Enhanced silicate weathering(ESW)is a geoengineering method aimed at accelerating carbon dioxide(CO_(2))removal(CDR)from atmosphere by increasing the weathering flux of silicate rocks and minerals.It has emerged as a ...Enhanced silicate weathering(ESW)is a geoengineering method aimed at accelerating carbon dioxide(CO_(2))removal(CDR)from atmosphere by increasing the weathering flux of silicate rocks and minerals.It has emerged as a promising strategy for CDR.Theoretical studies underscore ESW’s substantial potential for CDR and its diverse benefits for crops when applied to croplands.However,the well-known significant discrepancies in silicate weathering rates between laboratory and field conditions introduce uncertainty in CDR through ESW.By compiling data from recent literature,we calculated and compared CDR efficiency(t CO_(2)t^(-1)_(silicate)ha^(-1)y^(-1))observed in mesocosm experiments and field trials.The findings indicate that CDR efficiencies in field trials are comparable to or exceeding that observed in mesocosm experiments by 1-3 orders of magnitude,particularly evident with wollastonite application.The hierarchy of CDR efficiency among silicates suitable for ESW is ranked as follows:olivine≥wollastonite>basalt>albite≥anorthite.We suggest the potential role of biota,especially fungi,in contributing to higher CDR efficiencies observed in field trials compared to mesocosm experiments.We further emphasize introducing fungi known for their effectiveness in silicate weathering could potentially enhance CDR efficiency through ESW in croplands.But before implementing fungal-facilitated ESW,three key questions need addressing:(i)How does the community of introduced fungi evolve over time?(ii)What is the long-term trajectory of CDR efficiency following fungal introduction?and(iii)Could fungal introduction lead to organic matter oxidation,resulting in elevated CO_(2)emissions?These investigations are crucial for optimizing the efficiency and sustainability of fungal-facilitated ESW strategy.展开更多
Objective:To analyze the effect of Shiwei Powder combined with stone composition analysis on stone removal efficiency and complication rates after ureteroscopic holmium laser lithotripsy(FURL).Methods:Ninety six patie...Objective:To analyze the effect of Shiwei Powder combined with stone composition analysis on stone removal efficiency and complication rates after ureteroscopic holmium laser lithotripsy(FURL).Methods:Ninety six patients with FURL admitted to the hospital from March 2023 to March 2025 were selected and randomly divided into two groups.The observation group was treated with FURL combined with Shiwei Powder,while the control group was treated with FURL monotherapy.Based on the stone composition of the two groups,the stone removal efficiency,complication rates,recurrence rates,TCM syndrome scores,and inflammatory factor levels were compared.Results:The stone removal efficiency of the observation group was higher than that of the control group.The stone composition was mainly calcium oxalate monohydrate and composite stones containing calcium oxalate monohydrate.The incidence of postoperative complications was lower in the observation group than in the control group(P<0.05).After 3–6 months of follow-up,the recurrence rate in the observation group was lower than that in the control group(P<0.05).After treatment,the TCM syndrome scores and inflammatory factor levels in the observation group were lower than those in the control group(P<0.05).Conclusion:Based on the results of urinary stone composition analysis,patients treated with Shiwei Powder after FURL have higher stone removal efficiency.The most significant effect is observed in urinary stones composed of calcium oxalate monohydrate and composite stones containing calcium oxalate monohydrate.This treatment can improve stone removal,prevent complications,reduce recurrences,effectively improve disease symptoms,and reduce inflammation.展开更多
