Investigating structural and hydroxyl group effects in electrooxidation of alcohols to value-added products by solid-acid electrocatalysts is essential for upgrading biomass alcohols.Herein,we report efficient electro...Investigating structural and hydroxyl group effects in electrooxidation of alcohols to value-added products by solid-acid electrocatalysts is essential for upgrading biomass alcohols.Herein,we report efficient electrocatalytic oxidations of saturated alcohols(C_(1)-C_(6))to selectively form formate using Ni Co hydroxide(Ni Co-OH)derived Ni Co_(2)O_(4)solid-acid electrocatalysts with balanced Lewis acid(LASs)and Brønsted acid sites(BASs).Thermal treatment transforms BASs-rich(89.6%)Ni Co-OH into Ni Co_(2)O_(4)with nearly equal distribution of LASs(53.1%)and BASs(46.9%)which synergistically promote adsorption and activation of OH-and alcohol molecules for enhanced oxidation activity.In contrast,BASs-enriched Ni Co-OH facilitates formation of higher valence metal sites,beneficial for water oxidation.The combined experimental studies and theoretical calculation imply the oxidation ability of C1-C6alcohols increases as increased number of hydroxyl groups and decreased HOMO-LUMO gaps:methanol(C_(1))<ethylene glycol(C_(2))<glycerol(C3)<meso-erythritol(C4)<xylitol(C5)<sorbitol(C6),while the formate selectivity shows the opposite trend from 100 to 80%.This study unveils synergistic roles of LASs and BASs,as well as hydroxyl group effect in electro-upgrading of alcohols using solid-acid electrocatalysts.展开更多
Large-scale CO_(2)emissions have exacerbated the greenhouse effect,reinforcing the critical need for efficient CO_(2)mitigation methods.Plasma-catalytic technology enables CO_(2)conversion under mild conditions,especi...Large-scale CO_(2)emissions have exacerbated the greenhouse effect,reinforcing the critical need for efficient CO_(2)mitigation methods.Plasma-catalytic technology enables CO_(2)conversion under mild conditions,especially for CO_(2)methanation(the Sabatier reaction),which has attracted significant attention due to its economic benefits and the potential for safe energy transportation via existing natural gas pipelines.The development of high-performance CO_(2)methanation catalysts remains an ongoing and long-term objective,and there is a lack of adequate in-situ characterization techniques to investigate the mechanisms.This study focuses on the Ni/La_(2)O_(3)(LN)catalyst and introduces two CO_(2)activation strategies through F and Na modifications:the Ni-Ov-Ni site activation with electron transfer from Ni0 under low-power conditions and basic site activation under high-power conditions.The LN-NaF catalysts enhance CO_(2)methanation activity across the entire power range compared to LN,achieving a CO_(2)conversion of 86.3%and CH4 selectivity of 99.4%.Additionally,LN-F(h)reaches a CH4 yield 4.15 times higher than that of LN at low power.Furthermore,in-situ diffuse reflectance infrared Fourier transform(DRIFT)spectroscopy with a self-made reactor are performed under plasma-catalytic conditions to reveal the CO_(2)adsorption and conversion mechanisms,indicating that different dopants(F,Na,and NaF)exhibit promoting effects on different intermediates,resulting in variations in CO_(2)methanation activity.This study provides valuable insights for improving catalyst performance and a thorough comprehension of mechanisms in CO_(2)methanation.展开更多
Peroxymonosulfate(PMS)-based advanced oxidation technology has been proven to be a viable option for the decontamination of organic pollutants from water bodies.Advanced catalyst design is essential to this technology...Peroxymonosulfate(PMS)-based advanced oxidation technology has been proven to be a viable option for the decontamination of organic pollutants from water bodies.Advanced catalyst design is essential to this technology.Herein,a vanadium-doped LaFeO_(3) perovskite(LFO-V)featuring asymmetric Fe-O-V sites was rationally designed.Thanks to orbital electron interaction between Fe and V atoms,the modified electronic structure elevated electron density near the Fermi energy level while reducing the energy barrier toward effective PMS activation.This facilitated concurrent PMS reduction at the Fe sites to generate SO_(4)^(·-)and·OH(57.7%),and PMS oxidation at V sites to produce ^(1)O_(2)(42.3%).The LFO-V/PMS system demonstrated excellent tetracycline(TC)degradation performance with a 2-fold enhancement in rate constant compared to that of pristine LFO.Further,the LFO-V maintained long-term stability,and the toxicity of degradation intermediates was evaluated through microbial metabolomics.This work establishes an effective route to regulate the PMS activation pathways through precise electronic structure modulation,advancing the rational design of advanced Fenton-like catalysts.展开更多
Under earthquake action, different site conditions have a notable impact on the dynamic response of high-speed railway bridges after earthquakes, which in turn poses a threat to the running stability of trains in the ...Under earthquake action, different site conditions have a notable impact on the dynamic response of high-speed railway bridges after earthquakes, which in turn poses a threat to the running stability of trains in the post-earthquake period. Therefore, establishing a calculation method for the post-earthquake train speed threshold that considers the influence of different site characteristics is of great engineering significance. Taking the CRTS Ⅲ slab track as the research object, this study is based on the track irregularity root mean square rate(TRR), which the authors proposed earlier to quantify the track regularity level. Using the nonlinear least squares fitting method, the mapping relationship between the TRR and the postearthquake train running performance indicators on bridges is established. Furthermore, the influence of laws governing site categories and train speeds on post-earthquake train running performance on bridges is analyzed, and a train speed threshold for bridges based on running performance under random site conditions is proposed. The research results indicate that all train running performance indicators increase significantly with the increase of train operating speed;different site categories have a significant impact on post-earthquake track residual deformation and train running stability. The greater the amplitude of postearthquake track alignment residual deformation, the lower the threshold for the stable running speed of trains after the earthquake, with the speed threshold decreasing by up to 20%. The research outcomes can provide technical references for the post-earthquake safe operation and maintenance of high-speed railway bridges under complex site conditions, as well as the formulation of targeted train speed control schemes.展开更多
Oxidative magnetization has attracted great attention as an efficient strategy for modulating physiochemical properties of magnetic biochar.In this paper,a K_(2)FeO_(4)-involving hydrothermal oxidative magnetization w...Oxidative magnetization has attracted great attention as an efficient strategy for modulating physiochemical properties of magnetic biochar.In this paper,a K_(2)FeO_(4)-involving hydrothermal oxidative magnetization was explored to regulate multiple micro-structures for manufacture magnetic hydrochar(MHC)for Fenton-like degradation of tetracycline in aqueous solution.Diverse shapes of Fe_(3)O_(4) and nano zero-valent iron(nZVI)were doped with abundant oxygen containing groups and persistent free radicals(PFRs).Multiple catalysis sites including iron species,PFRs,oxygen containing groups,and graphite defects contributed to accelerate the Fenton-like degradation with synergistic effect.Notably,MHC achieved a tetracycline removal rate of 99% within 60 min at 50 mg/L,with a total organic carbon(TOC)removal rate of 35%.Furthermore,after four cycles of reuse,the degradation efficiency slightly decreased to 93%.This study highlights the potential of magnetic hydrochar with multiple catalytic sites in the effective and sustainable degradation of pollutants.展开更多
