Polynyas and their adjacent seasonal ice zones(SIZs)represent the most productive regions in the Southern Ocean,supporting unique food webs that are highly sensitive to climate change.Understanding the dynamics of phy...Polynyas and their adjacent seasonal ice zones(SIZs)represent the most productive regions in the Southern Ocean,supporting unique food webs that are highly sensitive to climate change.Understanding the dynamics of phytoplankton and the carbon pool in these areas is crucial for assessing the role of the Southern Ocean in global carbon cycling.During the late stage of an algal bloom,seawater samples at 14 stations were collected in the Amundsen Sea Polynya(ASP)and adjacent SIZ.Using nutrients,phytoplankton pigments,organic carbon(OC),remote sensing data,and physicochemical measurements,as well as CHEMTAX model simulations,we investigated the response of the phytoplankton crops,taxonomic composition,and OC pool to environmental factors.Our analyses revealed that hydrodynamic regimes of the polynya,adjacent SIZs and open sea were regulated by the regionally varying intrusion of Circumpolar Deep Water,photosynthetically active radiation and sea ice melt water.The ASP exhibited the highest seasonal nutrient utilization rates[ΔN=(1059±386)mmol/m^(2),ΔP=(50±17)mmol/m^(2) andΔSi=(956±904)mmol/m^(2)],while the open sea had lower rates.The integrated chlorophyll a(Chl a)concentration at depths of 0–200 m ranged from 20.4 mg/m^(2) to 1420.0 mg/m^(2) and peaked in the polynya.In the study area,Haptophytes Phaeocystis antarctica was the dominant functional group(34%±27%),and diatoms acted as a secondary contributor(23%±14%).The major functional group and particulate OC(POC)contributor varied from diatoms(36%±12%)in the open sea to haptophytes(48%±31%)in the polynya waters.Strong light conditions and microelement limitations promoted the dominance of P.antarctica(low Fe forms)dominance in the ASP.The strong correlations between the POC and Chl a depth-integrated concentration suggest that the POC was primarily derived from phytoplankton,while dissolved OC(DOC)was influenced by consumer activity and water mass transport.In addition,the transport of OC in the upper 200 m of the water column within the ASP was quantified,revealing the predominantly westward fluxes for both DOC[9.0 mg/(m^(2)·s)]and POC[7.2 mg/(m^(2)·s)].The latitudinal transport exhibited the northward transport of DOC[8.1 mg/(m^(2)·s)]and southward transport of POC[4.3 mg/(m^(2)·s)]movement.These findings have significant implications for enhancing our understanding of how hydrodynamics influence OC cycling in polynya regions.展开更多
The melting of seasonal sea ice in Antarctica plays a pivotal role in the region’s carbon cycle,influencing global carbon storage and the exchange of carbon between the atmosphere and the ocean.However,the impact of ...The melting of seasonal sea ice in Antarctica plays a pivotal role in the region’s carbon cycle,influencing global carbon storage and the exchange of carbon between the atmosphere and the ocean.However,the impact of variability in the timing of seasonal sea ice retreat on the flux and composition of sinking particulate matter remains to be elucidated.In this study,we deployed sediment traps in Prydz Bay during the austral summers of 2019/2020 and 2020/2021,noting that sea ice melting occurred approximately one and a half months earlier in the former summer compared to the latter.We analyzed sediment trap data,which included total mass flux(TMF),particulate organic carbon(POC),biogenic silica(BSi),particulate inorganic carbon,and lithogenic particle(Litho)fluxes,as well as the stable isotopesδ^(13)C andδ^(15)N of particulate organic matter(POM).Additionally,we incorporated remote sensing data on sea ice concentration and chlorophyll a.This dramatic delay in sea ice melting timing could result in a significant increase in TMF,BSi and POC fluxes in the summer of 2020/2021 compared to 2019/2020.Elevated BSi fluxes and more ^(13)C-depleted POC in the austral summer of 2020/2021 suggest that the delayed melting of sea ice may have stimulated the productivity of centric diatoms.Furthermore,the higher BSi/POC ratio and more negativeδ^(15)N values of POM,along with a reduced presence of krill in the traps,indicate a diminished grazing pressure from zooplankton,which collectively enhanced the sedimentation efficiency of POC during the austral summer of 2020/2021.These findings highlight the critical role of sea ice melting timing in regulating productivity,flux and composition of sinking particulate matter in the Prydz Bay ecosystem,with significant implications for carbon cycling in polar oceans.展开更多
Catalytic oxidation of biomass-derived 5-hydroxymethylfurfural(HMF)to 2,5-furandicarboxylic acid(FDCA,an alternative bioplastic monomer to petroleum-derived terephthalic acid),has been identified as an important bioma...Catalytic oxidation of biomass-derived 5-hydroxymethylfurfural(HMF)to 2,5-furandicarboxylic acid(FDCA,an alternative bioplastic monomer to petroleum-derived terephthalic acid),has been identified as an important biomass conversion reaction in bio-based polyester industry.However,it is still challenging to acquire a high FDCA yield from the selective oxidation of HMF at low temperatures.Herein,a ternary metal-based catalyst was prepared by loading AuPdPt noble metal nanoparticles on the oxygen-rich vacancy titanium dioxide layer deposited on natural clay mineral halloysite nanotubes(HNTs),and the catalytic activity was examined for air-oxidation of HMF to FDCA in water at ambient temperature(30℃).By adjusting the Au/Pd/Pt ratio,a 93.6%FDCA yield was achieved with the optimal Au_(0.5)Pd_(0.2)Pt_(0.3)/TiO_(2)@HNTs catalyst,which revealed an impressive FDCA formation rate of 67.58 mmol g^(-1)h^(-1)and an excellent TOF value of 17.54 h^(-1)under normal air pressure at 30℃,surpassing the performance of mono-and bimetallic-based catalysts.Theoretical calculation and catalytic performance study clarified the structure-activity relationship.It was found that the ternary metal and oxygen vacancies revealing synergistic enhancement of ambient temperature catalyzed HMF air-oxidation via electronic structure tuning and adsorption intensification.DFT and kinetics study demonstrated that the presence of ternary metal significantly improved the adsorption capacity of substrate and enhanced the rate-determining step of the key intermediate 5-hydroxymethyl-2-furanocarboxylic acid(HMFCA)oxidation when compared to mono-and bimetal.Additionally,the TiO_(2)@HNTs support with high oxygen vacancy concentration facilitated the adsorption of oxygen,synergistically working with the ternary metal to activate and low the energy barriers for the generation of superoxide radical,thus enhancing the FDCA formation.This work offers a novel strategy for designing ternary metal-based catalysts for low-energy catalytic oxidation reactions.展开更多
Nutrient uptake status dominates phytoplankton biomass and community structure in the Southern Ocean during austral summer,yet how nutrient utilization variability responds to phytoplankton community succession is sti...Nutrient uptake status dominates phytoplankton biomass and community structure in the Southern Ocean during austral summer,yet how nutrient utilization variability responds to phytoplankton community succession is still unclear,partly due to lack of data spanning the entire summer.In this study,nitrate,phosphate,and silicate combined with temperature,salinity,and apparent oxygen utilization(AOU)were analyzed along 45°E in the Cosmonaut Sea during December 2019,January 2021,and February 2022.The variations in nutrient utilization in the euphotic layer were studied using biogeochemical tracers,and seasonal nutrient depletion was also estimated.The results showed that nutrient distribution varied significantly from December to February.Significant positive correlations were observed for nitrate and silicate concentrations with salinity and AOU,indicating that nutrient distributions were mainly influenced by water mass and phytoplankton production.Increasing∆[N*]and decreasing∆[Si*]in the upper 50 m were observed south of 63.5°S from December to February,which possibly contributed to a progressive shift in dominant phytoplankton population from Phaeocystis antarctica to diatoms.The seasonal nutrient depletion generally increased from December to February.Moreover,the consumption of silicate substantially increased compared to nitrate,indicating that the abundance of diatoms was increasing with time during the austral summer.Our observations suggest that nutrient utilization status is closely related to phytoplankton community structure in the euphotic layer of the Cosmonaut Sea.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
