Reservoirs play a critical role in addressing water resources challenges.However,their vertical influence on the assembly mechanisms of different microbial communities,including prokaryotes and eukaryotes,remains uncl...Reservoirs play a critical role in addressing water resources challenges.However,their vertical influence on the assembly mechanisms of different microbial communities,including prokaryotes and eukaryotes,remains unclear.This study examined the vertical diversity patterns of abundant and rare subcommunities of prokaryotes and eukaryotes in an urban reservoir,using water depth as a geographical gradient and employing high-throughput sequencing.The impact of vertical environmental heterogeneity on community structure was quantified,and key drivers of these dynamics were identified.The results indicated that the urban reservoir exhibited statistically significant differences in the vertical distribution of water temperature and oxidation/reduction potential.The a-diversity of the abundant subcommunity displayed an opposing vertical pattern compared to that of the rare subcommunity,while the b-diversity for both subcommunities of prokaryotes and eukaryotes increased with water depth.Moreover,the distinct diversity patterns of abundant and rare subcommunities were associated with environmental heterogeneity and species adaptability.Notably,the b-diversity of the rare subcommunity of eukaryotes was primarily driven by species turnover in surface water,whereas nestedness became the dominant factor in deeper water.Furthermore,eukaryotic microbes exhibited a more pronounced response to changes in water depth than prokaryotes,consistent with the importance of heterogeneous selection to the eukaryotic community.Water temperature significantly affected the community composition of all groups,highlighting its importance in shaping community dynamics.This study provides valuable insights into the vertical distribution and assembly mechanisms of microbial communities in urban reservoirs,contributing to the protection and management of aquatic ecosystems under river regulation.展开更多
The application of industrial solid wastes as environmentally functional materials for air pollutants control has gained much attention in recent years due to its potential to reduce air pollution in a cost-effective ...The application of industrial solid wastes as environmentally functional materials for air pollutants control has gained much attention in recent years due to its potential to reduce air pollution in a cost-effective manner.In this review,we investigate the development of industrialwaste-based functional materials for various gas pollutant removal and consider the relevant reaction mechanism according to different types of industrial solid waste.We see a recent effort towards achieving high-performance environmental functional materials via chemical or physical modification,in which the active components,pore size,and phase structure can be altered.The review will discuss the potential of using industrial solid wastes,these modified materials,or synthesized materials from raw waste precursors for the removal of air pollutants,including SO_(2),NO_(x),Hg^(0),H_(2)S,VOCs,and CO_(2).The challenges still need to be addressed to realize this potential and the prospects for future research fully.The suggestions for future directions include determining the optimal composition of these materials,calculating the real reaction rate and turnover frequency,developing effective treatment methods,and establishing chemical component databases of raw industrial solid waste for catalysts/adsorbent preparation.展开更多
Enhancing soil organic matter characteristics,ameliorating physical structure,mitigating heavy metal toxicity,and hastening mineral weathering processes are crucial approaches to accomplish the transition of tailings ...Enhancing soil organic matter characteristics,ameliorating physical structure,mitigating heavy metal toxicity,and hastening mineral weathering processes are crucial approaches to accomplish the transition of tailings substrate to a soil-like substrate.The incorporation of biomass co-pyrolysis and plant colonization has been established to be a significant factor in soil substrate formation and soil pollutant remediation.Despite this,there is presently an absence of research efforts aimed at synergistically utilizing these two technologies to expedite the process of mining tailings soil substrate formation.The current study aimed to investigate the underlying mechanism of geochemical changes and rapid mineral weathering during the process of transforming tailings substrate into a soil-like substrate,under the combined effects of biomass co-smoldering pyrolysis and plant colonization.The findings of this study suggest that the incorporation of smoldering pyrolysis and plant colonization induces a high-temperature effect and biological effects,which enhance the physical and chemical properties of tailings,while simultaneously accelerating the rate of mineral weathering.Notable improvements include the amelioration of extreme pH levels,nutrient enrichment,the formation of aggregates,and an increase in enzyme activity,all of which collectively demonstrate the successful attainment of tailings substrate reconstruction.Evidence of the acceleratedweathering was verified by phase and surfacemorphology analysis using X-ray diffraction and scanning electron microscopy.Discovered corrosion and fragmentation on the surface ofminerals.The weathering resulted in corrosion and fragmentation of the surface of the treated mineral.This study confirms that co-smoldering pyrolysis of biomass,combined with plant colonization,can effectively promote the transformation of tailings into soil-like substrates.This method has can effectively address the key challenges that have previously hindered sustainable development of the mining industry and provides a novel approach for ecological restoration of tailings deposits.展开更多
This study employed a wet impregnation method to synthesize five types of Cu/HZSM-5 adsorbents with Si/Al ratios of 25,50,85,200,and 300,used for the removal of H_(2)S in lowtemperature,low-oxygen environments.The imp...This study employed a wet impregnation method to synthesize five types of Cu/HZSM-5 adsorbents with Si/Al ratios of 25,50,85,200,and 300,used for the removal of H_(2)S in lowtemperature,low-oxygen environments.The impact of different Si/Al ratios on the adsorption oxidative performance of Cu_(30)/HZSM-5–85 adsorbents was investigated.According to the performance test results,Cu_(30)/HZSM-5–85 exhibited the highest breakthrough capacity,reaching 231.75 mg H_(2)S/g_(sorbent).Cu/HZSM-5 sorbent maintains a strong ability to remove H_(2)S even under humid conditions and shows excellent water resistance.XRD,BET,and XPS results revealed that CuO is the primary active species,with Cu_(30)/HZSM-5–85 having the largest surface area and highest CuO content,providing more active sites for H_(2)S adsorption.H_(2)-TPR and O_(2)-TPD results confirmed that Cu_(30)/HZSM-5–85 sorbent exhibits outstanding redox properties and oxygen storage capacity,contributing to excellent oxygen transferability in the molecular sieve adsorption-oxidation process.With notable characteristics such as a large surface area,high desulfurization efficiency,and water resistance,Cu_(30)/HZSM-5–85 sorbents hold significant importance for industrial applications.展开更多