Single atom catalysts supported by two-dimensional(2D)materials,including graphene,g-C_(3)N_(4),and graphdiyne,ex-hibit promising electrocatalytic nitrogen reduction reaction(NRR)activity.Nevertheless,sometimes theore...Single atom catalysts supported by two-dimensional(2D)materials,including graphene,g-C_(3)N_(4),and graphdiyne,ex-hibit promising electrocatalytic nitrogen reduction reaction(NRR)activity.Nevertheless,sometimes theoretical works failed to predict the high activity of NRR of single atom cat-alysts,especially for Fe,Co,Mn,Cu,Ru.In this work,based on DFT calculations,it is suggested that dual-atom sites on N doped graphene(M_(2)@N-graphene)rather than single-atom sites are more likely to be the active sites for NRR.Notably,Fe_(2)@N_(3),Co_(2)@N_(2),Mn_(2)@N_(2),Cu_(2)@N_(1),and Ru_(2)@N_(3)endow the best catalytic activity with corresponding limiting potentials of-0.26,-0.18,-0.17,-0.39,and-0.30 V,re-spectively.Furthermore,on g-C_(3)N_(4)and graphdiyne,triple-atom sites(TAS,M_(3))such as Ru_(3)(Co_(3))@g-C_(3)N_(4)and Ru_(3)(Rh_(3))@graphdiyne are expected to exhibit higher stability and NRR catalytic performance than single-atom sites(SAS)and dual-atom sites(DAS),with corresponding limiting potentials of-0.28,-0.48,-0.24,and-0.23 V.The calculated results with the corresponding experimental potentials indicate that the origin of superior NRR ac-tivity observed in experiments may be contributed by M_(2)or M_(3)on 2D materials.This study provides an in-depth investigation into real active NRR sites of metal atoms supported on 2D materials and contributes to the design of effective NRR catalysts.展开更多
Molecular recognition of bioreceptors and enzymes relies on orthogonal interactions with small molecules within their cavity. To date, Chinese scientists have developed three types of strategies for introducing active...Molecular recognition of bioreceptors and enzymes relies on orthogonal interactions with small molecules within their cavity. To date, Chinese scientists have developed three types of strategies for introducing active sites inside the cavity of macrocyclic arenes to better mimic molecular recognition of bioreceptors and enzymes.The editorial aims to enlighten scientists in this field when they develop novel macrocycles for molecular recognition, supramolecular assembly, and applications.展开更多
This research aimed to obtain accurate estimates of the productivity of eucalyptus plantations under different climate change scenarios without the need for additional fieldwork.Thus,we used tree growth data from 1,10...This research aimed to obtain accurate estimates of the productivity of eucalyptus plantations under different climate change scenarios without the need for additional fieldwork.Thus,we used tree growth data from 1,102research plots,existing spatially continuous environmental data,and the random forest(RF) algorithm to construct raster-based models.We constructed models to predict site index(SI) at landscape scale(250m·pixel^(-1)),which is useful for planning purposes and for analyzing the effect of climate change on productivity,and at forest plot scale(resolutions of 10,25,50,and 100 m-pixel^(-1)),which is essential for predicting plantation yields.All models explained~50% of site index variability,as is usual in this type of study.We found that the different spatial resolutions of predictor variables did not affect the amount of variability explained.This finding may be due to two opposing effects on the explained variability at finer scales:a positive effect,as finer scales enable capture of microscale landform variability through a high-resolution digital elevation model(DEM),and a negative effect due to the introduction of "noise" when downscaling the climatic and lithological information from coarser scales.Elevation and the climatic variables(mainly temperature) were the most important predictor variables:For every 100 m-increase in elevation,the productivity decreased by on average 0.3-0.9 m of site index(1-1.3 m^(3)·ha^(-1)·year^(-1) of maximum mean annual increment in volume) and for each degree-Celsiusincrease in annual mean temperature,productivity increased by about 2.2 m in site index(3 m^(3)·ha^(-1)·year^(-1)of maximum mean annual increment in volume).Due to the forecasted increase in temperatures under climate change,productivity is expected to increase significantly in Eucalyptus globulus plantations in northern Spain in the coming decades,by between 1.68% and 3.38% of the current average site index under the most pessimistic climate change scenario and between 1.79% and 2.48% of the current average site index for the moderate scenario.We conclude that currently available spatially continuous environmental data can be used to develop accurate raster data models for predicting site productivity for E.globulus without the need for fieldwork.The spatially explicit maps produced in the study provide support to forest planners,forest managers,private landowners and politicians,enabling well-founded decisions to be made regarding selection of the best sites for afforestation and providing accurate yield predictions for the plantations.展开更多
Cu metal and its oxides have attracted much attention for photocatalytic CO_(2)reduction reaction(CO_(2)RR),but the stability and effects of Cu oxidation states on CO_(2)RR are not fully understood.Cu^(x+)/Cu^(0)-load...Cu metal and its oxides have attracted much attention for photocatalytic CO_(2)reduction reaction(CO_(2)RR),but the stability and effects of Cu oxidation states on CO_(2)RR are not fully understood.Cu^(x+)/Cu^(0)-loaded graphitic carbon nitride(g-C_(3)N_(4))heterojunctions(Cu-CuO_(x)/g-C_(3)N_(4))are fabricated via a stepwise calcination method for efficient photocatalytic CO_(2)RR.Cu_(2)O is the main component of Cu-CuO_(x)and the mixed valence Cu includes Cu^(0),Cu^(+),and Cu^(2+),which play the role of charge trapping sites and redox catalytic centers during the photocatalytic CO_(2)RR process.The main products were CO and CH_(4)for the CO_(2)RR with production rates of 14.45 and 0.66μmol g^(-1)h^(-1)for CO and CH_(4),which were higher than those for g-C_(3)N_(4)and Cu-CuO_(x),respectively.This photocatalytic CO_(2)RR performance is attributed to the ultrafast switching of“Cu^(x+)−Cu^(0)”and e_(CB^(−))/h_(VB^(+))trapping transformation in Cu-CuO_(x)benefited from the built-in IEF between Cu-CuO_(x)and g-C_(3)N_(4),increasing the efficient photogenerated e_(CB^(−)),and enabling the stability of Cu-CuO_(x)/g-C_(3)N_(4).Cu^(x+)adsorbed by H_(2)O works as the electron trapping site to change to Cu^(0)and switch to the hole trapping site;Cu^(0)works as the hole trapping site to change to Cu^(x+)and switch to the electron trapping site,causing the CO_(2)RR of the adsorbed CO_(2).Moreover,the coordinated Cu^(0)and Cu^(+)species facilitate the activation of the adsorbed CO_(2)and^(∗)CO generation,these adsorbed^(∗)CO on Cu^(0)and Cu^(+)detected by in-situ DRIFTS quickly transformed to^(∗)CHO with a lower energy barrier benefited from the mixed Cu^(0)/Cu^(+)active sites during CORR to produce CH_(4).This finding provides a new insight into the influence of mixed valence Cu during photocatalytic CO_(2)RR.展开更多
Controlled photocatalytic conversion of CO_(2) into premium fuel such as methane(CH4)offers a sustainable pathway towards a carbon energy cycle.However,the photocatalytic efficiency and selectivity are still unsatisfa...Controlled photocatalytic conversion of CO_(2) into premium fuel such as methane(CH4)offers a sustainable pathway towards a carbon energy cycle.However,the photocatalytic efficiency and selectivity are still unsatisfactory due to the limited availability of active sites on the current photocatalysts.To resolve this issue,the design of oxygen vacancies(OVs)in metal-oxide semiconductors is an effective option.Herein,in situ deposition of TiO_(2) onto SiO_(2) nanospheres to construct a SiO_(2)@TiO_(2) core-shell structure was performed to modulate the oxygen vacancy concentrations.Meanwhile,charge redistribution led to the formation of abundant OV-regulated Ti-Ti(Ti-OV-Ti)dual sites.It is revealed that Ti-OV-Ti dual sites served as the key active site for capturing the photogenerated electrons during light-driven CO_(2) reduction reaction(CO_(2)RR).Such electron-rich active sites enabled efficient CO_(2) adsorption and activation,thus lowering the energy barrier associated with the rate-determining step.More importantly,the formation of a highly stable*CHO intermediate at Ti-OV-Ti dual sites energetically favored the reaction pathway towards the production of CH4 rather than CO,thereby facilitating the selective product of CH_(4).As a result,SiO_(2)@TiO_(2)-50 with an optimized oxygen vacancy concentration of 9.0% showed a remarkable selectivity(90.32%)for CH_(4) production with a rate of 13.21μmol g^(-1) h^(-1),which is 17.38-fold higher than that of pristine TiO_(2).This study provides a new avenue for engineering superior photocatalysts through a rational methodology towards selective reduction of CO_(2).展开更多