Expanding the specific surface area of substrates and carrying out precise surface engineering of imprinted nanocavities are crucial methods for enhancing the identification efficiency of molecularly imprinted polymer...Expanding the specific surface area of substrates and carrying out precise surface engineering of imprinted nanocavities are crucial methods for enhancing the identification efficiency of molecularly imprinted polymers(MIPs).To implement this synergistic strategy,bioinspired surface engineering was used to incorporate dual covalent receptors via precise post-imprinting modifications(PIMs)onto mesoporous silica nanosheets.The prepared sorbents(denoted as‘‘D-PMIPs”)were utilized to improve the specific identification of adenosine 5-monophosphate(AMP).Significantly,the mesoporous silica nanosheets possess a high surface area of approximately 498.73 m^(2)·g^(-1),which facilitates the formation of abundant specific recognition sites in the D-PMIPs.The dual covalent receptors are valuable for estab-lishing the spatial orientation and arrangement of AMP through multiple cooperative interactions.PIMs enable precise site-specific functionalization within the imprinted cavities,leading to the tailor-made formation of complementary binding sites.The maximum number of high-affinity binding sites(Nmax)of the D-PMIPs is 39.99 lmol·g^(-1),which is significantly higher than that of imprinted sorbents with a sin-gle receptor(i.e.,S-BMIPs or S-PMIPs).The kinetic data of the D-PMIPs can be effectively described by a pseudo-second-order model,indicating that the main binding mechanism involves synergistic chemisorption from boronate affinity and the pyrimidine base.This study suggests that using dual cova-lent receptors and PIMs is a reliable approach for creating imprinted sorbents with high selectivity,allow-ing for the controlled engineering of imprinted sites.展开更多
High applied thermal-stability and superior structural property for activated carbon adsorbent are extremely promising,which also is the determining short slab in volatile organic compounds(VOCs)adsorption application...High applied thermal-stability and superior structural property for activated carbon adsorbent are extremely promising,which also is the determining short slab in volatile organic compounds(VOCs)adsorption applications.Herein,we develop the outstanding engineering carbon adsorbents from waste shaddock peel which affords greatly-enhanced thermal-stability and super structural property(S_(Lang)=4962.6 m2·g^(-1),Vmicro=1.67 cm^(3)·g^(-1)).Such character endows the obtained adsorbent with ultrahigh adsorption capture performance of VOCs specific to benzene(16.58 mmol·g^(-1))and toluene(15.50 mmol·g^(-1),far beyond traditional zeolite and activated carbon even MOFs materials.The structural expression characters were accurately correlated with excellent adsorption efficiency of VOCs by studying synthetic factor-controlling comparative samples.Ulteriorly,adsorption selectivity prediction at different relative humidity was demonstrated through DIH(difference of the isosteric heats),exceedingly highlighting great superiority(nearly sixfold)in selective adsorption of toluene compared to volatile benzene.Our findings provide the possibility for practical industrial application and fabrication of waste biomass-derived outstanding biochar adsorbent in the environmental treatment of threatening VOCs pollutants.展开更多
The ecosystem of the sea region adjacent to the Antarctic Peninsula is undergoing remarkable physical and biological changes, in the context of global warming. However, understanding of the dynamics of phytoplankton t...The ecosystem of the sea region adjacent to the Antarctic Peninsula is undergoing remarkable physical and biological changes, in the context of global warming. However, understanding of the dynamics of phytoplankton taxonomic composition in this marginal ice zone remains unclear. In this study, seawater samples collected from 36 stations in the northeastern Antarctic Peninsula were analyzed for nutrients and phytoplankton pigments.Combining with CHEMTAX analysis, remote sensing data, and physicochemical measurements, we investigated the relationships between phytoplankton crops, taxonomic composition, and marine environmental drivers.Integrated chlorophyll a(Chl a) concentrations(200 m) varied from 8.9 mg/m^(2)to 64.2 mg/m^(2), with an average of(23.2±12.0) mg/m^(2)and higher phytoplankton biomass concentrated in the coastal region of South Orkney Island and South Shetland Island. Diatoms were the dominant functional group(63%±21%). Higher proportions of diatoms were associated with higher Chl a(r=0.40, p<0.01), stable water columns(r=0.20, p<0.01), higher Si/P ratios(r=0.34, p<0.01), higher photosynthetically active radiation intensity(r=0.64, p<0.01), and higher sea ice melt water contributions(MWC, r=0.20, p<0.01). Conversely, Phaeocystis antarctica contributed a smaller overall proportion(31%±18%) and was more concentrated in the offshore water masses(e.g., Philip Ridge and South Scotia Ridge) with lower light levels(r=-0.58, p<0.01), deeper mixed layer depths(r=0.17, p<0.05), higher nutrient concentrations(e.g., N, P, and Si, r>0.35, p<0.01), and lower MWC(r=-0.20, p<0.01). In comparison, the total contribution from green flagellates(4%±5%), cryptophyta(1%±3%), dinoflagellates(1%±4%), and cyanobacteria(1% ± 5%) was only 6%. In offshore regions with well-mixed water, less varied taxonomic composition and lower crops with a higher proportion of nanophytoplankton were observed. In contrast, significantly decreasing crops below the mixed layer depth was observed in water columns with strong stratification, where the dominant phytoplankter changed from diatoms to P. antarctica. These findings have important implications for better understanding the future dynamics of marine ecosystems in the sea area adjacent to the Antarctic Peninsula.展开更多
Sediment collapse and subsequent lateral downslope migration play important roles in shaping the habitats and regulating sedimentary organic carbon(SOC)cycling in hadal trenches.In this study,three sediment cores were...Sediment collapse and subsequent lateral downslope migration play important roles in shaping the habitats and regulating sedimentary organic carbon(SOC)cycling in hadal trenches.In this study,three sediment cores were collected using a human-occupied vehicle across the axis of the southern Yap Trench(SYT).The total organic carbon(TOC)and total nitrogen(TN)contents,δ13C,radiocarbon ages,specific surface areas,and grain size compositions of sediments from three cores were measured.We explored the influence of the lateral downslope transport on the dispersal of the sediments and established a tentative box model for the SOC balance.In the SYT,the surface TOC content decreased with water depth and was decoupled by the funneling effect of the V-shaped hadal trench.However,the sedimentation(0.0025 cm/a)and SOC accumulation rates(∼0.038 g/(m^(2)·a)(in terms of OC))were approximately 50%higher in the deeper hadal region than in the abyssal region(0.0016 cm/a and∼0.026 g/(m^(2)·a)(in terms of OC),respectively),indicating the occurrence of lateral downslope transport.The fluctuating variations in the prokaryotic abundances and the SOC accumulation rate suggest the periodic input of surficial sediments from the shallow region.The similar average TOC(0.31%–0.38%),TN(0.06%–0.07%)contents,and SOC compositions(terrestrial OC(11%–18%),marine phytoplanktonic OC(45%–53%),and microbial OC(32%–44%))of the three sites indicate that the lateral downslope transport has a significant mixing effect on the SOC composition.The output fluxes of the laterally transported SOC(0.44–0.56 g/(m^(2)·a)(in terms of OC))contributed approximately(47%–73%)of the total SOC input,and this proportion increased with water depth.The results of this study demonstrate the importance of lateral downslope transport in the spatial distribution and development of biomes.展开更多
Molecularly imprinted polymers (MIPs) have great potential as adsorbents for selective adsorption and separation of nucleoside compounds,but effectively enhancing the affinity of recognition sites by adjusting the for...Molecularly imprinted polymers (MIPs) have great potential as adsorbents for selective adsorption and separation of nucleoside compounds,but effectively enhancing the affinity of recognition sites by adjusting the forces between template molecules and functional monomers remains an important challenge.In this work,a surface imprinting strategy was used to construct bowl-shaped molecularly imprinted composite sorbents (BHPN@MIPs) based on polydopamine (PDA) particles and have achieved selective separation and purification of 2'-deoxyadenosine (dA).Where by the base complementary pairing interaction of the combined template molecule d A and the pyrimidine functional monomer can enhance the preassembly force,and the hydrophilic bowl-shaped PDA can provide a larger storage space contact efficiency of d A in the test solution,causing the site utilization much higher and improving the kinetic adsorption performance.The equilibrium adsorption time and maximum adsorption capacity of60 min and 328.45μmol·g^(-1)were observed by static adsorption experiments,and the selectivity experimental results showed an imprinting factor IF of 1.30.After four adsorption–desorption cycles,the initial adsorption equilibrium adsorption capacity of BHPN@MIPs still retained 91.14%.By evaluating the selective adsorption of d A in spiked human serum solutions,BHPN@MIPs can be used to selectively enrich and analyze target d A in complex biological samples.展开更多