Objective Recent studies have highlighted the critical role of NUDT19 in the initiation,progression,and prognosis of specific cancer types.However,its involvement in pan-cancer analysis has not been fully characterize...Objective Recent studies have highlighted the critical role of NUDT19 in the initiation,progression,and prognosis of specific cancer types.However,its involvement in pan-cancer analysis has not been fully characterized.This study aims to systematically explore the expression patterns,clinical significance,and immune-related functions of NUDT19 in various cancer types through multi-omics analysis,further revealing its potential role in cancer,particularly its functional and therapeutic target value in leukemia.Methods To achieve this goal,various bioinformatics approaches were employed to evaluate the expression patterns,clinical significance,and immune-related functions of NUDT19 in tumors and normal tissues.Additionally,we analyzed the mutation characteristics of NUDT19 and its relationship with epigenetic modifications.Using the single-cell analysis tool SingleCellBase,we explored the distribution of NUDT19 across different cell subpopulations in tumors.To validate these findings,qRT-PCR was used to measure NUDT19 expression levels in specific tumor cell lines,and we established acute myeloid leukemia(AML)cell lines(HL-60 and THP-1)to conduct NUDT19 knockdown and overexpression experiments,assessing its effects on leukemia cell proliferation,apoptosis,and invasion.Results Pan-cancer analysis revealed the dysregulated expression of NUDT19 across multiple cancer types,which was closely associated with poor prognosis,clinical staging,and diagnostic markers.Furthermore,NUDT19 was significantly correlated with tumor biomarkers,immune-related genes,and immune cell infiltration in different cancers.Mutation analysis showed that multiple mutations in NUDT19 were significantly associated with epigenetic changes.Single-cell analysis revealed the heterogeneity of NUDT19 expression in cancer cells,suggesting its potentially diverse functional roles in different cell subpopulations.qRT-PCR experiments confirmed the significant upregulation of NUDT19 in various tumor cell lines.In AML cell lines,NUDT19 knockdown led to reduced cell proliferation and invasion,with increased apoptosis,while NUDT19 overexpression significantly enhanced cell proliferation and invasion while reducing apoptosis.Conclusion This study demonstrates the diverse roles of NUDT19 in various cancer types,with a particularly prominent functional role in leukemia.NUDT19 is not only associated with tumor initiation and progression but may also influence cancer progression through the regulation of immune microenvironment and epigenetic mechanisms.Our research highlights the potential of NUDT19 as a therapeutic target,particularly for targeted therapies in malignancies such as leukemia,with significant clinical application prospects.展开更多
Metal nanoparticle(NP_S)catalysts exhibit desirable activities in various catalytic reactions.However,the sintering of metal NPs at high-temperatures even in reducing atmospheres limits its practical application.In th...Metal nanoparticle(NP_S)catalysts exhibit desirable activities in various catalytic reactions.However,the sintering of metal NPs at high-temperatures even in reducing atmospheres limits its practical application.In this work,we successfully synthesized TPA-ZSM-5 with pit-type defects by treating the ZSM-5 with tetrahydroxy ammonium hydroxide(TPAOH),which was then used as a support to prepare Ag-based and Cu-based catalysts.Stability testing results show that the Ag/TPA-ZSM-5 catalyst treated at 800℃with H_(2) could maintain the high performance in NH_(3)-SCO and the Cu/TPA-ZSM-5 catalyst treated at 900℃ with N_(2) could maintained its excellent activity in NH_(3)-SCR,however,the activities of Ag/ZSM-5 and Cu/ZSM-5 were drastically decreased or even deactivated after high-temperature treatment.In addition,a series of characterization analyses revealed that the excellent thermal stability is attribute to the presence of pit-type defects in the TPA-ZSM-5 as physical barriers to slow down or even inhibit the Ag NPs and Cu NPs sintering process.The strategy of using the pit-type defects to inhibit the sintering of metal NPs and improve the thermal stability can greatly enhance the practical application of catalysts.展开更多
To improve the activity of Co/Al_(2)O_(3)catalysts in selective catalytic oxidation of ammonia(NH_(3)-SCO),valence state and size of active centers of Al_(2)O_(3)-supported Co catalysts were adjusted by conducting H_(...To improve the activity of Co/Al_(2)O_(3)catalysts in selective catalytic oxidation of ammonia(NH_(3)-SCO),valence state and size of active centers of Al_(2)O_(3)-supported Co catalysts were adjusted by conducting H_(2)reduction pretreatment.The NH_(3)-SCO activity of the adjusted 2Co/Al_(2)O_(3)catalyst was substantially improved,outperforming other catalysts with higher Co-loading.Fresh Co/Al_(2)O_(3)catalysts exhibited multitemperature reduction processes,enabling the control of the valence state of the Co-active centers by adjusting the reduction temperature.Changes in the state of the Co-active centers also led to differences in redox capacity of the catalysts,resulting in different reaction mechanisms for NH_(3)-SCO.However,in situ diffuse reflectance infrared Fourier transform spectra revealed that an excessive O_(2)activation capacity caused overoxidation of NH_(3)to NO and NO_(2).The NH_(3)-SCO activity of the 2Co/Al_(2)O_(3)catalyst with low redox capacity was successfully increased while controlling and optimizing the N_(2)selectivity by modulating the active centers via H_(2)pretreatment,which is a universalmethod used for enhancing the redox properties of catalysts.Thus,this method has great potential for application in the design of inexpensive and highly active catalysts.展开更多
Biomass burning(BB)emits carbonaceous aerosols that significantly influence air quality in Southwest China during spring.To further understand the characteristics of spring BB and its original contribution to organic ...Biomass burning(BB)emits carbonaceous aerosols that significantly influence air quality in Southwest China during spring.To further understand the characteristics of spring BB and its original contribution to organic carbon(OC),daily fine particulate matter(PM_(2.5))samples were collected from March to May 2022 in Pu'er,Southwest China.The concentrations of OC,elemental carbon(EC),levoglucosan(Lev),and potassium from BB(K+BB)during the study period ranged from 5.3 to 31.2μg/m^(3),0.86-13.1μg/m^(3),0.06-0.82μg/m^(3),and 0.05-2.88μg/m^(3),respectively.To eliminate the effects of Lev degradation,this study uses the Aging of Air Mass(AAM)index to correct the atmospheric concentration of Lev and combines Bayesian mixture modeling with a molecular tracer method to assess the original contribution of BB to OC.The results indicated that the AAM index was 0.18±0.05,indicating that the degradation of Lev reached 82%.When considering the degradation of levoglucosan in the atmosphere,the primary source of BB aerosols was crop-straw combustion(71.1%),followed by the combustion of certain hardwoods and softwoods(24.9%)and grasses(4.0%).The original contribution of BB to OC was 62.4%,which was much greater than the contribution when levoglucosan degradation(23.7%)was ignored.The air mass inverse trajectories and Moderate Resolution Imaging Spectroradiometer(MODIS)fire hotspots indicated that the BB plume from Southeast Asia during spring could influence PM_(2.5)long-range transport in remote locations,and the contribution could reach 82%in Southwest China.展开更多