In this manuscript we present a nonlinear site amplification model for ground-motion prediction equations(GMPEs)in Japan,using a site period-based site class and a site impedance ratio as site parameters.We used a lar...In this manuscript we present a nonlinear site amplification model for ground-motion prediction equations(GMPEs)in Japan,using a site period-based site class and a site impedance ratio as site parameters.We used a large number of shear-wave velocity profiles from the Kiban-Kyoshin network(KiK-net)and the Kyoshin network(K-NET)to construct the one-dimensional(1D)numerical models.The strong-motion records from rock-sites in Japan with different earthquake categories and taken from the Pacific Earthquake Engineering Research Center dataset were used in this study.We fit a set of 1D site amplification models using the spectral amplification ratios derived from 1D equivalent linear analyses.Parameters of site impedance ratios for both linear and nonlinear site response were included in the 1D model.The 1D model could be implemented into GMPEs using a new proposed adjustment method.The adjusted site amplification ratios retain the nonlinear characteristics of the 1D model for strong motions and match the linear amplification ratio in GMPE for weak motions.The nonlinearity of the present site model is reasonably similar to that of the historical models,and the present site model could satisfactorily capture the nonlinear site response in empirical data.展开更多
It is very appealing that 5-hydroxymethylfurfural(HMF)is electrocatalytical oxidized as 2,5-furandicarboxylic acid(FDCA)linking to non-classical cathodic hydrogen(H_(2))production.However,the electrocatalysts for elec...It is very appealing that 5-hydroxymethylfurfural(HMF)is electrocatalytical oxidized as 2,5-furandicarboxylic acid(FDCA)linking to non-classical cathodic hydrogen(H_(2))production.However,the electrocatalysts for electrocatalytic HMF oxidative reaction(e-HMFOR)have been facing low Faradaic efficiency(FE)and high water splitting voltage.Herein,we propose a strategy of the NiSeO_(3)@(CoSeO_(3))_(4)heterojunction by constructing a Co-Ni paired site,where the Co site is in charge of adsorbing for HMF while the electrons are transferred to the Ni site,thus giving the NiSeO_(3)@(CoSeO_(3))_(4)heterojunction superior electrocata lytic performances for e-HMFOR and water splitting.By optimizing conditions,the NiSeO_(3)@(CoSeO_(3))_(4)heterojunction has high conversion of 99.7%,high selectivity of 99.9%,and high FE of 98.4%at 1.3 V,as well as low cell voltage of 1.31 V at 10 mA cm^(-2)in 1 M KOH+0.1 M HMF.This study offers a potential insight for e-HMFOR to high value-added FDCA coupling water splitting to produce H_(2)in an economical manner.展开更多
Gallium nitride(GaN)single crystal with prominent electron mobility and heat resistance have great potential in the high temperature integrate electric power systems.However,the sluggish charge storage kinetics and in...Gallium nitride(GaN)single crystal with prominent electron mobility and heat resistance have great potential in the high temperature integrate electric power systems.However,the sluggish charge storage kinetics and inadequate energy densities are bottlenecks to its practical application.Herein,the self-supported GaN/Mn_(3)O_(4) integrated electrode is developed for both energy harvesting and storage under the high temperature environment.The experimental and theoretical calculations results reveal that such integrated structures with Mn-N heterointerface bring abundant active sites and reconstruct low-energy barrier channels for efficient charge transferring,reasonably optimizing the ions adsorption ability and strengthening the structural stability.Consequently,the assembled GaN based supercapacitors deliver the power density of 34.0 mW cm^(-2) with capacitance retention of 81.3%after 10000 cycles at 130℃.This work innovatively correlates the centimeter scale GaN single crystal with ideal theoretical capacity Mn_(3)O_(4) and provides an effective avenue for the follow-up energy storage applications of the wide bandgap semiconductor.展开更多
The CO_(2)-assisted oxidative dehydrogenation of ethane(CO_(2)-ODHE)provides a promising way to produce ethylene and utilize CO_(2).Simultaneous upgrading of ethane into the high value-added chemical products and the ...The CO_(2)-assisted oxidative dehydrogenation of ethane(CO_(2)-ODHE)provides a promising way to produce ethylene and utilize CO_(2).Simultaneous upgrading of ethane into the high value-added chemical products and the reduction of greenhouse gas CO_(2)emissions could be achieved.However,the targeted breaking of the C-C/C-H bonds of ethane is still a challenge for the designed catalysts.In this paper,ZnO-doped ZrO_(2)bifunctional catalysts(Zn_(x)ZrO)with different Zn/Zr molar ratios were prepared by the deposition-precipitation method,and the functions of various sites for CO_(2)-ODHE reaction were revealed by in situ characterizations and ethane pulse experiment:the medium-strength acidic Zn-O-Zr sites are responsible for the purposefully cracking of ethane C-H bonds to ethylene,while the more oxygen vacancies(OV)created by the introduction of Zn^(2+)are responsible for the efficient activation C=O bonds of CO_(2),thus promoting the RWGS reaction.In addition,the Zn0.2ZrO catalyst demonstrated excellent catalytic performances,with C_(2)H_(6)conversion,C_(2)H_(4)yield,and CO_(2)conversion about 19.1%,10.5%,and 10.6%within 5 h,respectively(600℃,GHSV=3000 mL/(g·h)).Especially,the initial ethylene space-time yield of 355.5μmol/(min·g)was obtained under 6000 mL/(g·h);Finally,the tandem reaction mechanism of ethane dehydrogenation and RWGS was revealed.展开更多
Electrocatalytic conversion of renewable biomass is emerging as a promising route for sustainable chemical production;hence it urgently calls for developing efficient electrocatalysts with low potentials and high curr...Electrocatalytic conversion of renewable biomass is emerging as a promising route for sustainable chemical production;hence it urgently calls for developing efficient electrocatalysts with low potentials and high current densities.Herein,a Pr-doped Co(OH)_(2)hexagonal sheet(Pr/Co=1/9,in mole)is synthesized by electrodeposition as highly performant catalyst for 5-hydroxymethylfurfural(HMF)oxidation reaction(HMFOR)to produce 2,5-furandicarboxylic acid(FDCA).This novel and low-cost catalyst possesses a rather low onset potential of 1.05 V(vs.RHE)and requires only 1.10 V(vs.RHE)to reach a current density of 10 mA cm^(-2)for HMFOR,significantly outperforming Co(OH)_(2)benchmark(i.e.,210 mV higher to reach10 m A cm^(-2)).The origin of Pr promotion effect as well as the evolution of CoOOH catalytic sites and HMFOR process has been deeply elucidated by physical characterizations,kinetic experiments,in situ electrochemical techniques,and theoretical calculations.The unique Pr-ameliorated CoOOH active centers enable 100%conversion of HMF,99.6%selectivity of FDCA,and 99.7%Faraday efficiency,with a superior cycling durability toward HMFOR.This can be one of the most outstanding results for Co-based HMFOR catalysts to date in the literature.Thereby this work can help open up new horizons for constructing novel and efficient Co-based electrocatalysts by the utilization of lanthanide elements.展开更多
Antimony smelting activities damage the soil and vegetation surroundings while generating economic value.However,no standardizedmethods are available to diagnose the extent of soil degradation at antimony smelting sit...Antimony smelting activities damage the soil and vegetation surroundings while generating economic value.However,no standardizedmethods are available to diagnose the extent of soil degradation at antimony smelting sites.This study developed a standardized framework for assessing soil quality by consideringmicrobial-induced resilience and heavymetal contamination at Xikuangshan antimony smelting site.The soil resilience index(SRI)and soil contamination index(SCI)were calculated byMinimum Data Set and geo-accumulation model,respectively.After standardized by a multi-criteria quantitative procedure of modified Nemerow’s pollution index(NPI),the integrated assessment of soil quality index(SQI),which is the minimumof SRINPI and SCINPI,was achieved.The results showed that Sb and As were the prominent metal(loid)pollutants,and significant correlations between SQI and SRI indicated that the poor soil quality was mainly caused by the low level of soil resilience.The primary limiting factors of SRI were Fungi in high andmiddle contaminated areas,and Skermanella in low contaminated area,suggesting that the weak soil resilience was caused by low specific microbial abundances.Microbial regulation and phytoremediation are greatly required to improve the soil quality at antimony smelting sites from the perspectives of pollution control and resilience improvement.This study improves our understanding of ecological effects of antimony smelting sites and provides a theoretical basis for ecological restoration and sustainable development of mining areas.展开更多