TiO2 nanoparticles（NPs） could adversely impact aquatic ecosystems. However, the aggregation of these NPs could attenuate this effect. In this work, the biological effects of TiO2 NPs on a marine microalgae Isochrysi...TiO2 nanoparticles（NPs） could adversely impact aquatic ecosystems. However, the aggregation of these NPs could attenuate this effect. In this work, the biological effects of TiO2 NPs on a marine microalgae Isochrysis galbana were investigated. The aggregation kinetics of TiO2 NPs under different conditions was also investigated to determine and understand these effects. Results showed that, though TiO2 NPs had no obvious impact on the size and reproducibility of algal cells under testing conditions, they caused a negative effect on algal chlorophyll, which led to a reduction in photosynthesis. Furthermore, fast aggregation of TiO2 NPs occurred under all conditions, especially at the pH close to the p Hzpc. Increasing ionic strength and NP concentration also enhanced the aggregation rate.The aggregation and the following sedimentation of TiO2 NPs reduced their adverse effects on I. galbana.展开更多
The ecosystems in Southern Ocean(SO)are undergoing significant changes in the context of climate change.To identify environment-phytoplankton feedbacks in SO,seawater samples were collected in the Cosmonaut Sea(CS)dur...The ecosystems in Southern Ocean(SO)are undergoing significant changes in the context of climate change.To identify environment-phytoplankton feedbacks in SO,seawater samples were collected in the Cosmonaut Sea(CS)during the 37 th China Antarctic Research Expedition(Jan.2021)(CHINARE-37)and subjected to analysis of particulate organic carbon(POC)and phytoplankton pigments.The remote sensing data,CHEMTAX community compositional modeling analysis,and physicochemical measurements were combined to explore the spatial variation of phytoplankton crops,taxonomic composition,and their environmental drivers.Historical phytoplankton community data from the area were also compared against those of this study to investigate inter-annual community differences and their potential causes.The column-integrated POC and chlorophyll-a(Chl-a)concentrations were 12.0±4.9 g/m^(2) and 73.8±50.5 mg/m^(2),respectively.The two most dominant taxa were haptophyte that are adapted to high Fe availability(Hapt-HiFe,mainly Phaeocystis antarctica)and Diatoms-A(Phaeodactylum tricornutum)that contributed to 33%±25%and 24%±14%to the total phytoplankton crops,respectively.Through cluster analysis,the study area was divided into two regions dominated by Hapt-HiFe and Diatoms-A,respectively.Spatially,Hapt-HiFe was mainly concentrated in the southwest coastal area that featured low temperatures,low salinity,and shallow euphotic zones.The coastal region southwest of the southern boundary of the Antarctic circumpolar current was experiencing a bloom of Hapt-HiFe during the study period that significantly contributed to the POC pool and Chl-a concentrations(R=0.46,P<0.01;R=0.42,P<0.01).Besides,the dominance of Hapt-HiFe in the CS suggests a high biological availability of dissolved Fe that is primarily associated with inputs from sea ice melt and upwellings.展开更多
The Southern Ocean breeds a special ecosystem.The evolution and adaptability of Antarctic marine organisms is a key research field of the Scientific Committee on Antarctic Research.The study of the Antarctic marine ec...The Southern Ocean breeds a special ecosystem.The evolution and adaptability of Antarctic marine organisms is a key research field of the Scientific Committee on Antarctic Research.The study of the Antarctic marine ecosystem is also one of the tasks of Chinese National Antarctic Research Expedition(CHINARE).However,the early investigations by Chinese scientists mainly focused on plankton and benthos,as well as their environmental variables.Since 2019,financially supported by National Polar Special Program“Impact and Response of Antarctic Seas to Climate Change”(IRASCC),the research objects have been gradually expanded to large marine animal,such as birds and mammals,and other related disciplines.展开更多
The rapid expansion of the chemical and pharmaceutical industries has resulted in the introduction of various sources of micropollutants into the environment,posing threats to drinking water quality and public health....The rapid expansion of the chemical and pharmaceutical industries has resulted in the introduction of various sources of micropollutants into the environment,posing threats to drinking water quality and public health.Membrane separation technology offers a promising solution with low energy use,high-quality effluent,and operational simplicity.Here,we developed fluffy layered double hydroxides(LDH)/graphene oxide(GO)2D membranes,specifically tannic acid-mediated LDH-GO/GO-TA composite membranes(LG/GT).The integration of GO nanosheets regulated the growth of LDH,enhancing electron transfer and adsorption-driven catalytic performance.This design enabled LDH-GO to activate peroxymonosulfate(PMS)and completely degraded Rhodamine B(RhB)within 10 min.The Gaussian calculation was combined with this finding,which could explain the catalytic self-cleaning in the separation process.The TA-mediated enhancement further increased the RhB rejection of LG/GT-7.5 to 99.23%.Additionally,the needle/sheet structure significantly improved permeance to 358.28 L m^(-2) h^(-1) bar^(-1),surpassing the L/GT-7.5 performance(e.g.338.53 L m^(-2) h^(-1) bar^(-1)),indicating superior pore formation and water mass transfer.The heterostructure between GO and LDH greatly improved cycling stability,with the membrane maintaining a permeance of 282.71 L m^(-2) h^(-1) bar^(-1) and a rejection of 97.97% despite 20 cycles.This work demonstrated the potential of fluffy layered LDH 2D membranes for enhanced wastewater treatment applications.These findings suggested significant potential for practical implementation in industrial wastewater treatment processes,offering a sustainable and efficient solution to water pollution challenges.展开更多
MXenes,an extensive family of two-dimensional(2D)materials,have attracted significant attention across diverse fields owing to their exceptional biological,optoelectronic,mechanical,and chemical properties,enabling th...MXenes,an extensive family of two-dimensional(2D)materials,have attracted significant attention across diverse fields owing to their exceptional biological,optoelectronic,mechanical,and chemical properties,enabling their application in numerous fields.Among these,photothermal water evaporation(PWE)has emerged as a particularly promising approach in wastewater treatment,driven by the escalating demand for fresh and pure water.Despite the development of various evaporators to address water scarcity,challenges such as low evaporation efficiency and limited scalability hinder their practical implementation.Over the past decade,MXenes have gained substantial interest owing to their unique elemental composition,porous structure,and surface terminations,which result in remarkable physical and chemical properties that depend on their synthesis methods.However,a key challenge in leveraging MXenes lies in their inherent instability,as they are prone to rapid oxidation upon exposure to air.Stabilizing pristine MXenes is,therefore,critical for their long-term application in PWE.This review highlights strategies to enhance the oxidation stability of MXenes through the incorporation of protective materials such as polymers,delignified wood(DW),and carbonaceous compounds,thereby improving their performance in PWE systems.Furthermore,this review delves into the development of MXene-based composite materials,exploring factors and mechanisms pertinent to their role in PWE.This comprehensive analysis provides valuable insights for researchers and practitioners in the field of wastewater treatment.展开更多
The highly reactive iron(FeHR)in marine sediments is a key driver of the iron-carbon coupled biogeochemical cycle.However,rare is known on its speciation and environmental regulation mechanisms in the climate-sensitiv...The highly reactive iron(FeHR)in marine sediments is a key driver of the iron-carbon coupled biogeochemical cycle.However,rare is known on its speciation and environmental regulation mechanisms in the climate-sensitive West Antarctic region.This study investigated the spatial distribution of FeHRcontent and composition in surface sediments of the Ross Sea,examined the synergistic regulatory mechanisms of chemical weathering intensity(quantified by the chemical index of alteration,CIA),bedrock properties and glacial meltwater input on FeHRcharacteristics,and elucidated the interaction between FeHRand total organic carbon(TOC),and its implications for the sedimentary environment.Basically,the CIA(52.7±1.46)and FeHR/FeT ratio(0.20±0.02)are higher in the eastern Ross Sea than the western(45.4±2.73 and 0.17±0.01),probably resulting from the selective enrichment of fine-grained materials subjected to intense chemical weathering under low sedimentation rates.Interestingly,the CIA(37.6±5.45)is lowest,but FeHR/FeT ratio(0.25±0.01)is highest in the southwestern Ross Sea,mainly due to igneous bedrock,katabatic winds and glacial meltwater input in a weakly weathered environment.Relative high TOC/FeHRratios(1.29±0.30 and 1.04±0.70)in the southwestern and western Ross Sea indicate a sedimentary environment with high primary production and exogenous FeHRinputs.While,relative low TOC/FeHRratio(0.63±0.13)in the eastern Ross Sea indicates the dual control of strong TOC remineralization and intense chemical weathering-derived FeHRproduction.The chemical weathering intensity is the primary controlling factor for FeHRcontent and composition in marine sediments globally,according to the significant positive correlations between FeHR/FeT ratios and CIA values(r=0.80)as well as FeT content(r=0.57).The unique glacial meltwater and lithological characteristics of the Antarctic region can significantly influence local FeHR/FeT ratio,thereby regulating bioavailable Fe supply and TOC preservation.This finding provides new regional constraints for understanding iron-carbon coupling processes in polar regions.展开更多