Large-scale damming has emerged as a prevalent global trend,significantly impacting nutrient transport and transformation,as well as the downstream ecological environment.Nitrogen and phosphorus are fundamental elemen...Large-scale damming has emerged as a prevalent global trend,significantly impacting nutrient transport and transformation,as well as the downstream ecological environment.Nitrogen and phosphorus are fundamental elements of primary productivity in aquatic ecosystems and serve as key limiting factors in reservoir eutrophication.This review focuses on the impact of damming on the transport and transformation of nitrogen and phosphorus,regarding changes in nutrient concentrations,fluxes,and proportions.Spatial changes in nitrogen and phosphorus concentrations primarily occur at the inlet and outlet of reservoirs,while temporal changes often exhibit seasonal patterns.At a global scale,phosphorus is preferentially removed from reservoirs compared to nitrogen.The factors influencing the transport and transformation processes of nitrogen and phosphorus in reservoirs include the physicochemical properties of water bodies and human activities.Additionally,nitrogen dynamics are affected by reservoir age,storage capacity,and water storage regulation modes,whereas phosphorus dynamics are also influenced by hydrodynamic conditions.Finally,this review summarizes the impact of damming on the downstream ecological environment and outlines future research directions,providing theoretical support for the management of river–reservoir ecosystems and promoting the green and sustainable development of hydropower in the context of carbon peaking and carbon neutrality goals.展开更多
Sand rice(Agriophyllum squarrosum),a pioneering annual plant thriving in deserts and sandy regions throughout the Asian interior,is believed to be a potential food and forage crop due to its significant nutritional an...Sand rice(Agriophyllum squarrosum),a pioneering annual plant thriving in deserts and sandy regions throughout the Asian interior,is believed to be a potential food and forage crop due to its significant nutritional and medicinal values.Previous metabolomics analyses have revealed that sand rice contains abundant flavonoid components,which are known for their wide applications in cosmetics,food,and pharmaceuticals.To optimize the use of flavonoids in sand rice,in this study,the response surface methodology(RSM)was selected to determine the optimal ultrasonic-assisted extraction(UAE)criteria for flavonoids extraction from the aerial part of sand rice firstly.Statistical analyses unveiled the optimum parameters for flavonoids extraction fromsand rice could be 62%of ethanol concentration,1:43 solid-toliquid ratio,160Wfor ultrasound power,and 52℃for extraction temperature with extraction time of 12 min.Under this condition,the experiment optimumtotal flavonoid yield could reach at 15.24 mg/g,which was correspond to the maximum predicted value of RSM with 15.22 mg/g.Subsequently,the antifungal efficacy of these extracts was evaluated against three common plant pathogenic fungi,showing a significant inhibitory effect with the highest rate of inhibition reaching 25.3%at a concentration of 4 mg/mL,underscoring its potential as a natural antimicrobial agent.This studywill not only provide a powerful method to extract flavonoids froma desert resource plant,but also pave the way for industrial development and application of the promising desert plants with high nutritional and medicinal values.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
The removal of arsenic from water and wastewater is obligatory. Resin is one of the most effective adsorbents for the removal of arsenic. In order to improve the adsorption capacity of resin, a new cerium-loaded catio...The removal of arsenic from water and wastewater is obligatory. Resin is one of the most effective adsorbents for the removal of arsenic. In order to improve the adsorption capacity of resin, a new cerium-loaded cation exchange resin arsenic adsorbent was prepared by impregnating cerium into the cation exchange resin. Batch adsorption experiments under various conditions, such as time, temperature, pH and with coexisting ions were carried out to evaluate the adsorption characteristics of cerium-loaded resin in the removal of As(V) and As(III) from aqueous solutions. The results showed that the adsorption kinetics of As(V) and As(III) obeyed a pseudo second-order kinetic model and the adsorption rate constants were 0.3159 and 0.5215 g.mg-1-min-1, respectively. The adsorption of As(V) followed the Freundlich adsorption isotherm model and the adsorption isotherm data for As(III) fitted well to the Langmuir equation model. The adsorption capacities were 1.0278 mg/g for As(V) and 2.5297 mg/g for As(Ill). Both the adsorption of As(V) and As(Ill) were found to be pH sensitive and the optimum pH was found to be 5-6. Except for the phosphate ion, the coexisting anionics, such as nitrate, chlorate, sulphate and carbonate, showed no remarkable effect on As(V) and As(ill) adsorption. The desorption and regeneration study showed that the adsorption capacity of Ce-loaded resin for As(V) and As(Ill) could be restored to 97.80% and 69.61%, respectively, using 0.5 moFL sodium hydroxide solution.展开更多
Phosphogypsum(PG) is a solid waste produced in the phosphate fertilizer industry and is environmentally harmful.The decomposition of PG to recycle calcium and sulfur is a proper way to reutilize PG. Current work aims ...Phosphogypsum(PG) is a solid waste produced in the phosphate fertilizer industry and is environmentally harmful.The decomposition of PG to recycle calcium and sulfur is a proper way to reutilize PG. Current work aims at enriching the basic theory of coal decomposition process of PG. The emphasis was laid on the exploration of impact of main impurities on the process. On the other hand, according to Reaction Module, Equilib Module, and Phase Diagram Module of FactS age, the simulation computation was done on the systems of pure gypsum mixed with coal,with or without impurities for avoiding other impurities interference. Later, possible reactions in the process were deduced. Additionally, experiments were conducted in a TG-DTA integrated thermal gravimetric analyzer and a tube furnace. The products from the experiments were characterized and analyzed to verify the accuracy of theoretical calculations. The results showed that these impurities can change the decomposition process of PG. For example, aluminum oxide was transformed to calcium sulfoaluminate, while iron oxide was transformed to dicalcium ferrite. Furthermore, the results help to further improve the basic theory of phosphogypsum decomposition.展开更多
We prepared a kind of metal oxide-modified walnut-shell activated carbon(MWAC) by KOH chemical activation method and used for PH_3 adsorption removal. Meanwhile, the PH_3 adsorption equilibrium was investigated experi...We prepared a kind of metal oxide-modified walnut-shell activated carbon(MWAC) by KOH chemical activation method and used for PH_3 adsorption removal. Meanwhile, the PH_3 adsorption equilibrium was investigated experimentally and fitted by the Toth equation, and the isosteric heat of PH_3 adsorption was calculated by the Clausius-Clapeyron Equation. The exhausted MWAC was regenerated by water washing and air drying. Moreover, the properties of five different samples were characterized by N_2 adsorption isotherm, SEM/EDS, XPS, and FTIR. The results showed that the maximum PH_3 equilibrium adsorption capacity was 595.56 mg/g. The MWAC had an energetically heterogeneous surface due to values of isosteric heat of adsorption ranging from 43 to 90 kJ/mol. The regeneration method provided an effective way for both adsorption species recycling and exhausted carbon regeneration. The high removal efficiency and big equilibrium adsorption capacity for PH_3 adsorption on the MWAC were related to its large surface area and high oxidation activity in PH_3 adsorption-oxidation to H_3 PO_4 and P_2 O_5. Furthermore, a possible PH_3 adsorption mechanism was proposed.展开更多