Herein,a new type of two-dimensional(2D)/2D Ti_(3)C_(2)/TiO_(2) heterojunction was developed for efficient photocatalytic nitrogen reduction reaction(NRR),in which TiO_(2) nanosheets(TiO_(2) Ns)were designed as the ma...Herein,a new type of two-dimensional(2D)/2D Ti_(3)C_(2)/TiO_(2) heterojunction was developed for efficient photocatalytic nitrogen reduction reaction(NRR),in which TiO_(2) nanosheets(TiO_(2) Ns)were designed as the main catalyst,while Ti_(3)C_(2) MXene served as the co-catalyst.Experimental and theoretical results revealed that Ti_(3)C_(2) MXene introduced electron-rich unsaturated Ti sites,serving as highly active sites for both the adsorption and activation of N_(2) on the Ti_(3)C_(2)/TiO_(2) heterojunction.Furthermore,the 2D/2D Ti_(3)C_(2)/TiO_(2) heterostructure greatly promoted the directional separation and transfer of charge carriers,facilitated by the internal electric field.This structural feature enabled the spatial separation of the N_(2) reduction and H2 O oxidation half-reactions on the distinct surfaces of Ti_(3)C_(2)(001)and TiO_(2)(001),con-sequently reducing the reaction energy barrier for each respective process.The synergistic effects arising from the interface and surface interactions within the heterojunction conspicuously improved the photo-catalytic NRR activity.As a result,the optimized Ti_(3)C_(2)/TiO_(2) heterojunction exhibited a high NH_(3) produc-tion rate of 24.4μmol g−1 h−1 in the absence of sacrificial agents,representing a remarkable 12.8-fold increase compared to individual TiO_(2) Ns.This work provides new insights into rational design of high-performance heterogeneous photocatalysts and offers a deeper understanding of the mechanism under-lying surface active sites in the photocatalytic NRR process.展开更多
In recent years,numer-ous single-atom catalysts(SACs)have been synthesized to activate persulfate(PS)by a non-radical pathway because of its high se-lectivity,and activity for the cata-lyst.Metal-nitrogen-carbon(M-N_(...In recent years,numer-ous single-atom catalysts(SACs)have been synthesized to activate persulfate(PS)by a non-radical pathway because of its high se-lectivity,and activity for the cata-lyst.Metal-nitrogen-carbon(M-N_(x)-C)has been identified as the key active site in SACs.Although methods for preparing SACs have been extensively reported,a systematic summary of the direct construction of M-N_(x)-C,espe-cially unconventional metal-nitrogen-carbon(UM-N_(x)-C,x≠4),on SACs for PS non-radical activation has still not been reported.The role of the M-N_(x)-C active sites on PS non-radical activation is discussed and methods for the formation of M-N_(x)-C and UM-N_(x)-C active sites in SACs and the effect of catalyst carriers such as carbon nitride(g-C_(3)N_(4)),MOFs,COFs,and other car-bon materials are reviewed.Direct and indirect methods,especially for UM-N_(x)-C active site formation,are also elaborated.Factors affecting the formation of a M-N_(x)-C active site on SACs are also discussed.Prospects for the use of M-N_(x)-C active sites for the non-radical activation of PS by SACs to remove organic contaminants from wastewater are evaluated.展开更多
Objective N6-methyladenosine(m6A),the most prevalent epigenetic modification in eukaryotic RNA,plays a pivotal role in regulating cellular differentiation and developmental processes,with its dysregulation implicated ...Objective N6-methyladenosine(m6A),the most prevalent epigenetic modification in eukaryotic RNA,plays a pivotal role in regulating cellular differentiation and developmental processes,with its dysregulation implicated in diverse pathological conditions.Accurate prediction of m6A sites is critical for elucidating their regulatory mechanisms and informing drug development.However,traditional experimental methods are time-consuming and costly.Although various computational approaches have been proposed,challenges remain in feature learning,predictive accuracy,and generalization.Here,we present m6A-PSRA,a dual-branch residual-network-based predictor that fully exploits RNA sequence information to enhance prediction performance and model generalization.Methods m6A-PSRA adopts a parallel dual-branch network architecture to comprehensively extract RNA sequence features via two independent pathways.The first branch applies one-hot encoding to transform the RNA sequence into a numerical matrix while strictly preserving positional information and sequence continuity.This ensures that the biological context conveyed by nucleotide order is retained.A bidirectional long short-term memory network(BiLSTM)then processes the encoded matrix,capturing both forward and backward dependencies between bases to resolve contextual correlations.The second branch employs a k-mer tokenization strategy(k=3),decomposing the sequence into overlapping 3-mer subsequences to capture local sequence patterns.A pre-trained Doc2vec model maps these subsequences into fixeddimensional vectors,reducing feature dimensionality while extracting latent global semantic information via context learning.Both branches integrate residual networks(ResNet)and a self-attention mechanism:ResNet mitigates vanishing gradients through skip connections,preserving feature integrity,while self-attention adaptively assigns weights to focus on sequence regions most relevant to methylation prediction.This synergy enhances both feature learning and generalization capability.Results Across 11 tissues from humans,mice,and rats,m6A-PSRA consistently outperformed existing methods in accuracy(ACC)and area under the curve(AUC),achieving>90%ACC and>95%AUC in every tissue tested,indicating strong cross-species and cross-tissue adaptability.Validation on independent datasets—including three human cell lines(MOLM1,HEK293,A549)and a long-sequence dataset(m6A_IND,1001 nt)—confirmed stable performance across varied biological contexts and sequence lengths.Ablation studies demonstrated that the dual-branch architecture,residual network,and self-attention mechanism each contribute critically to performance,with their combination reducing interference between pathways.Motif analysis revealed an enrichment of m6A sites in guanine(G)and cytosine(C),consistent with known regulatory patterns,supporting the model’s biological plausibility.Conclusion m6A-PSRA effectively captures RNA sequence features,achieving high prediction accuracy and robust generalization across tissues and species,providing an efficient computational tool for m6A methylation site prediction.展开更多
基金the financial support from the National Natural Science Foundation of China(52172110,52472231,52311530113)Shanghai"Science and Technology Innovation Action Plan"intergovernmental international science and technology cooperation project(23520710600)+1 种基金Science and Technology Commission of Shanghai Municipality(22DZ1205600)the Central Guidance on Science and Technology Development Fund of Zhejiang Province(2024ZY01011)。
文摘Investigating structural and hydroxyl group effects in electrooxidation of alcohols to value-added products by solid-acid electrocatalysts is essential for upgrading biomass alcohols.Herein,we report efficient electrocatalytic oxidations of saturated alcohols(C_(1)-C_(6))to selectively form formate using Ni Co hydroxide(Ni Co-OH)derived Ni Co_(2)O_(4)solid-acid electrocatalysts with balanced Lewis acid(LASs)and Brønsted acid sites(BASs).Thermal treatment transforms BASs-rich(89.6%)Ni Co-OH into Ni Co_(2)O_(4)with nearly equal distribution of LASs(53.1%)and BASs(46.9%)which synergistically promote adsorption and activation of OH-and alcohol molecules for enhanced oxidation activity.In contrast,BASs-enriched Ni Co-OH facilitates formation of higher valence metal sites,beneficial for water oxidation.The combined experimental studies and theoretical calculation imply the oxidation ability of C1-C6alcohols increases as increased number of hydroxyl groups and decreased HOMO-LUMO gaps:methanol(C_(1))<ethylene glycol(C_(2))<glycerol(C3)<meso-erythritol(C4)<xylitol(C5)<sorbitol(C6),while the formate selectivity shows the opposite trend from 100 to 80%.This study unveils synergistic roles of LASs and BASs,as well as hydroxyl group effect in electro-upgrading of alcohols using solid-acid electrocatalysts.
