properties.One possible explanation is that due to its extremely low solubility,BDE-209 predominantly exists in free-phase(i.e.,as solid(nano)particles),whereas the more soluble phenanthrene is mainly sorbed to soil organic matter.Findings in this study underscore the need to better understand the mobility of highly hydrophobic organic contaminants at contaminated sites for improved risk management.
基金supported by the National Natural Science Foundation of China(No.42107052)Beijing Natural Science Foundation(No.JQ21031).
文摘As a widely used fertilizer,urea significantly promotes the leaching of dissolved organic nitrogen(DON)in soils and aggravates nitrogen contamination in groundwater.Clayminerals are considered the most important factor in retaining DON.However,the effect of urea on the retention of DON with different molecular weights by clay minerals is unknown.In this study,the retention of both low-molecular weight DON(LMWD)and high-molecular weight DON(HMWD)by clay minerals in the presence of urea was investigated.For this purpose,batch adsorption and soil column leaching experiments,characterization analysis(Fourier transform infrared spectroscopy X-ray diffraction,and X-ray photoelectron spectroscopy),and molecular dynamics simulations were carried out.Urea had a positive effect on the adsorption of LMWD,whereas a competitive effect existed for the adsorption of HMWD.The dominant interactions among DON,urea,and clay minerals included H-bonding,ligand exchange,and cation exchange.The urea was preferentially adsorbed on clay minerals and formed a complex,which provided more adsorption sites to LMWD and only a few to HMWD.The presence of urea increased the retention of LMWD and decreased the retention of HMWD in clay minerals.The retention capacity of LMWD increased by 6.9%–12.8%,while that of HMWD decreased by 6.7%–53.1%.These findings suggest that LMWD tended to be trapped in soils,while HMWD was prone to be leached into groundwater,which can be used to evaluate the leaching of DON from soil to groundwater.
基金supported by the National Natural Science Foundation of China(Nos.82173747,82373803)the Special Fund Project for Science and Technology Innovation Strategy of Guangdong Province(No.2021TQ060944)。
文摘Cancer vaccines are a notable area of immunotherapy due to their capacity to elicit specific antitumor immune responses and to create immune memory.However,they encounter challenges in clinical practice due to several bottlenecks,including tumor heterogeneity,low immunogenicity,immunosuppressive tumor environment,and delivery obstacles,which collectively impact their clinical effectiveness.In this study,we developed nanocomposites containing positively charged melittin(MEL)and negatively charged photosensitizer indocyanine green(ICG),embedded in dissolving microneedles(MEL/ICG-HA@DMNs).This approach allows precise drug delivery by creating microchannels that bypass the stratum corneum barrier,targeting superficial lesions directly.Our results demonstrated that the complexation of MEL and ICG significantly reduced the hemolytic activity of MEL while maintaining its ability to disrupt cell membranes.After loading MEL/ICG-HA into the microneedle,MEL/ICG-HA@DMNs not only effectively concentrated the drug at the tumor site,inducing localized hyperthermia and successfully ablating the tumor,but also formed an in situ whole-cell vaccine containing a rich source of tumor-associated antigens.Moreover,the system promoted dendritic cell maturation and increased the M1/M2 macrophage ratio,enhancing the immune response.By overcoming the limitations of traditional cancer vaccines,this system ensures precise drug delivery and robust immune activation.This innovative approach holds the potential to revolutionize cancer treatment,offering a new paradigm in precision oncology.
基金supported by the National Key Research and Development Program of China(No.2022YFC3204000).