A series of copper-based activated carbon (AC) adsorbents were prepared in order to investigate the effect of Zn, Ce addition on Cu-based AC adsorbent for phosphine (PH3) adsorption removal from yellow phosphorous tai...A series of copper-based activated carbon (AC) adsorbents were prepared in order to investigate the effect of Zn, Ce addition on Cu-based AC adsorbent for phosphine (PH3) adsorption removal from yellow phosphorous tail gas. N2 adsorption isotherm and X-ray diffrac-tion (XRD) results suggested that the addition of Zn could increase the adsorbent ultramicropores, decrease the adsorbent supermicropores and the adsorbent average pore diameter. Therefore it enhanced the PH3 adsorption capacity. Appropriate amoun...展开更多
The absorbent composing of Bayer red mud and water was prepared and applied to removing SO2 from flue gas.Effects of the ratio of liquid to solid(L/S),the absorption temperature,the inlet SO2 concentration,the O2 conc...The absorbent composing of Bayer red mud and water was prepared and applied to removing SO2 from flue gas.Effects of the ratio of liquid to solid(L/S),the absorption temperature,the inlet SO2 concentration,the O2 concentration,SO4^2-and other different components of Bayer red mud on desulfurization were conducted.The mechanism of flue gas desulfurization was also established.The results indicated that L/S was the prominent factor,followed by the inlet SO2 concentration and the temperature was the least among them.The optimum condition was as follows:L/S,the temperature and the SO2 concentration were 20:1,25℃and 1000 mg/m^3,respectively,under the gas flow of 1.5 L/min.The desulfurization efficiency was not significantly influenced when O2 concentration was above 7%.The accumulation of SO4^2-inhibited the desulfurization efficiency.The alkali absorption and metal ions liquid catalytic oxidation were involved in the process,which accounted for 98.61%.展开更多
In this work, a series of coal-based active carbon (CAC) catalysts loaded by A1203 were prepared by sol-gel method and used for the simulta- neous catalytic hydrolysis of carbonyl sulfide (COS) and carbon disulfi...In this work, a series of coal-based active carbon (CAC) catalysts loaded by A1203 were prepared by sol-gel method and used for the simulta- neous catalytic hydrolysis of carbonyl sulfide (COS) and carbon disulfide (CS2) at relatively low temperatures of 30-70 ℃. The influences of calcinations temperatures and operation conditions such as: reaction temperature, 02 concentration, gas hourly space velocity (GHSV) and relative humidity (RH) were also discussed respectively. The results showed that catalysts with 5.0 wt% A1203 calcined at 300 ℃ had supe- rior activity for the simultaneous catalytic hydrolysis of COS and CS2. When the reaction temperature was above 50 ℃, catalytic hydrolysis activity of COS could be enhanced but that of CS2 was inhibited. Too high RH could make the catalytic hydrolysis activities of COS and CS2 decrease. A small amount of 02 introduction could enhance the simultaneous catalytic hydrolysis activities of COS and CS2.展开更多
Pyrite is the most abundant sulfide semiconductor mineral with excellent optical properties.However,few reports have investigated its photocatalytic activity because of the low photogenerated carrier separation effici...Pyrite is the most abundant sulfide semiconductor mineral with excellent optical properties.However,few reports have investigated its photocatalytic activity because of the low photogenerated carrier separation efficiency.In this work,a Z-scheme FeS_(2)/Fe_(2)O_(3)composite photocatalyst was fabricated in situ via structural transformation of pyrite through heat treatment.A remarkably enhanced photocatalytic performance was observed over the FeS_(2)/Fe_(2)O_(3)composite photocatalyst.Compared with the pristine pyrite,the degradation efficiency of carbamazepine(CBZ)reached 65%at the added hexavalent chromium(Cr(Ⅵ))concentration of 20 mg/L and the Cr(Ⅵ)was nearly completely reduced in the mixed system using FeS_(2)/Fe_(2)O_(3)within 30 min under simulated solar light irradiation.The enhanced photocatalytic activity can be attributed to the efficient separation and transfer of photogenerated carriers in the FeS_(2)/Fe_(2)O_(3)composite photocatalyst.This facilitated the generation of·OH,hole(h^(+))and·O_(2)^(-)species,which participated in the photocatalytic reaction with CBZ.Based on the measurement of the active species and electric properties,a Z-scheme electron transfer pathway was proposed for the FeS_(2)/Fe_(2)O_(3)composite photocatalyst.This work broadens the application potential of pyrite in environmental remediation.展开更多
A new method for analysis of trace mercury in water samples was developed, based on the combination of preconcentration/separation using dithizone-modified nanometer titanium dioxide (TiO2) as a solid phase extracta...A new method for analysis of trace mercury in water samples was developed, based on the combination of preconcentration/separation using dithizone-modified nanometer titanium dioxide (TiO2) as a solid phase extractant and determination by cold vapor atomic adsorption spectrometry (CVAAS). Dithizone was dissolved with alcohol and loaded on the surface of nano-sized TiO2 powders by stirring. The static adsorption behavior of Hg^2+on the dithizone-modified nanoparficles was investigated in detail. It was found that excellent adsorption ratio for Hg^2+ could be obtained in the pH range of 7-8 with an oscillation time of 15 rain, and a 5 mL of 3.5 mol·L^-1 HCI solution could quantitatively elute Hg^2+ from nanometer TiO2 powder. Common coexisting ions caused no obvious influence on the determination of mercury. The mechanisms for the adsorption and desorption were discussed. The detection limit (30) for Hg^2+ was calculated to be 5 ng·L^-1. The proposed method was applied to the determination of Hg^2+ in a mineral water sample and a Zhujiang River water sample. By the standard addition method, the average recoveries were found to be 94.4%-108.3% with RSD (n = 5) of 2.9%-3.5%.展开更多
The sol–gel method was used to synthesize a series of metal oxides-supported activated carbon fiber (ACF) and the simultaneous catalytic hydrolysis activity of carbonyl sulfide (COS)and carbon disulfide (CS2) at rela...The sol–gel method was used to synthesize a series of metal oxides-supported activated carbon fiber (ACF) and the simultaneous catalytic hydrolysis activity of carbonyl sulfide (COS)and carbon disulfide (CS2) at relatively low temperatures of 60°C was tested.The effects of preparation conditions on the catalyst properties were investigated,including the kinds and amount of metal oxides and calcination temperatures.The activity tests indicated that catalysts with 5 wt.%Ni after calcining at 400°C (Ni(5)/ACF(400)) had the best performance for the simultaneous catalytic hydrolysis of COS and CS2.The surface and structure properties of prepared ACF were characterized by scanning electron microscope-energy disperse spectroscopy (SEM-EDS),Brunauer–Emmett–Teller (BET),X-ray diffraction (XRD),carbon dioxidetemperature programmed desorption (CO2-TPD) and diffuse reflectance Fourier transform infrared reflection (DRFTIR).And the metal cation defects were researched by electron paramagnetic resonance (EPR) method.The characterization results showed that the supporting of Ni on the ACF made the ACF catalyst show alkaline and increased the specific surface area and the number of micropores,then improved catalytic hydrolysis activity.The DRFTIR results revealed that-OH species could facilitate the hydrolysis of COS and CS2;-COO and-C–O species could facilitate the oxidation of catalytic hydrolysate H2S.And the EPR results showed that high calcination temperature conditions provide more active reaction center for the COS and CS2 adsorption.展开更多
基金supported by the Key Program of the National Natural Science Foundation of China(Grant No.92047201)the Fundamental Research Funds for the Central Universities(Grant No.B230201026)+1 种基金the National Natural Science Foundation of China(Grants No.42377054 and 42007149)the Open Project of Jiangsu Key Laboratory for Eco-Agricultural Biotechnology around Hongze Lake(Grant No.HZHLAB2301).