基金supported by the National Natural Science Foundation of China(No.51878292).
文摘Large-scale CO_(2)emissions have exacerbated the greenhouse effect,reinforcing the critical need for efficient CO_(2)mitigation methods.Plasma-catalytic technology enables CO_(2)conversion under mild conditions,especially for CO_(2)methanation(the Sabatier reaction),which has attracted significant attention due to its economic benefits and the potential for safe energy transportation via existing natural gas pipelines.The development of high-performance CO_(2)methanation catalysts remains an ongoing and long-term objective,and there is a lack of adequate in-situ characterization techniques to investigate the mechanisms.This study focuses on the Ni/La_(2)O_(3)(LN)catalyst and introduces two CO_(2)activation strategies through F and Na modifications:the Ni-Ov-Ni site activation with electron transfer from Ni0 under low-power conditions and basic site activation under high-power conditions.The LN-NaF catalysts enhance CO_(2)methanation activity across the entire power range compared to LN,achieving a CO_(2)conversion of 86.3%and CH4 selectivity of 99.4%.Additionally,LN-F(h)reaches a CH4 yield 4.15 times higher than that of LN at low power.Furthermore,in-situ diffuse reflectance infrared Fourier transform(DRIFT)spectroscopy with a self-made reactor are performed under plasma-catalytic conditions to reveal the CO_(2)adsorption and conversion mechanisms,indicating that different dopants(F,Na,and NaF)exhibit promoting effects on different intermediates,resulting in variations in CO_(2)methanation activity.This study provides valuable insights for improving catalyst performance and a thorough comprehension of mechanisms in CO_(2)methanation.
基金supported by the National Natural Science Foundation of China(Nos.W2412093 and 52170068)the Fundamental Research Funds for the Central Universities(No.DUT24RC(3)079).
文摘Peroxymonosulfate(PMS)-based advanced oxidation technology has been proven to be a viable option for the decontamination of organic pollutants from water bodies.Advanced catalyst design is essential to this technology.Herein,a vanadium-doped LaFeO_(3) perovskite(LFO-V)featuring asymmetric Fe-O-V sites was rationally designed.Thanks to orbital electron interaction between Fe and V atoms,the modified electronic structure elevated electron density near the Fermi energy level while reducing the energy barrier toward effective PMS activation.This facilitated concurrent PMS reduction at the Fe sites to generate SO_(4)^(·-)and·OH(57.7%),and PMS oxidation at V sites to produce ^(1)O_(2)(42.3%).The LFO-V/PMS system demonstrated excellent tetracycline(TC)degradation performance with a 2-fold enhancement in rate constant compared to that of pristine LFO.Further,the LFO-V maintained long-term stability,and the toxicity of degradation intermediates was evaluated through microbial metabolomics.This work establishes an effective route to regulate the PMS activation pathways through precise electronic structure modulation,advancing the rational design of advanced Fenton-like catalysts.
基金supported by the Science and Technology Research and Development Program Project of China Railway Group Limited (Grant No.2022-Major-17)the National Natural Science Foundation of China (Grant Nos.52578619,52178180)+2 种基金the National Key Research and Development Program of China (Grant No.2022YFC3004304)the Frontier Cross Research Project of Central South University (Grant No.2023QYJC006)the Natural Science Foundation of Hunan Province Funding Project (Grant No.2023JJ40724)。
文摘Under earthquake action, different site conditions have a notable impact on the dynamic response of high-speed railway bridges after earthquakes, which in turn poses a threat to the running stability of trains in the post-earthquake period. Therefore, establishing a calculation method for the post-earthquake train speed threshold that considers the influence of different site characteristics is of great engineering significance. Taking the CRTS Ⅲ slab track as the research object, this study is based on the track irregularity root mean square rate(TRR), which the authors proposed earlier to quantify the track regularity level. Using the nonlinear least squares fitting method, the mapping relationship between the TRR and the postearthquake train running performance indicators on bridges is established. Furthermore, the influence of laws governing site categories and train speeds on post-earthquake train running performance on bridges is analyzed, and a train speed threshold for bridges based on running performance under random site conditions is proposed. The research results indicate that all train running performance indicators increase significantly with the increase of train operating speed;different site categories have a significant impact on post-earthquake track residual deformation and train running stability. The greater the amplitude of postearthquake track alignment residual deformation, the lower the threshold for the stable running speed of trains after the earthquake, with the speed threshold decreasing by up to 20%. The research outcomes can provide technical references for the post-earthquake safe operation and maintenance of high-speed railway bridges under complex site conditions, as well as the formulation of targeted train speed control schemes.
基金supported byHainan Provincial Natural Science Foundation of China(Nos.422RC600,519QN175)National Natural Science Foundation ofChina(Nos.52160018,21801053,52400206,52500209)High-Level Talent Program of Hainan Province(Nos.XJ2400008202,XJ2400011473).
文摘Oxidative magnetization has attracted great attention as an efficient strategy for modulating physiochemical properties of magnetic biochar.In this paper,a K_(2)FeO_(4)-involving hydrothermal oxidative magnetization was explored to regulate multiple micro-structures for manufacture magnetic hydrochar(MHC)for Fenton-like degradation of tetracycline in aqueous solution.Diverse shapes of Fe_(3)O_(4) and nano zero-valent iron(nZVI)were doped with abundant oxygen containing groups and persistent free radicals(PFRs).Multiple catalysis sites including iron species,PFRs,oxygen containing groups,and graphite defects contributed to accelerate the Fenton-like degradation with synergistic effect.Notably,MHC achieved a tetracycline removal rate of 99% within 60 min at 50 mg/L,with a total organic carbon(TOC)removal rate of 35%.Furthermore,after four cycles of reuse,the degradation efficiency slightly decreased to 93%.This study highlights the potential of magnetic hydrochar with multiple catalytic sites in the effective and sustainable degradation of pollutants.