The settling of particulate carbon in seawater is a key component of the ocean carbon cycle. We deployed a set of sediment trap in the polynya of Prydz Bay from December 2010 to December 2011 to investigate the season...The settling of particulate carbon in seawater is a key component of the ocean carbon cycle. We deployed a set of sediment trap in the polynya of Prydz Bay from December 2010 to December 2011 to investigate the seasonal variations in particle fluxes. There was a clear seasonal variation in the particle fluxes, with maximum and minimum fluxes recorded during the summer and winter, respectively. The average total flux over the sampling period was 193.58 mg m^(-2)d^(-1), and the average fluxes of organic carbon(C_(org)), inorganic carbon(C_(inorg)), and biogenic silica(Si_(bio)) were 721.78, 28.67, and 2382.80 μmol m^(-2) d^(-1), respectively. Si_(bio)was the main contributor to the total mass flux, and strongly correlated with C_(org). The high Si_(bio)/C_(org)molar ratios(>1) suggest that C_(org)was transported to deep sea in association with Si_(bio). By comparing remote sensing data of sea ice and chlorophyll in the upper water column, we found that the dynamics of carbon fluxes were closely related to changes in sea ice. Algae in sea ice may have a key role in biological pump processes in early summer. Apart from the ice algae bloom period, variations in carbon fluxes generally corresponded with phytoplankton blooms in the upper water. The ballast effect controlled the particle settling velocity and the efficiency of the biological pump. Sea ice rafts initiated the first particle export event and enhanced the particle settling efficiency during melting period. As diatoms might become less dominant in the ice-free area, sea ice loss may cause the efficiency of the biological pump efficiency to decrease over the long term.展开更多
In this work,a sialic acid(SA)-imprinted thermo-responsive hydrogel layer was prepared for selective capture and release of cancer cells.The SA-imprinting process was performed at 37℃ using thermo-responsive function...In this work,a sialic acid(SA)-imprinted thermo-responsive hydrogel layer was prepared for selective capture and release of cancer cells.The SA-imprinting process was performed at 37℃ using thermo-responsive functional monomer,thus generating switchable SA-recognition sites with potent SA binding at 37℃and weak binding at a lower temperature(e.g.,25℃).Since SA is often overexpressed at the glycan terminals of cell membrane proteins or lipids,the SA-imprinted hydrogel layer could be used for selective cancer cell recognition.Our results confirmed that the hydrogel layer could efficiently capture cancer cells from not only the culture medium but also the real blood samples.In addition,the captured cells could be non-invasively released by lowing the temperature.Considering the non-invasive processing mode,considerable capture efficiency,good cell selectivity,as well as the more stable and durable SA-imprinted sites compared to natural antibodies or receptors,this thermo-responsive hydrogel layer could be used as a promising and general platform for cell-based cancer diagnosis.展开更多
Simulation of self-recovery and diversity of natural photonic crystal(PC)structures remain great challenges for artificial PC materials.Motivated by the dynamic characteristics of PC nanostructures,here,we present a n...Simulation of self-recovery and diversity of natural photonic crystal(PC)structures remain great challenges for artificial PC materials.Motivated by the dynamic characteristics of PC nanostructures,here,we present a new strategy for the design of hydrogel-based artificial PC materials with reversible interactions in the periodic nanostructures.The dynamic PC hydrogels,derived from self-assembled microgel colloidal crystals,were tactfully constructed by reversible crosslinking of adjacent microgels in the ordered structure via phenylboronate covalent chemistry.As proof of concept,three types of dynamic colloidal PC hydrogels with different structural colors were prepared.All the hydrogels showed perfect self-healing ability against physical damage.Moreover,dynamic crosslinking within the microgel crystals enabled shear-thinning injection of the PC hydrogels through a syringe(indicating injectability or printability),followed by rapid recovery of the structural colors.In short,in addition to the great significance in biomimicry of self-healing function of natural PC materials,our work provides a facile strategy for the construction of diversified artificial PC materials for different applications such as chem-/biosensing,counterfeit prevention,optical display,and energy conversion.展开更多
Porphyrinoid metal-organic frameworks(MOFs)with dual effective uranium uptake sites were synthesized through combined insitu and post-synthetic method.The MOF10@5 demonstrates the uptake amount of uranium reaches 1476...Porphyrinoid metal-organic frameworks(MOFs)with dual effective uranium uptake sites were synthesized through combined insitu and post-synthetic method.The MOF10@5 demonstrates the uptake amount of uranium reaches 1476 mg/g under visiblelight irradiation.The PN-MOF10@5 with dual uranyl uptake sites yields the amount of extracting uranyl of 1590 mg/g under visible-light irradiation.The density functional theory(DFT)calculations reveal strong interaction between uranyl and dual uranyl effective active sites.These MOFs demonstrate a powerful synthesis strategy for uranium extraction materials with dual effective active sites.展开更多
基金The National Polar Special Program under contract Nos IRASCC 01-01-02 and IRASCC 02-02the National Natural Science Foundation of China under contract Nos 41976228,42276255,41976227,42176227,and 42076243+1 种基金the International Cooperation Key Project of the Ministry of Science and Technology under contract No.2022YFE0136500the Scientific Research Fund of the Second Institute of Oceanography,Ministry of Natural Resources,under contract Nos JG2011,JG2211,JG2013,and JG1805.
文摘Polynyas and their adjacent seasonal ice zones(SIZs)represent the most productive regions in the Southern Ocean,supporting unique food webs that are highly sensitive to climate change.Understanding the dynamics of phytoplankton and the carbon pool in these areas is crucial for assessing the role of the Southern Ocean in global carbon cycling.During the late stage of an algal bloom,seawater samples at 14 stations were collected in the Amundsen Sea Polynya(ASP)and adjacent SIZ.Using nutrients,phytoplankton pigments,organic carbon(OC),remote sensing data,and physicochemical measurements,as well as CHEMTAX model simulations,we investigated the response of the phytoplankton crops,taxonomic composition,and OC pool to environmental factors.Our analyses revealed that hydrodynamic regimes of the polynya,adjacent SIZs and open sea were regulated by the regionally varying intrusion of Circumpolar Deep Water,photosynthetically active radiation and sea ice melt water.The ASP exhibited the highest seasonal nutrient utilization rates[ΔN=(1059±386)mmol/m^(2),ΔP=(50±17)mmol/m^(2) andΔSi=(956±904)mmol/m^(2)],while the open sea had lower rates.The integrated chlorophyll a(Chl a)concentration at depths of 0–200 m ranged from 20.4 mg/m^(2) to 1420.0 mg/m^(2) and peaked in the polynya.In the study area,Haptophytes Phaeocystis antarctica was the dominant functional group(34%±27%),and diatoms acted as a secondary contributor(23%±14%).The major functional group and particulate OC(POC)contributor varied from diatoms(36%±12%)in the open sea to haptophytes(48%±31%)in the polynya waters.Strong light conditions and microelement limitations promoted the dominance of P.antarctica(low Fe forms)dominance in the ASP.The strong correlations between the POC and Chl a depth-integrated concentration suggest that the POC was primarily derived from phytoplankton,while dissolved OC(DOC)was influenced by consumer activity and water mass transport.In addition,the transport of OC in the upper 200 m of the water column within the ASP was quantified,revealing the predominantly westward fluxes for both DOC[9.0 mg/(m^(2)·s)]and POC[7.2 mg/(m^(2)·s)].The latitudinal transport exhibited the northward transport of DOC[8.1 mg/(m^(2)·s)]and southward transport of POC[4.3 mg/(m^(2)·s)]movement.These findings have significant implications for enhancing our understanding of how hydrodynamics influence OC cycling in polynya regions.