Ultra-low emission of nitrogen oxide(NO_(x))is an irreversible trend for the development of waste-to-energy industry.But traditional approaches to remove NO_(x) face significant challenge s,such as low denitration eff...Ultra-low emission of nitrogen oxide(NO_(x))is an irreversible trend for the development of waste-to-energy industry.But traditional approaches to remove NO_(x) face significant challenge s,such as low denitration efficiency,complex denitration system,and high investment and operating cost.Here we put forward a novel polymer non-catalytic reduction(PNCR)technology that utilized a new type of polymer agent to remove NO_(x),and the proposed PNCR technology was applied to the existing waste-to-energy plant to test the denitration performance.The PNCR technology demonstrated excellent denitration performance with a NO_(x) emission concentration of<100 mg/Nm^(3) and high denitration efficiency of>75%at the temperature range of 800-900℃,which showed the application feasibility even on the complex and unstable industrial operating conditions.In addition,PNCR and hybrid polymer/selective non-catalytic reduction(PNCR/SNCR)technology possessed remarkable economic advantages including low investment fee and low operating cost of<10 CNY per ton of municipal solid waste(MSW)compared with selective catalytic reduction(SCR)technology.The excellent denitration performance of PNCR technology forebodes a broad industrial application prospect in the field of flue gas cleaning for waste-to-energy plants.展开更多
Ketoprofen(KET),as a non-steroidal anti-inflammatory drug frequently detected in aqueous environments,is a threat to human health due to its accumulation and low biodegradability,which requires the transformation and ...Ketoprofen(KET),as a non-steroidal anti-inflammatory drug frequently detected in aqueous environments,is a threat to human health due to its accumulation and low biodegradability,which requires the transformation and degradation of KET in aqueous environments.In this paper,the reaction process of ozone-initiated KET degradation in water was investigated using density functional theory(DFT)method at the M06-2X/6-311++g(3df,2p)//M06-2X/6-31+g(d,p)level.The detailed reaction path of KET ozonation is proposed.The thermodynamic results show that ozone-initiated KET degradation is feasible.Under ultraviolet irradiation,the reaction of ozone with water can also produce OH radicals(HO·)that can react with KET.The degradation reaction of KET caused by HO·was further studied.The kinetic calculation illustrates that the reaction rate(1.99×10-1(mol/L)^(-1)sec^(-1))of KET ozonation is relatively slow,but the reaction rate of HO·reaction is relatively high,which can further improve the degradation efficiency.On this basis,the effects of pollutant concentration,ozone concentration,natural organic matter,and pH value on degradation efficiency under UV/O3 process were analyzed.The ozonolysis reaction of KET is not sensitive to pH and is basically unaffected.Finally,the toxicity prediction of oxidation compounds produced by degradation reaction indicates that most of the degradation products are harmless,and a few products containing benzene rings are still toxic and have to be concerned.This study serves as a theoretical basis for analyzing the migration and transformation process of anti-inflammatory compounds in the water environment.展开更多
Photocatalytic NO removal is regarded as an attractive strategy to reduce NO pollution in the air,but the lack of efficient and stable catalysts impedes its applications.Herein,we report on developing Ti_(3)C_(2)suppo...Photocatalytic NO removal is regarded as an attractive strategy to reduce NO pollution in the air,but the lack of efficient and stable catalysts impedes its applications.Herein,we report on developing Ti_(3)C_(2)supported on N-defective g-C_(3)N_(5)nanosheets(CN_(X)/TC)as an efficient photocatalyst toward NO removal.It is noteworthy that TC changed from crystal structure to amorphous structure during the photocatalytic process.Due to the existence of N vacancies and amorphous structure,the designed CN_(X)/TC composites possess abundant unsaturated sites for adsorption and activation of O_(2)and NO,thus facilitating the removal of NO and inhibiting the generation of NO_(2).The as-prepared CN_(X)/TC-2%shows the best activity for NO removal and inhibits toxic NO_(2)generation.The removal rate of NO is up to 48%,which is about 2 and 4 times higher than those of pure CN_(X)and CN,respectively.In addition,the in situ diffused reflection Fourier transform infrared spectroscopy was used to investigate the NO transfer pathway during the photocatalytic process.This work might provide new insights into the catalytic role of N-defect and amorphous,inspiring the rational design of catalysts in the field of photocatalytic NO removal.展开更多