基金partially supported by the National Natural Science Foundation of China(Nos.22373092,22288201)CAS Project for Young Scientists in Basic Research(YSBR-051)+1 种基金Innovation Program for Quantum Science and Technology(2021ZD0303306)supported by University of Science and Technology of China Tang Scholarship and State Scholarship Fund(202206345005)。
文摘Single atom catalysts supported by two-dimensional(2D)materials,including graphene,g-C_(3)N_(4),and graphdiyne,ex-hibit promising electrocatalytic nitrogen reduction reaction(NRR)activity.Nevertheless,sometimes theoretical works failed to predict the high activity of NRR of single atom cat-alysts,especially for Fe,Co,Mn,Cu,Ru.In this work,based on DFT calculations,it is suggested that dual-atom sites on N doped graphene(M_(2)@N-graphene)rather than single-atom sites are more likely to be the active sites for NRR.Notably,Fe_(2)@N_(3),Co_(2)@N_(2),Mn_(2)@N_(2),Cu_(2)@N_(1),and Ru_(2)@N_(3)endow the best catalytic activity with corresponding limiting potentials of-0.26,-0.18,-0.17,-0.39,and-0.30 V,re-spectively.Furthermore,on g-C_(3)N_(4)and graphdiyne,triple-atom sites(TAS,M_(3))such as Ru_(3)(Co_(3))@g-C_(3)N_(4)and Ru_(3)(Rh_(3))@graphdiyne are expected to exhibit higher stability and NRR catalytic performance than single-atom sites(SAS)and dual-atom sites(DAS),with corresponding limiting potentials of-0.28,-0.48,-0.24,and-0.23 V.The calculated results with the corresponding experimental potentials indicate that the origin of superior NRR ac-tivity observed in experiments may be contributed by M_(2)or M_(3)on 2D materials.This study provides an in-depth investigation into real active NRR sites of metal atoms supported on 2D materials and contributes to the design of effective NRR catalysts.
文摘Molecular recognition of bioreceptors and enzymes relies on orthogonal interactions with small molecules within their cavity. To date, Chinese scientists have developed three types of strategies for introducing active sites inside the cavity of macrocyclic arenes to better mimic molecular recognition of bioreceptors and enzymes.The editorial aims to enlighten scientists in this field when they develop novel macrocycles for molecular recognition, supramolecular assembly, and applications.
基金supported by the research project of code PID2020-112839RB-I00 funded by the Spanish State Research Agency(AEI)of the Ministry of Science and Innovation(MCIN/AEI/10.13039/501100011033)in receipt of a Severo Ochoa Fellowship from the Asturias Government(code BP21-125).
文摘This research aimed to obtain accurate estimates of the productivity of eucalyptus plantations under different climate change scenarios without the need for additional fieldwork.Thus,we used tree growth data from 1,102research plots,existing spatially continuous environmental data,and the random forest(RF) algorithm to construct raster-based models.We constructed models to predict site index(SI) at landscape scale(250m·pixel^(-1)),which is useful for planning purposes and for analyzing the effect of climate change on productivity,and at forest plot scale(resolutions of 10,25,50,and 100 m-pixel^(-1)),which is essential for predicting plantation yields.All models explained~50% of site index variability,as is usual in this type of study.We found that the different spatial resolutions of predictor variables did not affect the amount of variability explained.This finding may be due to two opposing effects on the explained variability at finer scales:a positive effect,as finer scales enable capture of microscale landform variability through a high-resolution digital elevation model(DEM),and a negative effect due to the introduction of "noise" when downscaling the climatic and lithological information from coarser scales.Elevation and the climatic variables(mainly temperature) were the most important predictor variables:For every 100 m-increase in elevation,the productivity decreased by on average 0.3-0.9 m of site index(1-1.3 m^(3)·ha^(-1)·year^(-1) of maximum mean annual increment in volume) and for each degree-Celsiusincrease in annual mean temperature,productivity increased by about 2.2 m in site index(3 m^(3)·ha^(-1)·year^(-1)of maximum mean annual increment in volume).Due to the forecasted increase in temperatures under climate change,productivity is expected to increase significantly in Eucalyptus globulus plantations in northern Spain in the coming decades,by between 1.68% and 3.38% of the current average site index under the most pessimistic climate change scenario and between 1.79% and 2.48% of the current average site index for the moderate scenario.We conclude that currently available spatially continuous environmental data can be used to develop accurate raster data models for predicting site productivity for E.globulus without the need for fieldwork.The spatially explicit maps produced in the study provide support to forest planners,forest managers,private landowners and politicians,enabling well-founded decisions to be made regarding selection of the best sites for afforestation and providing accurate yield predictions for the plantations.
基金support of the National Natu-ral Science Foundation of China(No.62004143,22476058,and 22076052)the Key R&D Program of Hubei Province(No.2022BAA084).
文摘Cu metal and its oxides have attracted much attention for photocatalytic CO_(2)reduction reaction(CO_(2)RR),but the stability and effects of Cu oxidation states on CO_(2)RR are not fully understood.Cu^(x+)/Cu^(0)-loaded graphitic carbon nitride(g-C_(3)N_(4))heterojunctions(Cu-CuO_(x)/g-C_(3)N_(4))are fabricated via a stepwise calcination method for efficient photocatalytic CO_(2)RR.Cu_(2)O is the main component of Cu-CuO_(x)and the mixed valence Cu includes Cu^(0),Cu^(+),and Cu^(2+),which play the role of charge trapping sites and redox catalytic centers during the photocatalytic CO_(2)RR process.The main products were CO and CH_(4)for the CO_(2)RR with production rates of 14.45 and 0.66μmol g^(-1)h^(-1)for CO and CH_(4),which were higher than those for g-C_(3)N_(4)and Cu-CuO_(x),respectively.This photocatalytic CO_(2)RR performance is attributed to the ultrafast switching of“Cu^(x+)−Cu^(0)”and e_(CB^(−))/h_(VB^(+))trapping transformation in Cu-CuO_(x)benefited from the built-in IEF between Cu-CuO_(x)and g-C_(3)N_(4),increasing the efficient photogenerated e_(CB^(−)),and enabling the stability of Cu-CuO_(x)/g-C_(3)N_(4).Cu^(x+)adsorbed by H_(2)O works as the electron trapping site to change to Cu^(0)and switch to the hole trapping site;Cu^(0)works as the hole trapping site to change to Cu^(x+)and switch to the electron trapping site,causing the CO_(2)RR of the adsorbed CO_(2).Moreover,the coordinated Cu^(0)and Cu^(+)species facilitate the activation of the adsorbed CO_(2)and^(∗)CO generation,these adsorbed^(∗)CO on Cu^(0)and Cu^(+)detected by in-situ DRIFTS quickly transformed to^(∗)CHO with a lower energy barrier benefited from the mixed Cu^(0)/Cu^(+)active sites during CORR to produce CH_(4).This finding provides a new insight into the influence of mixed valence Cu during photocatalytic CO_(2)RR.
基金supported by the National Natural Science Foundation of China(No.21773089,22202037)the Science and Technology Development Plan Project of Jilin Province,China(No.20240101192JC)the Fundamental Research Funds for the Central Universities(No.2412023QD019).