文摘Lake Baiyangdian is one of China’s largest macrophyte-derived lakes,facing severe challenges related to water quality maintenance and eutrophication prevention.Dissolved organic matter(DOM)was a huge carbon pool and its abundance,property,and transformation played important roles in the biogeochemical cycle and energy flow in lake ecosystems.In this study,Lake Baiyangdian was divided into four distinct areas:Unartificial Area(UA),Village Area(VA),Tourism Area(TA),and Breeding Area(BA).We examined the diversity of DOM properties and sources across these functional areas.Our findings reveal that DOM in this lake is predominantly composed of protein-like substances,as determined by excitation-emission matrix and parallel factor analysis(EEM-PARAFAC).Notably,the exogenous tyrosine-like component C1 showed a stronger presence in VA and BA compared to UA and TA.Ultrahigh-resolution mass spectrometry(FT-ICR MS)unveiled a similar DOM molecular composition pattern across different functional areas due to the high relative abundances of lignan compounds,suggesting that macrophytes significantly influence the material structure of DOM.DOM properties exhibited specific associations with water quality indicators in various functional areas,as indicated by the Mantel test.The connections between DOM properties and NO_(3)-N andNH3-Nwere more pronounced in VA and BA than in UA and TA.Our results underscore the viability of using DOM as an indicator for more precise and scientific water quality management.
基金supported by the Director Fund Project provided by the Institute of Plant Nutrition,Resources and Environment,Beijing Academy of Agriculture and Forestry Sciences(No.YZS202101)the Youth Fund Project provided by Beijing Academy of Agriculture and Forestry Sciences(No.QNJJ202125)China Agriculture Research System of MOF and MARA.
文摘The dissolved organic matter(DOM)with high mobility and reactivity plays a crucial role in soil.In this study,the characteristics and phytotoxicity ofDOMreleased fromthe hydrochars prepared from different feedstocks(cowmanure,corn stalk and Myriophyllum aquaticum)under three hydrothermal carbonization(HTC)temperatures(180,200 and 220°C)were evaluated.The results showed that the hydrochars had high dissolved organic carbon content(20.15 to 37.65 mg/g)and its content showed a gradual reduction as HTC temperature increased.Three fluorescent components including mixed substance of fulvic acid-like and humic acid-like substances(C1,30.92%-58.32%),UVA humic acid-like substance(C2,25.27%-29.94%)and protein-like substance(C3,11.74%-41.92%)were identified in hydrochar DOM by excitation emission matrix spectra coupled with parallel factor analysis.High HTC temperature increased the relative proportion of aromatic substances(C1+C2)and humification degree of hydrochar DOM from cow manure,while it presented adverse effects on the hydrochar DOM from corn stalk and Myriophyllum.aquaticum.The principal component analysis suggested that feedstock type and HTC temperature posed significant effects on the characteristics of hydrochar DOM.Additionally,seed germination test of all hydrochar DOM demonstrated that the root length was reduced by 8.88%-26.43%in contrast with control,and the germination index values were 73.57%-91.12%.These findings provided new insights into the potential environmental effects for hydrochar application in soil.
基金The National Natural Science Foundation of China under contract Nos 42276255,41976228,42176227 and 42306262the National Polar Special Program under contract Nos IRASCC 01-01-02,IRASCC 02-02-03,and IRASCC 02-02-05the Scientific Research Fund of the Second Institute of Oceanography under contract Nos JG2211 and JG2212.
文摘Dissolved organic carbon(DOC)constitutes the largest organic carbon reservoir in the ocean and plays a vital role in the oceanic carbon cycle.However,research on DOC in Antarctica has been limited,largely due to difficulties in sample collection.In this study,we investigate chromophoric dissolved organic matter(CDOM)in the Cosmonaut Sea and Cooperation Sea,Antarctica.The relative abundances of CDOM,as indicated by the absorption coefficient at 254 nm(a_(254)),exhibit significant variability,ranging from 1.29 m^(-1) to 8.37 m^(-1).The diatom species B is the primary contributor to CDOM in the region influenced by the Antarctic slope current.Using excitation-emission matrix fluorescence spectroscopy coupled with parallel factor analysis(EEM-PARAFAC),we identify three fluorescent components:one protein-like component(C1)and two humic-like components(C2 and C3).Our findings indicate that strong microbial activity in the euphotic zones of the Cosmonaut Sea and Cooperation Sea serves as a primary pathway for the removal of protein-like substances while also acting as a significant source of humic-like substances.Microbial degradation likely accounts for the decoupling of the vertical distribution of DOC and phytoplankton.Furthermore,the intrusion of modified circumpolar deep water(mCDW)into the euphotic zones of open ocean areas influences the distribution of CDOM at depths shallower than 200 m.These results have important implications for enhancing our understanding of the dynamics of CDOM and DOC in east Antarctica,as well as for improving assessments of the carbon cycle.