Advanced oxidation processes are promising for degradation of the highly chemical stability and refractory methylisothiazolinone(MIT) bactericides in relevant industrial wastewater.In order to assemble a low cost and ...Advanced oxidation processes are promising for degradation of the highly chemical stability and refractory methylisothiazolinone(MIT) bactericides in relevant industrial wastewater.In order to assemble a low cost and high performance electrochemical oxidation system for wastewater treatment,granular active carbon(GAC) was decorated by doping Ce,Sn,Sb to synthesize Sn-Sb-Ce/GAC using sol-gel method as particle electrode filled into a three-dimensional(3D) electrochemical reactor.Scanning electron microscopy(SEM),energy-dispersive spectroscopy(EDS) and X-ray diffraction(XRD) experiments revealed that the Sn-Sb-Ce/GAC particle electrode crystal particles were compact and uniform,and the surface structure was improved.The ten cyclic experiments indicated that the Sn-Sb-Ce/GAC particle electrode had high stability and low dissolution of the loaded active substance.The degradation mechanism of MIT was studied under the optimal working conditions of 3D electrode system with GAC of 5 g/L,current density of 20 mA/cm^(2),initial pH 5,electrolyte concentration of Na_(2)SO_(4)0.02 mol/L and reaction time of 120 min.The indirect electrochemical degradation of MIT was dominated by active substance pathway that active chlorine rather than free radicals(·OH) played the main role.Comparing with conventional two-dimensional(2D) electrode system,the 3D electrochemical system has larger active electrode area,higher treatment efficiency and lower energy consumption than the former.The 3D electrochemical system could remove 96.5% of MIT from the actual high-salt reverse osmosis concentrate wastewater in 30 min.It has a certain removal effect on UV_(254)in wastewater,but has a better removal effect on fluorescent substances.This study proposed a new strategy to develop transition metal and rare earth metal particle electrodes using carbon-based materials for high efficient electrocatalytic oxidation in the electrochemical treatment system.展开更多
The discharge of micro-polluted water from sources such as agricultural runoff,urban stormwater,and treated effluents presents significant challenges to aquatic ecosystems.Constructed wetlands(CWs)have gained recog-ni...The discharge of micro-polluted water from sources such as agricultural runoff,urban stormwater,and treated effluents presents significant challenges to aquatic ecosystems.Constructed wetlands(CWs)have gained recog-nition as an eco-friendly solution for removing pollutants from various wastewater sources and are increasingly applied for micro-polluted water treatment.By reviewing 78 full-scale CW studies from Web of Science,it is summarized that the ranges of ammonium nitrogen(NH4+-N)concentrations in runoff,wastewater treatment plant effluent and polluted river were 0.1–6.6,0.3–12.3,and 0.2–41.1 mg/L,respectively.The ranges of ni-trate nitrogen concentrations were 0.2–14.2,0–5.7,and 0–2.6 mg/L,respectively.Removal efficiencies of CWs for micro-polluted water varied by CW types.The total nitrogen removal efficiencies for subsurface-flow CWs,free-water surface-flow CWs,and hybrid CWs ranged from 27.4%to 66.5%,16.8%to 89.8%,and 19.4%to 88.2%,respectively.The NH4+-N removal efficiencies ranged from 34.2%to 73.6%,38.4%to 89.4%and 13.5%to 94.2%,respectively.Additionally,other factors influencing contaminant removal efficiency such as hydraulic retention time,vegetation types,redox micro-environment and influent water quality were evaluated.Based on these findings,two strategies for improving the purification performance of CWs were proposed:the selection of incorporating electron donor substrates and the optimization of operation parameters.This paper serves as a synthesis of information to guide future research and full-scale CW applications in micro-polluted water treatment.展开更多
Laser-induced aerosols,predominantly submicron in size,pose significant environmental and health risks during the decommissioning of nuclear reactors.This study experimentally investigated the removal of laser-generat...Laser-induced aerosols,predominantly submicron in size,pose significant environmental and health risks during the decommissioning of nuclear reactors.This study experimentally investigated the removal of laser-generated aerosol particles using a water spray system integrated with an innovative system for pre-injecting electrically charged mist in our facility.To simulate aerosol generation in reactor decommissioning,a high-power laser was used to irradiate various materials(including stainless steel,carbon steel,and concrete),generating aerosol particles that were agglomerated with injected water mist and subsequently scavenged by water spray.Experimental results demonstrate enhanced aerosol removal via aerosol-mist agglomeration,with charged mist significantly improving particle capture by increasing wettability and size.The average improvements for the stainless steel,carbon steel,and concrete were 40%,44%,and 21%,respectively.The