基金The National Key Research and Development Program of China under contract No.2022YFE0136500the Scientific Research Fund of the Second Institute of Oceanography,Ministry of Natural Resources,under contract Nos JG2212 and JG2211+2 种基金the National Natural Science Foundation of China under contract Nos 42276255,41976228,and 42176227the National Polar Special Program“Impact and Response of Antarctic Seas to Climate Change”under contract Nos IRASCC 01-01-02 and IRASCC 02-02the China Scholarship Council under contract No.201704180017.
文摘The melting of seasonal sea ice in Antarctica plays a pivotal role in the region’s carbon cycle,influencing global carbon storage and the exchange of carbon between the atmosphere and the ocean.However,the impact of variability in the timing of seasonal sea ice retreat on the flux and composition of sinking particulate matter remains to be elucidated.In this study,we deployed sediment traps in Prydz Bay during the austral summers of 2019/2020 and 2020/2021,noting that sea ice melting occurred approximately one and a half months earlier in the former summer compared to the latter.We analyzed sediment trap data,which included total mass flux(TMF),particulate organic carbon(POC),biogenic silica(BSi),particulate inorganic carbon,and lithogenic particle(Litho)fluxes,as well as the stable isotopesδ^(13)C andδ^(15)N of particulate organic matter(POM).Additionally,we incorporated remote sensing data on sea ice concentration and chlorophyll a.This dramatic delay in sea ice melting timing could result in a significant increase in TMF,BSi and POC fluxes in the summer of 2020/2021 compared to 2019/2020.Elevated BSi fluxes and more ^(13)C-depleted POC in the austral summer of 2020/2021 suggest that the delayed melting of sea ice may have stimulated the productivity of centric diatoms.Furthermore,the higher BSi/POC ratio and more negativeδ^(15)N values of POM,along with a reduced presence of krill in the traps,indicate a diminished grazing pressure from zooplankton,which collectively enhanced the sedimentation efficiency of POC during the austral summer of 2020/2021.These findings highlight the critical role of sea ice melting timing in regulating productivity,flux and composition of sinking particulate matter in the Prydz Bay ecosystem,with significant implications for carbon cycling in polar oceans.
基金supported by the National Natural Science Foundation of China(22478167,22278419)the College Students Innovative Practice Plan of Jiangsu University(202410299160Y)+2 种基金the Youth Talent Cultivation Plan of Jiangsu Universitythe Key Core Technology Research(Social Development)Foundation of Suzhou(2023ss06)Collaborative Innovation Center for Water Treatment Technology and Materials and the Special Fund of Henan Key Laboratory of Water Pollution Control and Rehabilitation Technology(CJSZ2024010).
文摘Catalytic oxidation of biomass-derived 5-hydroxymethylfurfural(HMF)to 2,5-furandicarboxylic acid(FDCA,an alternative bioplastic monomer to petroleum-derived terephthalic acid),has been identified as an important biomass conversion reaction in bio-based polyester industry.However,it is still challenging to acquire a high FDCA yield from the selective oxidation of HMF at low temperatures.Herein,a ternary metal-based catalyst was prepared by loading AuPdPt noble metal nanoparticles on the oxygen-rich vacancy titanium dioxide layer deposited on natural clay mineral halloysite nanotubes(HNTs),and the catalytic activity was examined for air-oxidation of HMF to FDCA in water at ambient temperature(30℃).By adjusting the Au/Pd/Pt ratio,a 93.6%FDCA yield was achieved with the optimal Au_(0.5)Pd_(0.2)Pt_(0.3)/TiO_(2)@HNTs catalyst,which revealed an impressive FDCA formation rate of 67.58 mmol g^(-1)h^(-1)and an excellent TOF value of 17.54 h^(-1)under normal air pressure at 30℃,surpassing the performance of mono-and bimetallic-based catalysts.Theoretical calculation and catalytic performance study clarified the structure-activity relationship.It was found that the ternary metal and oxygen vacancies revealing synergistic enhancement of ambient temperature catalyzed HMF air-oxidation via electronic structure tuning and adsorption intensification.DFT and kinetics study demonstrated that the presence of ternary metal significantly improved the adsorption capacity of substrate and enhanced the rate-determining step of the key intermediate 5-hydroxymethyl-2-furanocarboxylic acid(HMFCA)oxidation when compared to mono-and bimetal.Additionally,the TiO_(2)@HNTs support with high oxygen vacancy concentration facilitated the adsorption of oxygen,synergistically working with the ternary metal to activate and low the energy barriers for the generation of superoxide radical,thus enhancing the FDCA formation.This work offers a novel strategy for designing ternary metal-based catalysts for low-energy catalytic oxidation reactions.
基金The National Polar Special Program“Impact and Response of Antarctic Seas to Climate Change”under contract Nos IRASCC 01-01-02 and IRASCC 02-02the National Key Research and Development Program of China under contract No.2022YFE0136500+1 种基金the National Natural Science Foundation of China(NSFC)under contract Nos 41976228,42276255 and 42176227the Scientific Research Fund of the Second Institute of Oceanography under contract Nos JG2011,JG2211 and JG2013.
文摘Nutrient uptake status dominates phytoplankton biomass and community structure in the Southern Ocean during austral summer,yet how nutrient utilization variability responds to phytoplankton community succession is still unclear,partly due to lack of data spanning the entire summer.In this study,nitrate,phosphate,and silicate combined with temperature,salinity,and apparent oxygen utilization(AOU)were analyzed along 45°E in the Cosmonaut Sea during December 2019,January 2021,and February 2022.The variations in nutrient utilization in the euphotic layer were studied using biogeochemical tracers,and seasonal nutrient depletion was also estimated.The results showed that nutrient distribution varied significantly from December to February.Significant positive correlations were observed for nitrate and silicate concentrations with salinity and AOU,indicating that nutrient distributions were mainly influenced by water mass and phytoplankton production.Increasing∆[N*]and decreasing∆[Si*]in the upper 50 m were observed south of 63.5°S from December to February,which possibly contributed to a progressive shift in dominant phytoplankton population from Phaeocystis antarctica to diatoms.The seasonal nutrient depletion generally increased from December to February.Moreover,the consumption of silicate substantially increased compared to nitrate,indicating that the abundance of diatoms was increasing with time during the austral summer.Our observations suggest that nutrient utilization status is closely related to phytoplankton community structure in the euphotic layer of the Cosmonaut Sea.
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(22078132,22108103,and U22A20413)the Open Funding Project of the National Key Labora-tory of Biochemical Engineering(2021KF-02)+3 种基金China Postdoctoral Science Foundation(2021M691301)Jiangsu Key Research and Development Program(BE2022356)the Postdoctoral Fellowship Program of China Postdoctoral Science Foundation(CPSF)(GZ20230989)Jiangsu Agricultural Independent Innovation Fund Project(CX(21)3079).