基金supported by the National Natural Science Foundation of China(Nos.41830753,42277201,42377242,and 41977286)the Scientific Research Foundation of Guangzhou University(No.YJ2023027)the College Student Innovation and Entrepreneurship Training Program(No.S202311078057).
文摘Arsenic-contaminated groundwater is widely used in agriculture.To meet the increasing demand for safe water in agriculture,an efficient and cost-effective method for As removal from groundwater is urgently needed.We hypothesized that Fe(oxyhydr)oxide(FeOOH)minerals precipitated in situ from indigenous Fe in groundwater may immobilize As,providing a solution for safely using As-contaminated groundwater in irrigation.To confirm this hypothesis and identify the controlling mechanisms,we comprehensively evaluated the transport,speciation changes,and immobilization of As and Fe in agricultural canals irrigated using As-contaminated groundwater.The efficiently removed As and Fe in the canals accumulated in shallow sediment rather than subsurface sediment.Linear combination fitting(LCF)analysis of X-ray absorption near edge spectroscopy(XANES)indicated that As(Ⅴ)was the dominant As species,followed by As(Ⅲ),and therewas no FeAsO_(4) precipitate.Sequential extraction revealed higher contents of amorphous FeOOH and associated As in shallower sediment than in the subsurface layer.Stoichiometric molar ratio calculations,SEM-EDS,FTIR,and fluorescence spectroscopy collectively demonstrated that the microbial reductive dissolution of amorphous FeOOH proceeded via reactive dissolved organic matter(DOM)consumption in subsurface anoxic porewater environment facilitating high labile As,whereas in surface sediment,the in situ-generated amorphous FeOOH was stable and strongly inhibited As release via adsorption.In summary,groundwater Fe^(2+)can efficiently precipitate in benthic surface sediment as abundant amorphous FeOOH,which immobilizes most of the dissolved As,protecting agricultural soil from contamination.This field research supports the critical roles of the phase and reactivity of in situ-generated FeOOH in As immobilization and provides new insight into the sustainable use of contaminated water.
基金financially supported by the National Natural Science Foundation of China(Nos.52379048 and 52079112)the Key Research and Development Program of Shaanxi Province,China(No.2022ZDLNY03-03)the Major Science and Technology Engineering Innovation Project of Shandong Province,China(No.2020CXGC 010808)。
文摘Aerated drip irrigation(ADI)is an important practice for promoting soil fertility and crop productivity in greenhouse vegetable production,yet little research has comprehensively investigated its effects on the functional traits of carbon(C)-cycling microorganisms.In this study,we sought to assess the potential efficacy of ADI in increasing soil organic C(SOC)by changing soil microbial communities and the expressions of genes associated with C cycling.To this end,we adopted a metagenomic approach to compare the effects of ADI with three dissolved oxygen concentrations(10,15,and 20 mg L^(-1))during a three-season tomato cultivation experiment in northern China.The results revealed that the 10 mg L^(-1)treatment led to a significant increase in the abundance of korA/B genes(associated with the reductive tricarboxylic acid cycle)in the C fixation pathway,whereas the 15 mg L^(-1)treatment increased the abundances of cbbL/R and coxL/S genes associated with the Calvin cycle and carbon monoxide oxidation,respectively.In addition,based on a co-occurrence network analysis,we observed a positive correlation between cbbL and coxS.Interestingly,r-selected microorganisms,such as Proteobacteria and Actinobacteria,characterized by rapid cell multiplication and high biomass production,were identified as the primary contributors to C fixation and were the main predictors of SOC pools.In contrast,the 20 mg L^(-1)treatment was found to adversely influence C fixation,although the enhanced C degradation could be attributed to the extracellular enzymes secreted by K-selected microorganisms.Collectively,our findings indicate that ADI with dissolved oxygen concentrations 15 mg L^(-1)can promote SOC content by altering the life history strategies of r-selected microorganisms and genes associated with C fixation.These findings will provide valuable references for agroecosystem irrigation management,help improve soil fertility,and promote sustainable production.