results of experiments using charged mist with different polarities(both positive and negative)and different surface coatings reveal that the dominant polarity of aerosols varies with the irradiated materials,influenced by their crystal structure and electron emission properties.Notably,surface coatings such as ZrO_(2)and CeO_(2)were found to possibly alter aerosol charging characteristics,thereby affecting aerosol removal efficiency with charged mist configurations.The innovative aerosol-mist agglomeration approach shows promise in mitigating radiation exposure,ensuring environmental safety,and reducing contaminated water during reactor dismantling.This study contributes critical knowledge for the development of advanced aerosol management strategies for nuclear reactor decommissioning.The understanding obtained in this work is also expected to be useful for various environmental and chemical engineering applications such as gas decontamination,air purification,and pollution control.展开更多
A nonfused ring electron acceptor(NFREA),designated as TT-Ph-C6,has been synthesized with the aim of enhancing the power conversion efficiency(PCE)of organic solar cells(OSCs).By integrating asymmetric phenylalkylamin...A nonfused ring electron acceptor(NFREA),designated as TT-Ph-C6,has been synthesized with the aim of enhancing the power conversion efficiency(PCE)of organic solar cells(OSCs).By integrating asymmetric phenylalkylamino side groups,TT-Ph-C6 demonstrates excellent solubility and its crystal structure exhibits compact packing structures with a three-dimensional molecular stacking network.These structural attributes markedly promote exciton diffusion and charge carrier mobility,particularly advantageous for the fabrication of thick-film devices.TT-Ph-C6-based devices have attained a PCE of 18.01%at a film thickness of 100 nm,and even at a film thickness of 300 nm,the PCE remains at 14.64%,surpassing that of devices based on 2BTh-2F.These remarkable properties position TT-Ph-C6 as a highly promising NFREA material for boosting the efficiency of OSCs.展开更多
A high-sensitivity,low-noise single photon avalanche diode(SPAD)detector was presented based on a 180 nm BCD process.The proposed device utilizes a p-implant layer/high-voltage n-well(HVNW)junction to form a deep aval...A high-sensitivity,low-noise single photon avalanche diode(SPAD)detector was presented based on a 180 nm BCD process.The proposed device utilizes a p-implant layer/high-voltage n-well(HVNW)junction to form a deep avalanche multiplication region for near-infrared(NIR)sensitivity enhancement.By optimizing the device size and electric field of the guard ring,the fill factor(FF)is significantly improved,further increasing photon detection efficiency(PDE).To solve the dark noise caused by the increasing active diameter,a field polysilicon gate structure connected to the p+anode was investigated,effectively suppressing dark count noise by 76.6%.It is experimentally shown that when the active diameter increases from 5 to 10μm,the FF is significantly improved from 20.7%to 39.1%,and thus the peak PDE also rises from 13.3%to 25.8%.At an excess bias voltage of 5 V,a NIR photon detection probability(PDP)of 6.8%at 905 nm,a dark count rate(DCR)of 2.12 cps/μm^(2),an afterpulsing probability(AP)of 1.2%,and a timing jitter of 216 ps are achieved,demonstrating excellent single photon detection performance.展开更多
To master theoretical calculation for dust removal efficiency of high pressure atomization in an underground coal mine, the corresponding atomization characteristics and dust removal efficiency were both comprehensive...To master theoretical calculation for dust removal efficiency of high pressure atomization in an underground coal mine, the corresponding atomization characteristics and dust removal efficiency were both comprehensively studied in theory by virtue of related theories of hydromechanics and aerosol.According to actual measurements of flow coefficients and atomization angles of X-type swirl nozzle,computational formula was derived for atomized particle sizes of such a nozzle in conjunction with relevant empirical equation. Moreover, a mathematical model for applying high pressure atomization to dust removal in underground coal mine was also established to deduce theoretical computation formula of fractional efficiency. Then, Matlab was adopted to portray the relation curve between fractional efficiency and influence factors. In addition, a theoretical formula was also set up for removal efficiency of respirable dust and total coal dust based on dust size and frequency distribution equations. In the end,impacts of dust characteristic parameters on various dust removal efficiencies were analyzed.展开更多