文摘Reservoirs play a critical role in addressing water resources challenges.However,their vertical influence on the assembly mechanisms of different microbial communities,including prokaryotes and eukaryotes,remains unclear.This study examined the vertical diversity patterns of abundant and rare subcommunities of prokaryotes and eukaryotes in an urban reservoir,using water depth as a geographical gradient and employing high-throughput sequencing.The impact of vertical environmental heterogeneity on community structure was quantified,and key drivers of these dynamics were identified.The results indicated that the urban reservoir exhibited statistically significant differences in the vertical distribution of water temperature and oxidation/reduction potential.The a-diversity of the abundant subcommunity displayed an opposing vertical pattern compared to that of the rare subcommunity,while the b-diversity for both subcommunities of prokaryotes and eukaryotes increased with water depth.Moreover,the distinct diversity patterns of abundant and rare subcommunities were associated with environmental heterogeneity and species adaptability.Notably,the b-diversity of the rare subcommunity of eukaryotes was primarily driven by species turnover in surface water,whereas nestedness became the dominant factor in deeper water.Furthermore,eukaryotic microbes exhibited a more pronounced response to changes in water depth than prokaryotes,consistent with the importance of heterogeneous selection to the eukaryotic community.Water temperature significantly affected the community composition of all groups,highlighting its importance in shaping community dynamics.This study provides valuable insights into the vertical distribution and assembly mechanisms of microbial communities in urban reservoirs,contributing to the protection and management of aquatic ecosystems under river regulation.
基金supported by National Natural Science Foundation of China(Grant No.52270106 and 22266021)Yunnan Major Scientific and Technological Projects(grant No.202202AG050005)Yunnan Fundamental Research Projects(grant No.202201AT070116).
文摘The application of industrial solid wastes as environmentally functional materials for air pollutants control has gained much attention in recent years due to its potential to reduce air pollution in a cost-effective manner.In this review,we investigate the development of industrialwaste-based functional materials for various gas pollutant removal and consider the relevant reaction mechanism according to different types of industrial solid waste.We see a recent effort towards achieving high-performance environmental functional materials via chemical or physical modification,in which the active components,pore size,and phase structure can be altered.The review will discuss the potential of using industrial solid wastes,these modified materials,or synthesized materials from raw waste precursors for the removal of air pollutants,including SO_(2),NO_(x),Hg^(0),H_(2)S,VOCs,and CO_(2).The challenges still need to be addressed to realize this potential and the prospects for future research fully.The suggestions for future directions include determining the optimal composition of these materials,calculating the real reaction rate and turnover frequency,developing effective treatment methods,and establishing chemical component databases of raw industrial solid waste for catalysts/adsorbent preparation.
基金supported by the National Natural Science Foundation of China(No.52060011).
文摘Enhancing soil organic matter characteristics,ameliorating physical structure,mitigating heavy metal toxicity,and hastening mineral weathering processes are crucial approaches to accomplish the transition of tailings substrate to a soil-like substrate.The incorporation of biomass co-pyrolysis and plant colonization has been established to be a significant factor in soil substrate formation and soil pollutant remediation.Despite this,there is presently an absence of research efforts aimed at synergistically utilizing these two technologies to expedite the process of mining tailings soil substrate formation.The current study aimed to investigate the underlying mechanism of geochemical changes and rapid mineral weathering during the process of transforming tailings substrate into a soil-like substrate,under the combined effects of biomass co-smoldering pyrolysis and plant colonization.The findings of this study suggest that the incorporation of smoldering pyrolysis and plant colonization induces a high-temperature effect and biological effects,which enhance the physical and chemical properties of tailings,while simultaneously accelerating the rate of mineral weathering.Notable improvements include the amelioration of extreme pH levels,nutrient enrichment,the formation of aggregates,and an increase in enzyme activity,all of which collectively demonstrate the successful attainment of tailings substrate reconstruction.Evidence of the acceleratedweathering was verified by phase and surfacemorphology analysis using X-ray diffraction and scanning electron microscopy.Discovered corrosion and fragmentation on the surface ofminerals.The weathering resulted in corrosion and fragmentation of the surface of the treated mineral.This study confirms that co-smoldering pyrolysis of biomass,combined with plant colonization,can effectively promote the transformation of tailings into soil-like substrates.This method has can effectively address the key challenges that have previously hindered sustainable development of the mining industry and provides a novel approach for ecological restoration of tailings deposits.
基金supported by the National Natural Science Foundation of China(Nos.52270106 and 22266021)Yunnan Major Scientific and Technological Projects(No.202202AG050005)Yunnan Fundamental Research Projects(No.202201AT070116).
文摘This study employed a wet impregnation method to synthesize five types of Cu/HZSM-5 adsorbents with Si/Al ratios of 25,50,85,200,and 300,used for the removal of H_(2)S in lowtemperature,low-oxygen environments.The impact of different Si/Al ratios on the adsorption oxidative performance of Cu_(30)/HZSM-5–85 adsorbents was investigated.According to the performance test results,Cu_(30)/HZSM-5–85 exhibited the highest breakthrough capacity,reaching 231.75 mg H_(2)S/g_(sorbent).Cu/HZSM-5 sorbent maintains a strong ability to remove H_(2)S even under humid conditions and shows excellent water resistance.XRD,BET,and XPS results revealed that CuO is the primary active species,with Cu_(30)/HZSM-5–85 having the largest surface area and highest CuO content,providing more active sites for H_(2)S adsorption.H_(2)-TPR and O_(2)-TPD results confirmed that Cu_(30)/HZSM-5–85 sorbent exhibits outstanding redox properties and oxygen storage capacity,contributing to excellent oxygen transferability in the molecular sieve adsorption-oxidation process.With notable characteristics such as a large surface area,high desulfurization efficiency,and water resistance,Cu_(30)/HZSM-5–85 sorbents hold significant importance for industrial applications.