文摘Controlled photocatalytic conversion of CO_(2) into premium fuel such as methane(CH4)offers a sustainable pathway towards a carbon energy cycle.However,the photocatalytic efficiency and selectivity are still unsatisfactory due to the limited availability of active sites on the current photocatalysts.To resolve this issue,the design of oxygen vacancies(OVs)in metal-oxide semiconductors is an effective option.Herein,in situ deposition of TiO_(2) onto SiO_(2) nanospheres to construct a SiO_(2)@TiO_(2) core-shell structure was performed to modulate the oxygen vacancy concentrations.Meanwhile,charge redistribution led to the formation of abundant OV-regulated Ti-Ti(Ti-OV-Ti)dual sites.It is revealed that Ti-OV-Ti dual sites served as the key active site for capturing the photogenerated electrons during light-driven CO_(2) reduction reaction(CO_(2)RR).Such electron-rich active sites enabled efficient CO_(2) adsorption and activation,thus lowering the energy barrier associated with the rate-determining step.More importantly,the formation of a highly stable*CHO intermediate at Ti-OV-Ti dual sites energetically favored the reaction pathway towards the production of CH4 rather than CO,thereby facilitating the selective product of CH_(4).As a result,SiO_(2)@TiO_(2)-50 with an optimized oxygen vacancy concentration of 9.0% showed a remarkable selectivity(90.32%)for CH_(4) production with a rate of 13.21μmol g^(-1) h^(-1),which is 17.38-fold higher than that of pristine TiO_(2).This study provides a new avenue for engineering superior photocatalysts through a rational methodology towards selective reduction of CO_(2).
基金National Science Foundation of China under Grant No.51578470。
文摘In this manuscript we present a nonlinear site amplification model for ground-motion prediction equations(GMPEs)in Japan,using a site period-based site class and a site impedance ratio as site parameters.We used a large number of shear-wave velocity profiles from the Kiban-Kyoshin network(KiK-net)and the Kyoshin network(K-NET)to construct the one-dimensional(1D)numerical models.The strong-motion records from rock-sites in Japan with different earthquake categories and taken from the Pacific Earthquake Engineering Research Center dataset were used in this study.We fit a set of 1D site amplification models using the spectral amplification ratios derived from 1D equivalent linear analyses.Parameters of site impedance ratios for both linear and nonlinear site response were included in the 1D model.The 1D model could be implemented into GMPEs using a new proposed adjustment method.The adjusted site amplification ratios retain the nonlinear characteristics of the 1D model for strong motions and match the linear amplification ratio in GMPE for weak motions.The nonlinearity of the present site model is reasonably similar to that of the historical models,and the present site model could satisfactorily capture the nonlinear site response in empirical data.
基金supported by the National Natural Science Foundation of China(22302019)the Changzhou Sci&Tech Program(CJ20220214).
文摘It is very appealing that 5-hydroxymethylfurfural(HMF)is electrocatalytical oxidized as 2,5-furandicarboxylic acid(FDCA)linking to non-classical cathodic hydrogen(H_(2))production.However,the electrocatalysts for electrocatalytic HMF oxidative reaction(e-HMFOR)have been facing low Faradaic efficiency(FE)and high water splitting voltage.Herein,we propose a strategy of the NiSeO_(3)@(CoSeO_(3))_(4)heterojunction by constructing a Co-Ni paired site,where the Co site is in charge of adsorbing for HMF while the electrons are transferred to the Ni site,thus giving the NiSeO_(3)@(CoSeO_(3))_(4)heterojunction superior electrocata lytic performances for e-HMFOR and water splitting.By optimizing conditions,the NiSeO_(3)@(CoSeO_(3))_(4)heterojunction has high conversion of 99.7%,high selectivity of 99.9%,and high FE of 98.4%at 1.3 V,as well as low cell voltage of 1.31 V at 10 mA cm^(-2)in 1 M KOH+0.1 M HMF.This study offers a potential insight for e-HMFOR to high value-added FDCA coupling water splitting to produce H_(2)in an economical manner.
基金supported by NSFC(Grant No.52202265,52302004,52472010,62434010)the Taishan Scholars Program of Shandong Province(tsqn202306330)+1 种基金Shenzhen Science and Technology Program(JCYJ20230807094009018)Xiaomi Young Talents Program(2023XM06).
文摘Gallium nitride(GaN)single crystal with prominent electron mobility and heat resistance have great potential in the high temperature integrate electric power systems.However,the sluggish charge storage kinetics and inadequate energy densities are bottlenecks to its practical application.Herein,the self-supported GaN/Mn_(3)O_(4) integrated electrode is developed for both energy harvesting and storage under the high temperature environment.The experimental and theoretical calculations results reveal that such integrated structures with Mn-N heterointerface bring abundant active sites and reconstruct low-energy barrier channels for efficient charge transferring,reasonably optimizing the ions adsorption ability and strengthening the structural stability.Consequently,the assembled GaN based supercapacitors deliver the power density of 34.0 mW cm^(-2) with capacitance retention of 81.3%after 10000 cycles at 130℃.This work innovatively correlates the centimeter scale GaN single crystal with ideal theoretical capacity Mn_(3)O_(4) and provides an effective avenue for the follow-up energy storage applications of the wide bandgap semiconductor.
文摘The CO_(2)-assisted oxidative dehydrogenation of ethane(CO_(2)-ODHE)provides a promising way to produce ethylene and utilize CO_(2).Simultaneous upgrading of ethane into the high value-added chemical products and the reduction of greenhouse gas CO_(2)emissions could be achieved.However,the targeted breaking of the C-C/C-H bonds of ethane is still a challenge for the designed catalysts.In this paper,ZnO-doped ZrO_(2)bifunctional catalysts(Zn_(x)ZrO)with different Zn/Zr molar ratios were prepared by the deposition-precipitation method,and the functions of various sites for CO_(2)-ODHE reaction were revealed by in situ characterizations and ethane pulse experiment:the medium-strength acidic Zn-O-Zr sites are responsible for the purposefully cracking of ethane C-H bonds to ethylene,while the more oxygen vacancies(OV)created by the introduction of Zn^(2+)are responsible for the efficient activation C=O bonds of CO_(2),thus promoting the RWGS reaction.In addition,the Zn0.2ZrO catalyst demonstrated excellent catalytic performances,with C_(2)H_(6)conversion,C_(2)H_(4)yield,and CO_(2)conversion about 19.1%,10.5%,and 10.6%within 5 h,respectively(600℃,GHSV=3000 mL/(g·h)).Especially,the initial ethylene space-time yield of 355.5μmol/(min·g)was obtained under 6000 mL/(g·h);Finally,the tandem reaction mechanism of ethane dehydrogenation and RWGS was revealed.
基金National Natural Science Foundation of China(No.22272149,22062025)Yunnan University’s Research Innovation Fund for Graduate Students(No.KC-23234085)+1 种基金Workstation of Academician Chen Jing of Yunnan Province(No.202105AF150012)Free Exploration Fund for Academician(No.202405AA350001)。
文摘Electrocatalytic conversion of renewable biomass is emerging as a promising route for sustainable chemical production;hence it urgently calls for developing efficient electrocatalysts with low potentials and high current densities.Herein,a Pr-doped Co(OH)_(2)hexagonal sheet(Pr/Co=1/9,in mole)is synthesized by electrodeposition as highly performant catalyst for 5-hydroxymethylfurfural(HMF)oxidation reaction(HMFOR)to produce 2,5-furandicarboxylic acid(FDCA).This novel and low-cost catalyst possesses a rather low onset potential of 1.05 V(vs.RHE)and requires only 1.10 V(vs.RHE)to reach a current density of 10 mA cm^(-2)for HMFOR,significantly outperforming Co(OH)_(2)benchmark(i.e.,210 mV higher to reach10 m A cm^(-2)).The origin of Pr promotion effect as well as the evolution of CoOOH catalytic sites and HMFOR process has been deeply elucidated by physical characterizations,kinetic experiments,in situ electrochemical techniques,and theoretical calculations.The unique Pr-ameliorated CoOOH active centers enable 100%conversion of HMF,99.6%selectivity of FDCA,and 99.7%Faraday efficiency,with a superior cycling durability toward HMFOR.This can be one of the most outstanding results for Co-based HMFOR catalysts to date in the literature.Thereby this work can help open up new horizons for constructing novel and efficient Co-based electrocatalysts by the utilization of lanthanide elements.