Using total suspended solid (TSS) removal efficiency and hydraulic retention time (HRT) as design parameters a design guideline of a settling basin in a constructed wetland (CW) was suggested; as well as managem...Using total suspended solid (TSS) removal efficiency and hydraulic retention time (HRT) as design parameters a design guideline of a settling basin in a constructed wetland (CW) was suggested; as well as management of sediment and particle in the settling basin. The CW was desiEned to treat the piggery wastewater effluent from a wastewater treatment plant during dry days and stonnwater runoff from the surrounding paved area during wet days. The first settling basin (FSB) in the CVV was theoretically designed with a total storage volume (TSV) of 453 ms and HRT of 5.5 hr. The amount of sediment and particles settled at the FSB was high due to the sedimentation and interception of plants in the CVV. Dredging of sediments was performed when the retention rate at the FSB decreased to approximately 80%. Findings showed that the mean flow rate was 21.8 m3/hr less than the designed flow rate of 82.8 m3/hr indicating that the FSB was oversize and operated with longer HRT (20.7 hr) compared to the design HRT. An empirical model to estimate the length of the settling basin in the CW was developed as a function of HRT and desired TSS removal efficiency. Using the minimum tolerable TSS removal efficiency of 30%, the length of the FSB was estimated to be 31.2 m with 11.8 hr HRT.展开更多
The nitrate nitrogen removal efficiency of iron-carbon micro-electrolysis system was discussed in treating pharmaceutical wastewater with high nitrogen and refractory organic concentration. The results show that the g...The nitrate nitrogen removal efficiency of iron-carbon micro-electrolysis system was discussed in treating pharmaceutical wastewater with high nitrogen and refractory organic concentration. The results show that the granularity of fillings,pH,volume ratios of iron-carbon and gas-water,and HRT. have significant effects on the nitrogen removal efficiency of iron-carbon micro-electrolysis system. The iron-carbon micro-electrolysis system has a good removal efficiency of pharmaceutical wastewater with high nitrogen and refractory organic concentration when the influent TN,NH4+-N,NO3--N and BOD5/CODCr are 823 mg/L,30 mg/L,793 mg/L and 0.1,respectively,at the granularity of iron and carbon 0.425 mm,pH 3,iron-carbon ratio 3,gas-water ratio 5,HRT 1.5 h,and the removal rates of TN,NH4+-N and NO3--N achieve 51.5%,70% and 50.94%,respectively.展开更多
In this paper, an experimental study on SO2 removal by nanosecond rising edge pulse dielectric barrier discharge (DBD) plasma, generated by multi-needle-to-plane electrodes, is carried out. The mechanism of the effe...In this paper, an experimental study on SO2 removal by nanosecond rising edge pulse dielectric barrier discharge (DBD) plasma, generated by multi-needle-to-plane electrodes, is carried out. The mechanism of the effect of various factors, such as gap size between dielectric barrier and discharge needles, environmental humidity, and inlet speed of gas flow upon the removal efficiency of air purification is analyzed. The studies show that SOs removal efficiency improves with the increase in the gap size between dielectric barrier and discharge needles in the case of a fixed space between two electrodes, and also improves with the increase in the environmental humidity. For a mixed gas with a fixed concentration, there is an optimal inlet speed of gas flow, which leads to the best removal efficiency.展开更多
In order to reduce the amount of NO_3^-–N generated by the Anammox process, and alleviate the competition between denitrification and Anammox for NO_2^-–N in a single reactor, the preference of S^0 for reacting with...In order to reduce the amount of NO_3^-–N generated by the Anammox process, and alleviate the competition between denitrification and Anammox for NO_2^-–N in a single reactor, the preference of S^0 for reacting with coexisting NO_2^-–N and NO_3^-–N in the sulfur autotrophic denitrifying(SADN) process and the coupling effect of short-cut SADN and the Anammox process were studied. The results showed that S^0 preferentially reacted with NO_3^-to produce NO_2^-–N, and then reacted with NO_2^-–N when NO_3^-–N was insufficient, which could effectively alleviate the competition between SADN bacteria(SADNB) and Anammox bacteria(An AOB) for NO_2^-–N. After 170 days of operation, coupling between short-cut S^0-SADN and the Anammox process was first successfully achieved. SADNB converted the NO_3^-–N generated by the Anammox process into NO_2^-–N, which was once again available to An AOB. The total nitrogen removal efficiency eventually stabilized at over 95%, and the effluent NO_3^-–N was controlled within 10 mg/L, when high NH_4^+–N wastewater was treated by the Anammox process. Microbial community analysis further showed that Candidatus Brocadia and Thiobacillus were the functional microorganisms for An AOB and SADNB.展开更多