文摘Objective Recent studies have highlighted the critical role of NUDT19 in the initiation,progression,and prognosis of specific cancer types.However,its involvement in pan-cancer analysis has not been fully characterized.This study aims to systematically explore the expression patterns,clinical significance,and immune-related functions of NUDT19 in various cancer types through multi-omics analysis,further revealing its potential role in cancer,particularly its functional and therapeutic target value in leukemia.Methods To achieve this goal,various bioinformatics approaches were employed to evaluate the expression patterns,clinical significance,and immune-related functions of NUDT19 in tumors and normal tissues.Additionally,we analyzed the mutation characteristics of NUDT19 and its relationship with epigenetic modifications.Using the single-cell analysis tool SingleCellBase,we explored the distribution of NUDT19 across different cell subpopulations in tumors.To validate these findings,qRT-PCR was used to measure NUDT19 expression levels in specific tumor cell lines,and we established acute myeloid leukemia(AML)cell lines(HL-60 and THP-1)to conduct NUDT19 knockdown and overexpression experiments,assessing its effects on leukemia cell proliferation,apoptosis,and invasion.Results Pan-cancer analysis revealed the dysregulated expression of NUDT19 across multiple cancer types,which was closely associated with poor prognosis,clinical staging,and diagnostic markers.Furthermore,NUDT19 was significantly correlated with tumor biomarkers,immune-related genes,and immune cell infiltration in different cancers.Mutation analysis showed that multiple mutations in NUDT19 were significantly associated with epigenetic changes.Single-cell analysis revealed the heterogeneity of NUDT19 expression in cancer cells,suggesting its potentially diverse functional roles in different cell subpopulations.qRT-PCR experiments confirmed the significant upregulation of NUDT19 in various tumor cell lines.In AML cell lines,NUDT19 knockdown led to reduced cell proliferation and invasion,with increased apoptosis,while NUDT19 overexpression significantly enhanced cell proliferation and invasion while reducing apoptosis.Conclusion This study demonstrates the diverse roles of NUDT19 in various cancer types,with a particularly prominent functional role in leukemia.NUDT19 is not only associated with tumor initiation and progression but may also influence cancer progression through the regulation of immune microenvironment and epigenetic mechanisms.Our research highlights the potential of NUDT19 as a therapeutic target,particularly for targeted therapies in malignancies such as leukemia,with significant clinical application prospects.
基金supported by the National Natural Science Foundation of China(No.52370113)Yunnan Fundamental Research Projects(No.202101BE070001-001)。
文摘Metal nanoparticle(NP_S)catalysts exhibit desirable activities in various catalytic reactions.However,the sintering of metal NPs at high-temperatures even in reducing atmospheres limits its practical application.In this work,we successfully synthesized TPA-ZSM-5 with pit-type defects by treating the ZSM-5 with tetrahydroxy ammonium hydroxide(TPAOH),which was then used as a support to prepare Ag-based and Cu-based catalysts.Stability testing results show that the Ag/TPA-ZSM-5 catalyst treated at 800℃with H_(2) could maintain the high performance in NH_(3)-SCO and the Cu/TPA-ZSM-5 catalyst treated at 900℃ with N_(2) could maintained its excellent activity in NH_(3)-SCR,however,the activities of Ag/ZSM-5 and Cu/ZSM-5 were drastically decreased or even deactivated after high-temperature treatment.In addition,a series of characterization analyses revealed that the excellent thermal stability is attribute to the presence of pit-type defects in the TPA-ZSM-5 as physical barriers to slow down or even inhibit the Ag NPs and Cu NPs sintering process.The strategy of using the pit-type defects to inhibit the sintering of metal NPs and improve the thermal stability can greatly enhance the practical application of catalysts.
基金supported by the National Natural Science Foundation of China(No.52260013)Yunnan Major Scientific and Technological Projects(No.202202AG050005).
文摘To improve the activity of Co/Al_(2)O_(3)catalysts in selective catalytic oxidation of ammonia(NH_(3)-SCO),valence state and size of active centers of Al_(2)O_(3)-supported Co catalysts were adjusted by conducting H_(2)reduction pretreatment.The NH_(3)-SCO activity of the adjusted 2Co/Al_(2)O_(3)catalyst was substantially improved,outperforming other catalysts with higher Co-loading.Fresh Co/Al_(2)O_(3)catalysts exhibited multitemperature reduction processes,enabling the control of the valence state of the Co-active centers by adjusting the reduction temperature.Changes in the state of the Co-active centers also led to differences in redox capacity of the catalysts,resulting in different reaction mechanisms for NH_(3)-SCO.However,in situ diffuse reflectance infrared Fourier transform spectra revealed that an excessive O_(2)activation capacity caused overoxidation of NH_(3)to NO and NO_(2).The NH_(3)-SCO activity of the 2Co/Al_(2)O_(3)catalyst with low redox capacity was successfully increased while controlling and optimizing the N_(2)selectivity by modulating the active centers via H_(2)pretreatment,which is a universalmethod used for enhancing the redox properties of catalysts.Thus,this method has great potential for application in the design of inexpensive and highly active catalysts.
基金supported by the Basic Research Key Project of Science and Technology Department of Yunnan Province(No.202401AS070116)the National Natural Science Foundation of China(No.21966016)。
文摘Biomass burning(BB)emits carbonaceous aerosols that significantly influence air quality in Southwest China during spring.To further understand the characteristics of spring BB and its original contribution to organic carbon(OC),daily fine particulate matter(PM_(2.5))samples were collected from March to May 2022 in Pu'er,Southwest China.The concentrations of OC,elemental carbon(EC),levoglucosan(Lev),and potassium from BB(K+BB)during the study period ranged from 5.3 to 31.2μg/m^(3),0.86-13.1μg/m^(3),0.06-0.82μg/m^(3),and 0.05-2.88μg/m^(3),respectively.To eliminate the effects of Lev degradation,this study uses the Aging of Air Mass(AAM)index to correct the atmospheric concentration of Lev and combines Bayesian mixture modeling with a molecular tracer method to assess the original contribution of BB to OC.The results indicated that the AAM index was 0.18±0.05,indicating that the degradation of Lev reached 82%.When considering the degradation of levoglucosan in the atmosphere,the primary source of BB aerosols was crop-straw combustion(71.1%),followed by the combustion of certain hardwoods and softwoods(24.9%)and grasses(4.0%).The original contribution of BB to OC was 62.4%,which was much greater than the contribution when levoglucosan degradation(23.7%)was ignored.The air mass inverse trajectories and Moderate Resolution Imaging Spectroradiometer(MODIS)fire hotspots indicated that the BB plume from Southeast Asia during spring could influence PM_(2.5)long-range transport in remote locations,and the contribution could reach 82%in Southwest China.
基金supported by the General Project of the National Natural Science Foundation of China(Grant No.42377054)the National Natural Science Fund for Young Scholars(Grant No.42007149)the Key Project of the Major Research Plan of the National Natural Science Foundation of China(Grant No.92047201).