文摘Expanding the specific surface area of substrates and carrying out precise surface engineering of imprinted nanocavities are crucial methods for enhancing the identification efficiency of molecularly imprinted polymers(MIPs).To implement this synergistic strategy,bioinspired surface engineering was used to incorporate dual covalent receptors via precise post-imprinting modifications(PIMs)onto mesoporous silica nanosheets.The prepared sorbents(denoted as‘‘D-PMIPs”)were utilized to improve the specific identification of adenosine 5-monophosphate(AMP).Significantly,the mesoporous silica nanosheets possess a high surface area of approximately 498.73 m^(2)·g^(-1),which facilitates the formation of abundant specific recognition sites in the D-PMIPs.The dual covalent receptors are valuable for estab-lishing the spatial orientation and arrangement of AMP through multiple cooperative interactions.PIMs enable precise site-specific functionalization within the imprinted cavities,leading to the tailor-made formation of complementary binding sites.The maximum number of high-affinity binding sites(Nmax)of the D-PMIPs is 39.99 lmol·g^(-1),which is significantly higher than that of imprinted sorbents with a sin-gle receptor(i.e.,S-BMIPs or S-PMIPs).The kinetic data of the D-PMIPs can be effectively described by a pseudo-second-order model,indicating that the main binding mechanism involves synergistic chemisorption from boronate affinity and the pyrimidine base.This study suggests that using dual cova-lent receptors and PIMs is a reliable approach for creating imprinted sorbents with high selectivity,allow-ing for the controlled engineering of imprinted sites.
基金financially supported by National Natural Science Foundation of China (21908085)Natural Science Foundation of Jiangsu Province, China (BK20190961)+2 种基金Postdoctoral Research Foundation of Jiangsu Province (2020Z291)Foundation from Marine Equipment and Technology Institute for Jiangsu University of Science and Technology, China (HZ20190004)High-tech Ship Research Project of the Ministry of Industry and Information Technology, China (No. [2017] 614)
文摘High applied thermal-stability and superior structural property for activated carbon adsorbent are extremely promising,which also is the determining short slab in volatile organic compounds(VOCs)adsorption applications.Herein,we develop the outstanding engineering carbon adsorbents from waste shaddock peel which affords greatly-enhanced thermal-stability and super structural property(S_(Lang)=4962.6 m2·g^(-1),Vmicro=1.67 cm^(3)·g^(-1)).Such character endows the obtained adsorbent with ultrahigh adsorption capture performance of VOCs specific to benzene(16.58 mmol·g^(-1))and toluene(15.50 mmol·g^(-1),far beyond traditional zeolite and activated carbon even MOFs materials.The structural expression characters were accurately correlated with excellent adsorption efficiency of VOCs by studying synthetic factor-controlling comparative samples.Ulteriorly,adsorption selectivity prediction at different relative humidity was demonstrated through DIH(difference of the isosteric heats),exceedingly highlighting great superiority(nearly sixfold)in selective adsorption of toluene compared to volatile benzene.Our findings provide the possibility for practical industrial application and fabrication of waste biomass-derived outstanding biochar adsorbent in the environmental treatment of threatening VOCs pollutants.
基金The program of Impact and Response of Antarctic Seas to Climate Change under contract No. IRASCC2020-2022(01-01-02 and 02-02)the National Natural Science Foundation of China under contract Nos 41976228, 41976227 and 41506223the Scientific Research Fund of the Second Institute of Oceanography under contract Nos JG1805, JG2011 and JG2013。
文摘The ecosystem of the sea region adjacent to the Antarctic Peninsula is undergoing remarkable physical and biological changes, in the context of global warming. However, understanding of the dynamics of phytoplankton taxonomic composition in this marginal ice zone remains unclear. In this study, seawater samples collected from 36 stations in the northeastern Antarctic Peninsula were analyzed for nutrients and phytoplankton pigments.Combining with CHEMTAX analysis, remote sensing data, and physicochemical measurements, we investigated the relationships between phytoplankton crops, taxonomic composition, and marine environmental drivers.Integrated chlorophyll a(Chl a) concentrations(200 m) varied from 8.9 mg/m^(2)to 64.2 mg/m^(2), with an average of(23.2±12.0) mg/m^(2)and higher phytoplankton biomass concentrated in the coastal region of South Orkney Island and South Shetland Island. Diatoms were the dominant functional group(63%±21%). Higher proportions of diatoms were associated with higher Chl a(r=0.40, p<0.01), stable water columns(r=0.20, p<0.01), higher Si/P ratios(r=0.34, p<0.01), higher photosynthetically active radiation intensity(r=0.64, p<0.01), and higher sea ice melt water contributions(MWC, r=0.20, p<0.01). Conversely, Phaeocystis antarctica contributed a smaller overall proportion(31%±18%) and was more concentrated in the offshore water masses(e.g., Philip Ridge and South Scotia Ridge) with lower light levels(r=-0.58, p<0.01), deeper mixed layer depths(r=0.17, p<0.05), higher nutrient concentrations(e.g., N, P, and Si, r>0.35, p<0.01), and lower MWC(r=-0.20, p<0.01). In comparison, the total contribution from green flagellates(4%±5%), cryptophyta(1%±3%), dinoflagellates(1%±4%), and cyanobacteria(1% ± 5%) was only 6%. In offshore regions with well-mixed water, less varied taxonomic composition and lower crops with a higher proportion of nanophytoplankton were observed. In contrast, significantly decreasing crops below the mixed layer depth was observed in water columns with strong stratification, where the dominant phytoplankter changed from diatoms to P. antarctica. These findings have important implications for better understanding the future dynamics of marine ecosystems in the sea area adjacent to the Antarctic Peninsula.
基金The Scientific Research Fund of the Second Institute of Oceanography under contract Nos JG2011 and JG1516the National Natural Science Foundation of China under contract No.41606090the National Basic Research Program(973 Program)of China under contract No.2015CB755904.
文摘Sediment collapse and subsequent lateral downslope migration play important roles in shaping the habitats and regulating sedimentary organic carbon(SOC)cycling in hadal trenches.In this study,three sediment cores were collected using a human-occupied vehicle across the axis of the southern Yap Trench(SYT).The total organic carbon(TOC)and total nitrogen(TN)contents,δ13C,radiocarbon ages,specific surface areas,and grain size compositions of sediments from three cores were measured.We explored the influence of the lateral downslope transport on the dispersal of the sediments and established a tentative box model for the SOC balance.In the SYT,the surface TOC content decreased with water depth and was decoupled by the funneling effect of the V-shaped hadal trench.However,the sedimentation(0.0025 cm/a)and SOC accumulation rates(∼0.038 g/(m^(2)·a)(in terms of OC))were approximately 50%higher in the deeper hadal region than in the abyssal region(0.0016 cm/a and∼0.026 g/(m^(2)·a)(in terms of OC),respectively),indicating the occurrence of lateral downslope transport.The fluctuating variations in the prokaryotic abundances and the SOC accumulation rate suggest the periodic input of surficial sediments from the shallow region.The similar average TOC(0.31%–0.38%),TN(0.06%–0.07%)contents,and SOC compositions(terrestrial OC(11%–18%),marine phytoplanktonic OC(45%–53%),and microbial OC(32%–44%))of the three sites indicate that the lateral downslope transport has a significant mixing effect on the SOC composition.The output fluxes of the laterally transported SOC(0.44–0.56 g/(m^(2)·a)(in terms of OC))contributed approximately(47%–73%)of the total SOC input,and this proportion increased with water depth.The results of this study demonstrate the importance of lateral downslope transport in the spatial distribution and development of biomes.
基金financially supported by the National Natural Science Foundation of China (22078132 and 22108103)Open Funding Project of the National Key Laboratory of Biochemical Engineering (2021KF-02)+3 种基金China Postdoctoral Science Foundation (2021M691301)Jiangsu Agricultural Independent Innovation Fund Project (CX(21)3079)Graduate Research Innovation Program of Jiangsu Province (KYCX20-3040)China Postdoctoral Science Foundation (2021M691301)。
文摘Molecularly imprinted polymers (MIPs) have great potential as adsorbents for selective adsorption and separation of nucleoside compounds,but effectively enhancing the affinity of recognition sites by adjusting the forces between template molecules and functional monomers remains an important challenge.In this work,a surface imprinting strategy was used to construct bowl-shaped molecularly imprinted composite sorbents (BHPN@MIPs) based on polydopamine (PDA) particles and have achieved selective separation and purification of 2'-deoxyadenosine (dA).Where by the base complementary pairing interaction of the combined template molecule d A and the pyrimidine functional monomer can enhance the preassembly force,and the hydrophilic bowl-shaped PDA can provide a larger storage space contact efficiency of d A in the test solution,causing the site utilization much higher and improving the kinetic adsorption performance.The equilibrium adsorption time and maximum adsorption capacity of60 min and 328.45μmol·g^(-1)were observed by static adsorption experiments,and the selectivity experimental results showed an imprinting factor IF of 1.30.After four adsorption–desorption cycles,the initial adsorption equilibrium adsorption capacity of BHPN@MIPs still retained 91.14%.By evaluating the selective adsorption of d A in spiked human serum solutions,BHPN@MIPs can be used to selectively enrich and analyze target d A in complex biological samples.