基金supported by the National Natural Science Foundation of China(No.42307090)the Open Subject from State Environmental Protection Key Laboratory of Aquatic Ecosystem Health in theMiddle and Lower Reaches of Yangtze River(No.AEHKF2023008).
文摘The copper complexing of dissolved organic matter released from hydrochar(HDOM)affects the former’s environmental behavior.In this study,how hydrothermal temperatures(180,220 and 260℃)influence the molecular-level constitutions and Cu(II)binding features of HDOM were elucidated via fourier transform ion cyclotron resonance mass spectrometry and multi-spectroscopic analysis.The findings demonstrated that the almost HDOM molecules had the traits of lower polarity and higher hydrophobicity.As the hydrothermal temperature increased,the molecules with particularly high relative strength gradually disappeared,average molecular weight,percentages of CHON and aliphatic compounds of HDOM reduced while the percentages of CHO and aromatic compounds increased.In general,the fluorescence quenching of Cu(II)weakened as hydrothermal temperature rose and the Cu(II)binding stability constants of fluorophores in HDOM were 4.50–5.31.In addition,the Cu(II) binding order of fluorophores in HDOM showed temperature heterogeneities, andpolysaccharides or aromatic rings of non-fluorescent substances had the fastest responsesto Cu(II) binding. Generally, fluorescent components tend to bind Cu(II) at relatively traceconcentrations (0–40 μmol/L), whereas non-fluorescent substances tend to the bind Cu(II)at relatively higher concentrations (50–100 μmol/L). This study contributed to the predictionof the potential environmental behaviors and risks of Cu(II) at the molecular level afterhydrochar application.
基金supported by the National Natural Science Foundation of China(Nos.42207450,42067056,and 21866017)the Yunnan Fundamental Research Projects(No.202101BE070001-013)the Foundation for Distinguished Young Talents of Yunnan Province(No.202101AV070006).
文摘Dissolved black carbon(DBC)plays a crucial role in the migration and bioavailability of iron in water.However,the properties of DBC releasing under diverse pyrolysis conditions and dissolving processes have not been systematically studied.Here,the compositions of DBC released from biochar through redox processes dominated by bacteria and light were thoroughly studied.It was found that the DBC released from straw biochar possess more oxygen-containing functional groups and aromatic substances.The content of phenolic and carboxylic groups in DBC was increased under influence of microorganisms and light,respectively.The concentration of phenolic hydroxyl groups increased from 10.0~57.5 mmol/gC to 6.6~65.2 mmol/gC,and the concentration of carboxyl groups increased from49.7~97.5 mmol/gC to 62.1~113.3 mmol/gC.Then the impacts of DBC on pyrite dissolution andmicroalgae growth were also investigated.The complexing Fe^(3+)was proved to play a predominant role in the dissolution of ferrous mineral in DBC solution.Due to complexing between iron ion and DBC,the amount of dissolved Fe in aquatic water may rise as a result of elevated number of aromatic components with oxygen containing groups and low molecular weight generated under light conditions.Fe-DBC complexations in solution significantly promoted microalga growth,which might be attributed to the stimulating effect of dissolved Fe on the chlorophyll synthesis.The results of study will deepen our understanding of the behavior and ultimate destiny of DBC released into an iron-rich environment under redox conditions.
基金Project(2020YFC1908802)supported by the National Key Research and Development Project of China。
文摘Biochar-derived dissolved organic matter(BCDOM),an essential component of biochar,plays a vital role in regulating the physicochemical and biological properties of soils during biochar application.However,the influence of BCDOM on soil organisms has not been clearly explained.Hence,this review aims to discuss the factors affecting BCDOM and its interaction with soil substances including organic pollutants,heavy metals,and microorganisms.Results displayed that the quantity of BCDOM ranges from 0.17 to 37.03 mg/g,which was influenced by feedstock,preparation methods of biochar,and extraction methods.With the decrease in lignin content of feedstocks,carbonization temperature,and acidity of extraction solution,the content of BCDOM increased.Through complexation and adsorption,protein-like components in BCDOM interact with heavy metals,promoting the adsorption and immobilization of heavy metals onto biochar.Furthermore,BCDOM enhances the adsorption of organic pollutants by biochar throughπ−πinteractions,hydrogen bonding,and redox processes.More importantly,BCDOM promotes plant growth by enhancing microbial activities,providing nutrients,and improving soil properties.However,the transport and fate of BCDOM in soil have not been well studied,and more researches are needed to explore the interaction mechanisms between BCDOM and soil organisms.