A heteropore covalent organic framework(COF) integrating tetraphenylethene skeleton and catechol segment is designed and synthesized.It exhibits extremely high stability in water under different pH conditions,which ma...A heteropore covalent organic framework(COF) integrating tetraphenylethene skeleton and catechol segment is designed and synthesized.It exhibits extremely high stability in water under different pH conditions,which makes it an excellent material for adsorptive removal of Cd(Ⅱ) from aqueous solutions with very fast adsorption kinetics,high uptake capacity,and good recyclability.展开更多
Large quantities of sludge are produced during water treatment processes. Recently, sludge has been treated as waste and disposed of in landfills, which increases the environmental burdens and the operational cost. Th...Large quantities of sludge are produced during water treatment processes. Recently, sludge has been treated as waste and disposed of in landfills, which increases the environmental burdens and the operational cost. Therefore, sludge reuse has become a significant environmental issue. In this study, adsorption of copper ions (Cu^2+) onto calcined sludge was investigated under various operational conditions (with varying temperature, Cu^2+ initial concentration, pH, and sludge dosage). The prepared sludge material was characterized with transmission electron microscopy (TEM), X-ray diffraction (XRD), dynamic light scattering (DLS), and Brunauer-Emmett-Teller (BET) surface area. The sorption capacity of sludge was directly proportional to the initial Cu^2+ concentration and inversely proportional to the sludge dosage. The optimum operational pH and solution temperature were 6.6 and 80℃, respectively. The experimental results followed a Langmuir isotherm and pseudo-first-order adsorption kinetics. Thermodynamic parameters such as activation energy, change in free energy, enthalpy, and entropy were calculated. Thermodynamic analyses indicated that the sorption of copper ions onto the calcined sludge was driven by a physical adsorption process. The prepared sludge was proven to be an excellent adsorbent material for the removal of Cu^2+ from an aqueous solution under optimum conditions.展开更多
Iron-manganese composited oxide(FeMnO) was prepared with potassium permanganate and ferrous salt. Interface performance, charge property and structure topography of the FeMnO were investigated. Coagulation efficienc...Iron-manganese composited oxide(FeMnO) was prepared with potassium permanganate and ferrous salt. Interface performance, charge property and structure topography of the FeMnO were investigated. Coagulation efficiency and pollution removal mechanism of the FeMnO were approached. Results show that the main compositions of the FeMnO are δ-manganese dioxide and ferric hydroxide. The specific surface area is about 146.22 m^2/g. The FeMnO contains rich hydroxyl with extremely strong adsorption action and chemical adsorption activity. The zero charge point of the oxide in pure water is about 8.0 of pH value. Under neutral pH value conditions, the FeMnO particle surface carried positive charges. The FeMnO particles are quasi-spherical micro-particles with irregular sizes adjoined each other to form net construction. Phosphorus removal efficiency of the FeMnO is remarkable, the total dissoluble phosphorus of settled water can be reduced below detecting level(0.3 μtg/L) at a FeMnO dosage of 6 mg/L, and total phosphorus below detecting level at a FeMnO dosage of 10 mg/L, for water samples containing total phos- phorus of 1281.70 μg/L and total dissoluble phosphorus of 1187.91 μtg/L. The mechanism of effective coagulation for phosphorus removal is combined results of multiple actions of adsorption, charge neutralization, adsorption/bridging and so on.展开更多