基金supported by the China Scholarship Council through a State-Sponsored Scholarship Program, NSF of China (No. 21307019)the Public Science and Technology Research Fund Projects of Ocean (No. 201505034)+2 种基金the Zhejiang Provincial Natural Science Foundation (Nos. LY14D060007 and LQ16D060006)National Key Research and Development Program (No. 2016YFC1402405)support from the Environment Research Center (ERC) at the Missouri University of Science and Technology, Rolla, Missouri, USA
文摘TiO2 nanoparticles（NPs） could adversely impact aquatic ecosystems. However, the aggregation of these NPs could attenuate this effect. In this work, the biological effects of TiO2 NPs on a marine microalgae Isochrysis galbana were investigated. The aggregation kinetics of TiO2 NPs under different conditions was also investigated to determine and understand these effects. Results showed that, though TiO2 NPs had no obvious impact on the size and reproducibility of algal cells under testing conditions, they caused a negative effect on algal chlorophyll, which led to a reduction in photosynthesis. Furthermore, fast aggregation of TiO2 NPs occurred under all conditions, especially at the pH close to the p Hzpc. Increasing ionic strength and NP concentration also enhanced the aggregation rate.The aggregation and the following sedimentation of TiO2 NPs reduced their adverse effects on I. galbana.
基金Supported by the China’s National Polar Special Program“Impact and Response of Antarctic Seas to Climate Change”(Nos.IRASCC 01-01-02,IRASCC 02-02)the Scientific Research Fund of the Second Institute of Oceanography(Nos.JG 2011,JG 2211,JG 2013,JG 1805)+1 种基金the National Natural Science Foundation of China(Nos.42276255,41976228,41976227)the International Cooperation Key Project of Ministry of Science and Technology(No.2022 YFE 0136500)。
文摘The ecosystems in Southern Ocean(SO)are undergoing significant changes in the context of climate change.To identify environment-phytoplankton feedbacks in SO,seawater samples were collected in the Cosmonaut Sea(CS)during the 37 th China Antarctic Research Expedition(Jan.2021)(CHINARE-37)and subjected to analysis of particulate organic carbon(POC)and phytoplankton pigments.The remote sensing data,CHEMTAX community compositional modeling analysis,and physicochemical measurements were combined to explore the spatial variation of phytoplankton crops,taxonomic composition,and their environmental drivers.Historical phytoplankton community data from the area were also compared against those of this study to investigate inter-annual community differences and their potential causes.The column-integrated POC and chlorophyll-a(Chl-a)concentrations were 12.0±4.9 g/m^(2) and 73.8±50.5 mg/m^(2),respectively.The two most dominant taxa were haptophyte that are adapted to high Fe availability(Hapt-HiFe,mainly Phaeocystis antarctica)and Diatoms-A(Phaeodactylum tricornutum)that contributed to 33%±25%and 24%±14%to the total phytoplankton crops,respectively.Through cluster analysis,the study area was divided into two regions dominated by Hapt-HiFe and Diatoms-A,respectively.Spatially,Hapt-HiFe was mainly concentrated in the southwest coastal area that featured low temperatures,low salinity,and shallow euphotic zones.The coastal region southwest of the southern boundary of the Antarctic circumpolar current was experiencing a bloom of Hapt-HiFe during the study period that significantly contributed to the POC pool and Chl-a concentrations(R=0.46,P<0.01;R=0.42,P<0.01).Besides,the dominance of Hapt-HiFe in the CS suggests a high biological availability of dissolved Fe that is primarily associated with inputs from sea ice melt and upwellings.
文摘The Southern Ocean breeds a special ecosystem.The evolution and adaptability of Antarctic marine organisms is a key research field of the Scientific Committee on Antarctic Research.The study of the Antarctic marine ecosystem is also one of the tasks of Chinese National Antarctic Research Expedition(CHINARE).However,the early investigations by Chinese scientists mainly focused on plankton and benthos,as well as their environmental variables.Since 2019,financially supported by National Polar Special Program“Impact and Response of Antarctic Seas to Climate Change”(IRASCC),the research objects have been gradually expanded to large marine animal,such as birds and mammals,and other related disciplines.
基金supported by Jiangsu Funding Program for Excellent postdoctoral Talent(2023ZB453 and 2023ZB108)National Natural Science Foundation of China(22306075 and 22108103)Hong Kong Environment and Conservation Fund(2022-127).
文摘The rapid expansion of the chemical and pharmaceutical industries has resulted in the introduction of various sources of micropollutants into the environment,posing threats to drinking water quality and public health.Membrane separation technology offers a promising solution with low energy use,high-quality effluent,and operational simplicity.Here,we developed fluffy layered double hydroxides(LDH)/graphene oxide(GO)2D membranes,specifically tannic acid-mediated LDH-GO/GO-TA composite membranes(LG/GT).The integration of GO nanosheets regulated the growth of LDH,enhancing electron transfer and adsorption-driven catalytic performance.This design enabled LDH-GO to activate peroxymonosulfate(PMS)and completely degraded Rhodamine B(RhB)within 10 min.The Gaussian calculation was combined with this finding,which could explain the catalytic self-cleaning in the separation process.The TA-mediated enhancement further increased the RhB rejection of LG/GT-7.5 to 99.23%.Additionally,the needle/sheet structure significantly improved permeance to 358.28 L m^(-2) h^(-1) bar^(-1),surpassing the L/GT-7.5 performance(e.g.338.53 L m^(-2) h^(-1) bar^(-1)),indicating superior pore formation and water mass transfer.The heterostructure between GO and LDH greatly improved cycling stability,with the membrane maintaining a permeance of 282.71 L m^(-2) h^(-1) bar^(-1) and a rejection of 97.97% despite 20 cycles.This work demonstrated the potential of fluffy layered LDH 2D membranes for enhanced wastewater treatment applications.These findings suggested significant potential for practical implementation in industrial wastewater treatment processes,offering a sustainable and efficient solution to water pollution challenges.
基金the National Natural Science Foundation of China(Grant Nos.22478162,22208128)the Natural Science Foundation of Jiangsu Province(Grant No.BK20210775)Jiangsu University Senior Talent Funding(Grant No.4111310025).
文摘MXenes,an extensive family of two-dimensional(2D)materials,have attracted significant attention across diverse fields owing to their exceptional biological,optoelectronic,mechanical,and chemical properties,enabling their application in numerous fields.Among these,photothermal water evaporation(PWE)has emerged as a particularly promising approach in wastewater treatment,driven by the escalating demand for fresh and pure water.Despite the development of various evaporators to address water scarcity,challenges such as low evaporation efficiency and limited scalability hinder their practical implementation.Over the past decade,MXenes have gained substantial interest owing to their unique elemental composition,porous structure,and surface terminations,which result in remarkable physical and chemical properties that depend on their synthesis methods.However,a key challenge in leveraging MXenes lies in their inherent instability,as they are prone to rapid oxidation upon exposure to air.Stabilizing pristine MXenes is,therefore,critical for their long-term application in PWE.This review highlights strategies to enhance the oxidation stability of MXenes through the incorporation of protective materials such as polymers,delignified wood(DW),and carbonaceous compounds,thereby improving their performance in PWE systems.Furthermore,this review delves into the development of MXene-based composite materials,exploring factors and mechanisms pertinent to their role in PWE.This comprehensive analysis provides valuable insights for researchers and practitioners in the field of wastewater treatment.