基金supported by the Central Guiding Local Science and Technology Development Fund of Shandong-Yellow River Basin(No.YDZX2023019)Shandong Natural Science Foundation of China(Nos.ZR2020QF067 and ZR2023QD073)+6 种基金the Discipline Cluster Research Project of Qingdao University“Deep mining and intelligent prediction of multimodal big data for marine ecological disasters”(No.20240604)sourced from the International Argo Program and the national programs that contribute to it(https://argo.ucsd.edu)the CMEMS(http://marine.copernicus.eu/)the CDS(https://cds.climate.copernicus.eu/)the EMODnet(https://www.emodnet-chemistry.eu/)obtained from the ERA5(https://www.ecmwf.int)derived from the Glob Colour Project(http://globcolour.info).
文摘Oceanic dissolved oxygen(DO)concentration is crucial for assessing the status of marine ecosystems.Against the backdrop of global warming,DO shows a general decrease,posing a threat to the health of marine ecosystems.Therefore,there is an urgent need to develop advanced tools to characterize the spatio-temporal variations of three-dimensional(3D)DO.To address this challenge,this study introduces the Light Gradient Boosting Machine(Light-GBM),combining satellite remote sensing and reanalysis data with Biogeochemical Argo data to accurately reconstruct the 3D DO structure in the Mediterranean Sea from 2010 to 2022.Various environmental parameters are incorporated as inputs,including spatiotemporal features,meteorological characteristics,and ocean color properties.The LightGBM model demonstrates excellent performance on the testing dataset with R^(2) of 0.958.The modeled DO agrees better with in-situ measurements than products from numerical models.Using the Shapley Additive exPlanations method,the contributions of input features are assessed.Sea surface temperatures provide a correlation with DO at the sea surface,while spatial coordinates supplement the view of the ocean interior.Based on the reconstructed 3D DO structure,we identify an oxygen minimum zone in the western Mediterranean that expands continuously,reaching depths of approximately 300–800 m.The western Mediterranean exhibits a significant declining trend.This study enhances marine environmental evidence by proposing a precise and cost-effective approach for reconstructing 3D DO,thereby offering insights into the dynamics of DO variations under changing climatic conditions.
基金supported by the National Key Research and Development Program of China(No.2022YFB3803600)the National Natural Science Foundation of China(Nos.22202187,22361142704,22238009,U24A2071,and 52272290)+4 种基金the National Postdoctoral Program for Innovative Talents(No.BX2021275)the Natural Science Foundation of Hubei Province of China(No.2022CFA001)the Project funded by China Postdoctoral Science Foundation(No.2022M712957)the Postdoctoral Funding Program of Hubei Province.Chuanbiao Bie and Bicheng Zhu would like to thank the China Scholarship Council(CSC)for its financial supportsupport from Australian Research Council Discovery Early Career Award(No.DE220100429).
文摘The inefficiency of photocatalytic overall water splitting is well documented and has been extensively studied.However,a crucial aspect of this process,the side reaction,has often been overlooked.In this study,we investigate the impact of side reactions on photocatalytic overall water splitting by monitoring factors such as dissolved oxygen,reactive oxygen species,and hydrogen peroxide.Further insights into the side reaction are obtained through the introduction of a platinum cocatalyst.Our findings reveal that dissolved oxygen significantly contributes to the side reaction by promoting the production of hydrogen peroxide.This byproduct is generated at the expense of electrons needed for the hydrogen evolution reaction,thereby reducing the overall efficiency of photocatalytic water splitting.This article aims to provide guidance on future research directions in the field of water splitting,with a particular emphasis on photocatalysis.