文摘Large-scale damming has emerged as a prevalent global trend,significantly impacting nutrient transport and transformation,as well as the downstream ecological environment.Nitrogen and phosphorus are fundamental elements of primary productivity in aquatic ecosystems and serve as key limiting factors in reservoir eutrophication.This review focuses on the impact of damming on the transport and transformation of nitrogen and phosphorus,regarding changes in nutrient concentrations,fluxes,and proportions.Spatial changes in nitrogen and phosphorus concentrations primarily occur at the inlet and outlet of reservoirs,while temporal changes often exhibit seasonal patterns.At a global scale,phosphorus is preferentially removed from reservoirs compared to nitrogen.The factors influencing the transport and transformation processes of nitrogen and phosphorus in reservoirs include the physicochemical properties of water bodies and human activities.Additionally,nitrogen dynamics are affected by reservoir age,storage capacity,and water storage regulation modes,whereas phosphorus dynamics are also influenced by hydrodynamic conditions.Finally,this review summarizes the impact of damming on the downstream ecological environment and outlines future research directions,providing theoretical support for the management of river–reservoir ecosystems and promoting the green and sustainable development of hydropower in the context of carbon peaking and carbon neutrality goals.
基金support received from the Lanzhou Youth Science and Technology Talent Innovation Project(Grant No.:2023-QN-140)National Natural Science Foundation of China(Grant Nos.:31901079,32171608,32271695 and 32201378)the Chinese Academy of Sciences Strategic Biological Resources Program(Grant No.:KFJ-BRP-007-015).
文摘Sand rice(Agriophyllum squarrosum),a pioneering annual plant thriving in deserts and sandy regions throughout the Asian interior,is believed to be a potential food and forage crop due to its significant nutritional and medicinal values.Previous metabolomics analyses have revealed that sand rice contains abundant flavonoid components,which are known for their wide applications in cosmetics,food,and pharmaceuticals.To optimize the use of flavonoids in sand rice,in this study,the response surface methodology(RSM)was selected to determine the optimal ultrasonic-assisted extraction(UAE)criteria for flavonoids extraction from the aerial part of sand rice firstly.Statistical analyses unveiled the optimum parameters for flavonoids extraction fromsand rice could be 62%of ethanol concentration,1:43 solid-toliquid ratio,160Wfor ultrasound power,and 52℃for extraction temperature with extraction time of 12 min.Under this condition,the experiment optimumtotal flavonoid yield could reach at 15.24 mg/g,which was correspond to the maximum predicted value of RSM with 15.22 mg/g.Subsequently,the antifungal efficacy of these extracts was evaluated against three common plant pathogenic fungi,showing a significant inhibitory effect with the highest rate of inhibition reaching 25.3%at a concentration of 4 mg/mL,underscoring its potential as a natural antimicrobial agent.This studywill not only provide a powerful method to extract flavonoids froma desert resource plant,but also pave the way for industrial development and application of the promising desert plants with high nutritional and medicinal values.
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National Natural Science Foundation of China(21077048)the Analysis and Testing Foundation of Kunming University of Science and Technology(2010177)
文摘The removal of arsenic from water and wastewater is obligatory. Resin is one of the most effective adsorbents for the removal of arsenic. In order to improve the adsorption capacity of resin, a new cerium-loaded cation exchange resin arsenic adsorbent was prepared by impregnating cerium into the cation exchange resin. Batch adsorption experiments under various conditions, such as time, temperature, pH and with coexisting ions were carried out to evaluate the adsorption characteristics of cerium-loaded resin in the removal of As(V) and As(III) from aqueous solutions. The results showed that the adsorption kinetics of As(V) and As(III) obeyed a pseudo second-order kinetic model and the adsorption rate constants were 0.3159 and 0.5215 g.mg-1-min-1, respectively. The adsorption of As(V) followed the Freundlich adsorption isotherm model and the adsorption isotherm data for As(III) fitted well to the Langmuir equation model. The adsorption capacities were 1.0278 mg/g for As(V) and 2.5297 mg/g for As(Ill). Both the adsorption of As(V) and As(Ill) were found to be pH sensitive and the optimum pH was found to be 5-6. Except for the phosphate ion, the coexisting anionics, such as nitrate, chlorate, sulphate and carbonate, showed no remarkable effect on As(V) and As(ill) adsorption. The desorption and regeneration study showed that the adsorption capacity of Ce-loaded resin for As(V) and As(Ill) could be restored to 97.80% and 69.61%, respectively, using 0.5 moFL sodium hydroxide solution.
基金Supported by the National Natural Science Foundation of China(21666016)
文摘Phosphogypsum(PG) is a solid waste produced in the phosphate fertilizer industry and is environmentally harmful.The decomposition of PG to recycle calcium and sulfur is a proper way to reutilize PG. Current work aims at enriching the basic theory of coal decomposition process of PG. The emphasis was laid on the exploration of impact of main impurities on the process. On the other hand, according to Reaction Module, Equilib Module, and Phase Diagram Module of FactS age, the simulation computation was done on the systems of pure gypsum mixed with coal,with or without impurities for avoiding other impurities interference. Later, possible reactions in the process were deduced. Additionally, experiments were conducted in a TG-DTA integrated thermal gravimetric analyzer and a tube furnace. The products from the experiments were characterized and analyzed to verify the accuracy of theoretical calculations. The results showed that these impurities can change the decomposition process of PG. For example, aluminum oxide was transformed to calcium sulfoaluminate, while iron oxide was transformed to dicalcium ferrite. Furthermore, the results help to further improve the basic theory of phosphogypsum decomposition.
基金Funded by the National Natural Science Foundation of China(51566017)
文摘We prepared a kind of metal oxide-modified walnut-shell activated carbon(MWAC) by KOH chemical activation method and used for PH_3 adsorption removal. Meanwhile, the PH_3 adsorption equilibrium was investigated experimentally and fitted by the Toth equation, and the isosteric heat of PH_3 adsorption was calculated by the Clausius-Clapeyron Equation. The exhausted MWAC was regenerated by water washing and air drying. Moreover, the properties of five different samples were characterized by N_2 adsorption isotherm, SEM/EDS, XPS, and FTIR. The results showed that the maximum PH_3 equilibrium adsorption capacity was 595.56 mg/g. The MWAC had an energetically heterogeneous surface due to values of isosteric heat of adsorption ranging from 43 to 90 kJ/mol. The regeneration method provided an effective way for both adsorption species recycling and exhausted carbon regeneration. The high removal efficiency and big equilibrium adsorption capacity for PH_3 adsorption on the MWAC were related to its large surface area and high oxidation activity in PH_3 adsorption-oxidation to H_3 PO_4 and P_2 O_5. Furthermore, a possible PH_3 adsorption mechanism was proposed.
基金Project supported by the Key Program of National High Technology Research and Development Program of China (863 Program) (2008AA062602)the Young and Middle-aged Academic and Technical Back-up Personnel Program of Yunnan Province (2007PY01-10)the Analysis and Measurement Foundation of Kunming University of Science & Technology
文摘A series of copper-based activated carbon (AC) adsorbents were prepared in order to investigate the effect of Zn, Ce addition on Cu-based AC adsorbent for phosphine (PH3) adsorption removal from yellow phosphorous tail gas. N2 adsorption isotherm and X-ray diffrac-tion (XRD) results suggested that the addition of Zn could increase the adsorbent ultramicropores, decrease the adsorbent supermicropores and the adsorbent average pore diameter. Therefore it enhanced the PH3 adsorption capacity. Appropriate amoun...