This paper describes the preparation of a membrane of polyacrylonitrile(PAN)and its corresponding membrane coated with polyaniline(PANI)for the adsorption of heavy metal ions.Scanning electron microscopy micrographs r...This paper describes the preparation of a membrane of polyacrylonitrile(PAN)and its corresponding membrane coated with polyaniline(PANI)for the adsorption of heavy metal ions.Scanning electron microscopy micrographs revealed that all the membranes exhibited nanofibrous morphology.The prepared membranes were characterized by Fourier transform infrared spectroscopy(FTIR).The prepared membranes were used as an adsorbent for hazardous heavy metal ions Pb^(2+) and Cr_(2)O^(2-)_(7).The adsorption capacity and the removal efficiency of the membranes were examined as function of the initial adsorbate concentration and pH of the medium.Coated membranes with PANI showed better adsorption performance and their direct current(DC)conductivities were correlated to heavy metal ion concentrations.Adsorption isotherms were also performed,and the adsorption process was tested according to the Langmuir and Freundlich models.The regeneration and reuse of the prepared membranes to re-adsorb heavy metal ions were also investigated.The enhancement in adsorption performance and reusability of PANI-coated membranes in comparison with non-coated ones is fully discussed.The results show that the maximum adsorption capacities of lead and chromate ions on the PANI-coated membranes are 290.12 and 1202.53 mg/g,respectively.展开更多
Based onmultiphase flowtheory and capillary mechanics,the dimensionless bond number expression of the influence of string grille wire spacing on droplet spreading is derived.Taking a liquid film formed by spreading dr...Based onmultiphase flowtheory and capillary mechanics,the dimensionless bond number expression of the influence of string grille wire spacing on droplet spreading is derived.Taking a liquid film formed by spreading droplets based on Kelvin correlation,the Young-Laplace equation,and the Hagen-Poiseuille law,an equation for calculating the thickness and height of the liquid film is established with temperature,relative humidity and molar volume of liquid phase as independent variables.According to the theory of string grille filtration and dust removal,a dust removal efficiency calculation model covering the wet string grille wire group is constructed based on the liquid film thickness,height,wire diameter,water film area,and vortex shedding frequency.Finally,a theoretical analysis of the influence of water film area on the efficiency of wet string grille dust removal is carried out based on the spray pressure and the ratio of string grille wire distance to wire diameter.It is found that the effect of spray pressure on water film area and dust removal efficiency is more significant than the string grille wire distance diameter ratio.Moreover,the optimized combination of wet string grille wire distance diameter ratio 0.84,wind speed 3m/s and spray pressure 0.8 MPa is found,which could provide an important reference for engineering applications.展开更多
基金funded by the National Natural Science Foundation of China(Nos.42173059 and 41991322)。
文摘Enhanced silicate weathering(ESW)is a geoengineering method aimed at accelerating carbon dioxide(CO_(2))removal(CDR)from atmosphere by increasing the weathering flux of silicate rocks and minerals.It has emerged as a promising strategy for CDR.Theoretical studies underscore ESW’s substantial potential for CDR and its diverse benefits for crops when applied to croplands.However,the well-known significant discrepancies in silicate weathering rates between laboratory and field conditions introduce uncertainty in CDR through ESW.By compiling data from recent literature,we calculated and compared CDR efficiency(t CO_(2)t^(-1)_(silicate)ha^(-1)y^(-1))observed in mesocosm experiments and field trials.The findings indicate that CDR efficiencies in field trials are comparable to or exceeding that observed in mesocosm experiments by 1-3 orders of magnitude,particularly evident with wollastonite application.The hierarchy of CDR efficiency among silicates suitable for ESW is ranked as follows:olivine≥wollastonite>basalt>albite≥anorthite.We suggest the potential role of biota,especially fungi,in contributing to higher CDR efficiencies observed in field trials compared to mesocosm experiments.We further emphasize introducing fungi known for their effectiveness in silicate weathering could potentially enhance CDR efficiency through ESW in croplands.But before implementing fungal-facilitated ESW,three key questions need addressing:(i)How does the community of introduced fungi evolve over time?(ii)What is the long-term trajectory of CDR efficiency following fungal introduction?and(iii)Could fungal introduction lead to organic matter oxidation,resulting in elevated CO_(2)emissions?These investigations are crucial for optimizing the efficiency and sustainability of fungal-facilitated ESW strategy.