基金jointly supported by the National Key Research and Development Program of China(Grant No.2022YFE0136500)the National Natural Science Foundation of China(NSFC)(Grant No.41976228)+2 种基金the scientific research fund of Second Institute of Oceanography,MNR(Grant No.JG1805)the National Polar Special Program“Impact and Response of Antarctic Seas to Climate Change”(Grant Nos.IRASCC 01-01-02A and 02-02)the China Scholarship Council(Grant No.201704180017)。
文摘The highly reactive iron(FeHR)in marine sediments is a key driver of the iron-carbon coupled biogeochemical cycle.However,rare is known on its speciation and environmental regulation mechanisms in the climate-sensitive West Antarctic region.This study investigated the spatial distribution of FeHRcontent and composition in surface sediments of the Ross Sea,examined the synergistic regulatory mechanisms of chemical weathering intensity(quantified by the chemical index of alteration,CIA),bedrock properties and glacial meltwater input on FeHRcharacteristics,and elucidated the interaction between FeHRand total organic carbon(TOC),and its implications for the sedimentary environment.Basically,the CIA(52.7±1.46)and FeHR/FeT ratio(0.20±0.02)are higher in the eastern Ross Sea than the western(45.4±2.73 and 0.17±0.01),probably resulting from the selective enrichment of fine-grained materials subjected to intense chemical weathering under low sedimentation rates.Interestingly,the CIA(37.6±5.45)is lowest,but FeHR/FeT ratio(0.25±0.01)is highest in the southwestern Ross Sea,mainly due to igneous bedrock,katabatic winds and glacial meltwater input in a weakly weathered environment.Relative high TOC/FeHRratios(1.29±0.30 and 1.04±0.70)in the southwestern and western Ross Sea indicate a sedimentary environment with high primary production and exogenous FeHRinputs.While,relative low TOC/FeHRratio(0.63±0.13)in the eastern Ross Sea indicates the dual control of strong TOC remineralization and intense chemical weathering-derived FeHRproduction.The chemical weathering intensity is the primary controlling factor for FeHRcontent and composition in marine sediments globally,according to the significant positive correlations between FeHR/FeT ratios and CIA values(r=0.80)as well as FeT content(r=0.57).The unique glacial meltwater and lithological characteristics of the Antarctic region can significantly influence local FeHR/FeT ratio,thereby regulating bioavailable Fe supply and TOC preservation.This finding provides new regional constraints for understanding iron-carbon coupling processes in polar regions.
基金supported by the National Natural Science Foundation of China(Grant Nos.41406219,41576186&41506223)the Scientific Research Fund of the Second Institute of Oceanography,SOA(Grant No.JT1405)+2 种基金the Chinese Polar Environment Comprehensive Investigation&Assessment Programs(Grant No.CHINARE 01-04,04-01)the Chinese Arctic and Antarctic Administration Foundation(Grant No.20150302)the Scientific Research Project of Marine Public Welfare Industry of China(Grant No.201405031-04)
文摘The settling of particulate carbon in seawater is a key component of the ocean carbon cycle. We deployed a set of sediment trap in the polynya of Prydz Bay from December 2010 to December 2011 to investigate the seasonal variations in particle fluxes. There was a clear seasonal variation in the particle fluxes, with maximum and minimum fluxes recorded during the summer and winter, respectively. The average total flux over the sampling period was 193.58 mg m^(-2)d^(-1), and the average fluxes of organic carbon(C_(org)), inorganic carbon(C_(inorg)), and biogenic silica(Si_(bio)) were 721.78, 28.67, and 2382.80 μmol m^(-2) d^(-1), respectively. Si_(bio)was the main contributor to the total mass flux, and strongly correlated with C_(org). The high Si_(bio)/C_(org)molar ratios(>1) suggest that C_(org)was transported to deep sea in association with Si_(bio). By comparing remote sensing data of sea ice and chlorophyll in the upper water column, we found that the dynamics of carbon fluxes were closely related to changes in sea ice. Algae in sea ice may have a key role in biological pump processes in early summer. Apart from the ice algae bloom period, variations in carbon fluxes generally corresponded with phytoplankton blooms in the upper water. The ballast effect controlled the particle settling velocity and the efficiency of the biological pump. Sea ice rafts initiated the first particle export event and enhanced the particle settling efficiency during melting period. As diatoms might become less dominant in the ice-free area, sea ice loss may cause the efficiency of the biological pump efficiency to decrease over the long term.
基金supported by the National Key Research and Development Program of China(2019YFA0112000 and 2016YFC1100203)the National Natural Science Foundation of China(21875092,81925027,21706099 and 81471790)+2 种基金the China Postdoctoral Science Foundation(2016M601745)the Innovation and Entrepreneurship Program of Jiangsu Province,the“Six Talent Peaks”program of Jiangsu Province(2018-XCL-013)the Priority Academic Program Development of Jiangsu Higher Education Institutions.
文摘In this work,a sialic acid(SA)-imprinted thermo-responsive hydrogel layer was prepared for selective capture and release of cancer cells.The SA-imprinting process was performed at 37℃ using thermo-responsive functional monomer,thus generating switchable SA-recognition sites with potent SA binding at 37℃and weak binding at a lower temperature(e.g.,25℃).Since SA is often overexpressed at the glycan terminals of cell membrane proteins or lipids,the SA-imprinted hydrogel layer could be used for selective cancer cell recognition.Our results confirmed that the hydrogel layer could efficiently capture cancer cells from not only the culture medium but also the real blood samples.In addition,the captured cells could be non-invasively released by lowing the temperature.Considering the non-invasive processing mode,considerable capture efficiency,good cell selectivity,as well as the more stable and durable SA-imprinted sites compared to natural antibodies or receptors,this thermo-responsive hydrogel layer could be used as a promising and general platform for cell-based cancer diagnosis.
基金support from the National Key Research and Development Program of China(2019YFA0112000)the National Natural Science Foundation of China(21875092,21706099,and 91649204)+5 种基金the start-up fund(1-ZE7S)central research fund(G-YBWS)from the Hong Kong Polytechnic University,the China Postdoctoral Science Foundation funded project(2018M642174)the Postdoctoral Science Foundation of Jiangsu Province(2019K145)the Natural Science Foundation of Jiangsu Province(BK20160056 and BK20160491)the Innovation and Entrepreneurship Program of Jiangsu Provincethe Six Talent Peaks Project in Jiangsu Province(2018-XCL-013).
文摘Simulation of self-recovery and diversity of natural photonic crystal(PC)structures remain great challenges for artificial PC materials.Motivated by the dynamic characteristics of PC nanostructures,here,we present a new strategy for the design of hydrogel-based artificial PC materials with reversible interactions in the periodic nanostructures.The dynamic PC hydrogels,derived from self-assembled microgel colloidal crystals,were tactfully constructed by reversible crosslinking of adjacent microgels in the ordered structure via phenylboronate covalent chemistry.As proof of concept,three types of dynamic colloidal PC hydrogels with different structural colors were prepared.All the hydrogels showed perfect self-healing ability against physical damage.Moreover,dynamic crosslinking within the microgel crystals enabled shear-thinning injection of the PC hydrogels through a syringe(indicating injectability or printability),followed by rapid recovery of the structural colors.In short,in addition to the great significance in biomimicry of self-healing function of natural PC materials,our work provides a facile strategy for the construction of diversified artificial PC materials for different applications such as chem-/biosensing,counterfeit prevention,optical display,and energy conversion.
基金supported by the National Natural Science Foundation of China(No.22301108)the Project Startup Foundation for Distinguished Scholars of Jiangsu University(No.4111310026).
文摘Porphyrinoid metal-organic frameworks(MOFs)with dual effective uranium uptake sites were synthesized through combined insitu and post-synthetic method.The MOF10@5 demonstrates the uptake amount of uranium reaches 1476 mg/g under visiblelight irradiation.The PN-MOF10@5 with dual uranyl uptake sites yields the amount of extracting uranyl of 1590 mg/g under visible-light irradiation.The density functional theory(DFT)calculations reveal strong interaction between uranyl and dual uranyl effective active sites.These MOFs demonstrate a powerful synthesis strategy for uranium extraction materials with dual effective active sites.