基金supported by the National Key Research and Development Program of China (No.2019YFC1803604)the National Natural Science Foundation of China (Nos.42007306 and 42277193).
文摘Antimony smelting activities damage the soil and vegetation surroundings while generating economic value.However,no standardizedmethods are available to diagnose the extent of soil degradation at antimony smelting sites.This study developed a standardized framework for assessing soil quality by consideringmicrobial-induced resilience and heavymetal contamination at Xikuangshan antimony smelting site.The soil resilience index(SRI)and soil contamination index(SCI)were calculated byMinimum Data Set and geo-accumulation model,respectively.After standardized by a multi-criteria quantitative procedure of modified Nemerow’s pollution index(NPI),the integrated assessment of soil quality index(SQI),which is the minimumof SRINPI and SCINPI,was achieved.The results showed that Sb and As were the prominent metal(loid)pollutants,and significant correlations between SQI and SRI indicated that the poor soil quality was mainly caused by the low level of soil resilience.The primary limiting factors of SRI were Fungi in high andmiddle contaminated areas,and Skermanella in low contaminated area,suggesting that the weak soil resilience was caused by low specific microbial abundances.Microbial regulation and phytoremediation are greatly required to improve the soil quality at antimony smelting sites from the perspectives of pollution control and resilience improvement.This study improves our understanding of ecological effects of antimony smelting sites and provides a theoretical basis for ecological restoration and sustainable development of mining areas.
基金supported by the National Natural Science Foundation of China(No.21773089)the Henan Center for Outstanding Overseas Scientist(No.GZS2024004).
文摘Herein,a new type of two-dimensional(2D)/2D Ti_(3)C_(2)/TiO_(2) heterojunction was developed for efficient photocatalytic nitrogen reduction reaction(NRR),in which TiO_(2) nanosheets(TiO_(2) Ns)were designed as the main catalyst,while Ti_(3)C_(2) MXene served as the co-catalyst.Experimental and theoretical results revealed that Ti_(3)C_(2) MXene introduced electron-rich unsaturated Ti sites,serving as highly active sites for both the adsorption and activation of N_(2) on the Ti_(3)C_(2)/TiO_(2) heterojunction.Furthermore,the 2D/2D Ti_(3)C_(2)/TiO_(2) heterostructure greatly promoted the directional separation and transfer of charge carriers,facilitated by the internal electric field.This structural feature enabled the spatial separation of the N_(2) reduction and H2 O oxidation half-reactions on the distinct surfaces of Ti_(3)C_(2)(001)and TiO_(2)(001),con-sequently reducing the reaction energy barrier for each respective process.The synergistic effects arising from the interface and surface interactions within the heterojunction conspicuously improved the photo-catalytic NRR activity.As a result,the optimized Ti_(3)C_(2)/TiO_(2) heterojunction exhibited a high NH_(3) produc-tion rate of 24.4μmol g−1 h−1 in the absence of sacrificial agents,representing a remarkable 12.8-fold increase compared to individual TiO_(2) Ns.This work provides new insights into rational design of high-performance heterogeneous photocatalysts and offers a deeper understanding of the mechanism under-lying surface active sites in the photocatalytic NRR process.
文摘In recent years,numer-ous single-atom catalysts(SACs)have been synthesized to activate persulfate(PS)by a non-radical pathway because of its high se-lectivity,and activity for the cata-lyst.Metal-nitrogen-carbon(M-N_(x)-C)has been identified as the key active site in SACs.Although methods for preparing SACs have been extensively reported,a systematic summary of the direct construction of M-N_(x)-C,espe-cially unconventional metal-nitrogen-carbon(UM-N_(x)-C,x≠4),on SACs for PS non-radical activation has still not been reported.The role of the M-N_(x)-C active sites on PS non-radical activation is discussed and methods for the formation of M-N_(x)-C and UM-N_(x)-C active sites in SACs and the effect of catalyst carriers such as carbon nitride(g-C_(3)N_(4)),MOFs,COFs,and other car-bon materials are reviewed.Direct and indirect methods,especially for UM-N_(x)-C active site formation,are also elaborated.Factors affecting the formation of a M-N_(x)-C active site on SACs are also discussed.Prospects for the use of M-N_(x)-C active sites for the non-radical activation of PS by SACs to remove organic contaminants from wastewater are evaluated.
基金supported by grants from The National Natural Science Foundation of China(12361104)Yunnan Fundamental Research Projects(202301AT070016,202401AT070036)+2 种基金the Youth Talent Program of Xingdian Talent Support Plan(XDYC-QNRC-2022-0514)the Yunnan Province International Joint Laboratory for Intelligent Integration and Application of Ethnic Multilingualism(202403AP140014)the Open Research Fund of Yunnan Key Laboratory of Statistical Modeling and Data Analysis,Yunnan University(SMDAYB2023004)。
文摘Objective N6-methyladenosine(m6A),the most prevalent epigenetic modification in eukaryotic RNA,plays a pivotal role in regulating cellular differentiation and developmental processes,with its dysregulation implicated in diverse pathological conditions.Accurate prediction of m6A sites is critical for elucidating their regulatory mechanisms and informing drug development.However,traditional experimental methods are time-consuming and costly.Although various computational approaches have been proposed,challenges remain in feature learning,predictive accuracy,and generalization.Here,we present m6A-PSRA,a dual-branch residual-network-based predictor that fully exploits RNA sequence information to enhance prediction performance and model generalization.Methods m6A-PSRA adopts a parallel dual-branch network architecture to comprehensively extract RNA sequence features via two independent pathways.The first branch applies one-hot encoding to transform the RNA sequence into a numerical matrix while strictly preserving positional information and sequence continuity.This ensures that the biological context conveyed by nucleotide order is retained.A bidirectional long short-term memory network(BiLSTM)then processes the encoded matrix,capturing both forward and backward dependencies between bases to resolve contextual correlations.The second branch employs a k-mer tokenization strategy(k=3),decomposing the sequence into overlapping 3-mer subsequences to capture local sequence patterns.A pre-trained Doc2vec model maps these subsequences into fixeddimensional vectors,reducing feature dimensionality while extracting latent global semantic information via context learning.Both branches integrate residual networks(ResNet)and a self-attention mechanism:ResNet mitigates vanishing gradients through skip connections,preserving feature integrity,while self-attention adaptively assigns weights to focus on sequence regions most relevant to methylation prediction.This synergy enhances both feature learning and generalization capability.Results Across 11 tissues from humans,mice,and rats,m6A-PSRA consistently outperformed existing methods in accuracy(ACC)and area under the curve(AUC),achieving>90%ACC and>95%AUC in every tissue tested,indicating strong cross-species and cross-tissue adaptability.Validation on independent datasets—including three human cell lines(MOLM1,HEK293,A549)and a long-sequence dataset(m6A_IND,1001 nt)—confirmed stable performance across varied biological contexts and sequence lengths.Ablation studies demonstrated that the dual-branch architecture,residual network,and self-attention mechanism each contribute critically to performance,with their combination reducing interference between pathways.Motif analysis revealed an enrichment of m6A sites in guanine(G)and cytosine(C),consistent with known regulatory patterns,supporting the model’s biological plausibility.Conclusion m6A-PSRA effectively captures RNA sequence features,achieving high prediction accuracy and robust generalization across tissues and species,providing an efficient computational tool for m6A methylation site prediction.