基金Project(2017YFC0210500)supported by the National Key Technology R&D Program of ChinaProject(2017ACA092)supported by the Major Projects of Technical Innovation in Hubei Province,China
文摘The absorbent composing of Bayer red mud and water was prepared and applied to removing SO2 from flue gas.Effects of the ratio of liquid to solid(L/S),the absorption temperature,the inlet SO2 concentration,the O2 concentration,SO4^2-and other different components of Bayer red mud on desulfurization were conducted.The mechanism of flue gas desulfurization was also established.The results indicated that L/S was the prominent factor,followed by the inlet SO2 concentration and the temperature was the least among them.The optimum condition was as follows:L/S,the temperature and the SO2 concentration were 20:1,25℃and 1000 mg/m^3,respectively,under the gas flow of 1.5 L/min.The desulfurization efficiency was not significantly influenced when O2 concentration was above 7%.The accumulation of SO4^2-inhibited the desulfurization efficiency.The alkali absorption and metal ions liquid catalytic oxidation were involved in the process,which accounted for 98.61%.
基金supported by the Ministry of Environmental Protection,Public Welfare Project(Contract No 201109034)the National Natural Science Foundation(U1137603)
文摘In this work, a series of coal-based active carbon (CAC) catalysts loaded by A1203 were prepared by sol-gel method and used for the simulta- neous catalytic hydrolysis of carbonyl sulfide (COS) and carbon disulfide (CS2) at relatively low temperatures of 30-70 ℃. The influences of calcinations temperatures and operation conditions such as: reaction temperature, 02 concentration, gas hourly space velocity (GHSV) and relative humidity (RH) were also discussed respectively. The results showed that catalysts with 5.0 wt% A1203 calcined at 300 ℃ had supe- rior activity for the simultaneous catalytic hydrolysis of COS and CS2. When the reaction temperature was above 50 ℃, catalytic hydrolysis activity of COS could be enhanced but that of CS2 was inhibited. Too high RH could make the catalytic hydrolysis activities of COS and CS2 decrease. A small amount of 02 introduction could enhance the simultaneous catalytic hydrolysis activities of COS and CS2.
基金the financial supports of the National Natural Science Foundation of China(No.U1402233)the High-level Scientific Research Foundation for Talent Introduction of Kunming University of Science and Technology(No.10978172)。
文摘Pyrite is the most abundant sulfide semiconductor mineral with excellent optical properties.However,few reports have investigated its photocatalytic activity because of the low photogenerated carrier separation efficiency.In this work,a Z-scheme FeS_(2)/Fe_(2)O_(3)composite photocatalyst was fabricated in situ via structural transformation of pyrite through heat treatment.A remarkably enhanced photocatalytic performance was observed over the FeS_(2)/Fe_(2)O_(3)composite photocatalyst.Compared with the pristine pyrite,the degradation efficiency of carbamazepine(CBZ)reached 65%at the added hexavalent chromium(Cr(Ⅵ))concentration of 20 mg/L and the Cr(Ⅵ)was nearly completely reduced in the mixed system using FeS_(2)/Fe_(2)O_(3)within 30 min under simulated solar light irradiation.The enhanced photocatalytic activity can be attributed to the efficient separation and transfer of photogenerated carriers in the FeS_(2)/Fe_(2)O_(3)composite photocatalyst.This facilitated the generation of·OH,hole(h^(+))and·O_(2)^(-)species,which participated in the photocatalytic reaction with CBZ.Based on the measurement of the active species and electric properties,a Z-scheme electron transfer pathway was proposed for the FeS_(2)/Fe_(2)O_(3)composite photocatalyst.This work broadens the application potential of pyrite in environmental remediation.
基金the Natural Science Foundation of the Department of Education, Guangdong Province, China (No. 02025).
文摘A new method for analysis of trace mercury in water samples was developed, based on the combination of preconcentration/separation using dithizone-modified nanometer titanium dioxide (TiO2) as a solid phase extractant and determination by cold vapor atomic adsorption spectrometry (CVAAS). Dithizone was dissolved with alcohol and loaded on the surface of nano-sized TiO2 powders by stirring. The static adsorption behavior of Hg^2+on the dithizone-modified nanoparficles was investigated in detail. It was found that excellent adsorption ratio for Hg^2+ could be obtained in the pH range of 7-8 with an oscillation time of 15 rain, and a 5 mL of 3.5 mol·L^-1 HCI solution could quantitatively elute Hg^2+ from nanometer TiO2 powder. Common coexisting ions caused no obvious influence on the determination of mercury. The mechanisms for the adsorption and desorption were discussed. The detection limit (30) for Hg^2+ was calculated to be 5 ng·L^-1. The proposed method was applied to the determination of Hg^2+ in a mineral water sample and a Zhujiang River water sample. By the standard addition method, the average recoveries were found to be 94.4%-108.3% with RSD (n = 5) of 2.9%-3.5%.
基金supported by the National Key R&D Program of China (No.2018YFC0213400)the National Natural Science Foundation of China (Nos.51968034,41807373,21667015 and51708266)the Science and Technology Program of Yunnan province (No.2019FB069)。
文摘The sol–gel method was used to synthesize a series of metal oxides-supported activated carbon fiber (ACF) and the simultaneous catalytic hydrolysis activity of carbonyl sulfide (COS)and carbon disulfide (CS2) at relatively low temperatures of 60°C was tested.The effects of preparation conditions on the catalyst properties were investigated,including the kinds and amount of metal oxides and calcination temperatures.The activity tests indicated that catalysts with 5 wt.%Ni after calcining at 400°C (Ni(5)/ACF(400)) had the best performance for the simultaneous catalytic hydrolysis of COS and CS2.The surface and structure properties of prepared ACF were characterized by scanning electron microscope-energy disperse spectroscopy (SEM-EDS),Brunauer–Emmett–Teller (BET),X-ray diffraction (XRD),carbon dioxidetemperature programmed desorption (CO2-TPD) and diffuse reflectance Fourier transform infrared reflection (DRFTIR).And the metal cation defects were researched by electron paramagnetic resonance (EPR) method.The characterization results showed that the supporting of Ni on the ACF made the ACF catalyst show alkaline and increased the specific surface area and the number of micropores,then improved catalytic hydrolysis activity.The DRFTIR results revealed that-OH species could facilitate the hydrolysis of COS and CS2;-COO and-C–O species could facilitate the oxidation of catalytic hydrolysate H2S.And the EPR results showed that high calcination temperature conditions provide more active reaction center for the COS and CS2 adsorption.