文摘Objective:To analyze the effect of Shiwei Powder combined with stone composition analysis on stone removal efficiency and complication rates after ureteroscopic holmium laser lithotripsy(FURL).Methods:Ninety six patients with FURL admitted to the hospital from March 2023 to March 2025 were selected and randomly divided into two groups.The observation group was treated with FURL combined with Shiwei Powder,while the control group was treated with FURL monotherapy.Based on the stone composition of the two groups,the stone removal efficiency,complication rates,recurrence rates,TCM syndrome scores,and inflammatory factor levels were compared.Results:The stone removal efficiency of the observation group was higher than that of the control group.The stone composition was mainly calcium oxalate monohydrate and composite stones containing calcium oxalate monohydrate.The incidence of postoperative complications was lower in the observation group than in the control group(P<0.05).After 3–6 months of follow-up,the recurrence rate in the observation group was lower than that in the control group(P<0.05).After treatment,the TCM syndrome scores and inflammatory factor levels in the observation group were lower than those in the control group(P<0.05).Conclusion:Based on the results of urinary stone composition analysis,patients treated with Shiwei Powder after FURL have higher stone removal efficiency.The most significant effect is observed in urinary stones composed of calcium oxalate monohydrate and composite stones containing calcium oxalate monohydrate.This treatment can improve stone removal,prevent complications,reduce recurrences,effectively improve disease symptoms,and reduce inflammation.
基金supported by the National Natural Science Foundation of China(No.92367107)。
文摘Ultra-low emission of nitrogen oxide(NO_(x))is an irreversible trend for the development of waste-to-energy industry.But traditional approaches to remove NO_(x) face significant challenge s,such as low denitration efficiency,complex denitration system,and high investment and operating cost.Here we put forward a novel polymer non-catalytic reduction(PNCR)technology that utilized a new type of polymer agent to remove NO_(x),and the proposed PNCR technology was applied to the existing waste-to-energy plant to test the denitration performance.The PNCR technology demonstrated excellent denitration performance with a NO_(x) emission concentration of<100 mg/Nm^(3) and high denitration efficiency of>75%at the temperature range of 800-900℃,which showed the application feasibility even on the complex and unstable industrial operating conditions.In addition,PNCR and hybrid polymer/selective non-catalytic reduction(PNCR/SNCR)technology possessed remarkable economic advantages including low investment fee and low operating cost of<10 CNY per ton of municipal solid waste(MSW)compared with selective catalytic reduction(SCR)technology.The excellent denitration performance of PNCR technology forebodes a broad industrial application prospect in the field of flue gas cleaning for waste-to-energy plants.
基金supported by the National Nature Science Foundation of China(Nos.21777087 and 22276109)the Natural Science Basic Research Fund of Shaanxi Province(No.2023-JC-QN-0099)+1 种基金the Fundamental Research Funds for the Central Universities,CHD(No.300102352101)the Innovative Research Team for Science and Technology of Shaanxi Province(No.2022TD-04).
文摘Ketoprofen(KET),as a non-steroidal anti-inflammatory drug frequently detected in aqueous environments,is a threat to human health due to its accumulation and low biodegradability,which requires the transformation and degradation of KET in aqueous environments.In this paper,the reaction process of ozone-initiated KET degradation in water was investigated using density functional theory(DFT)method at the M06-2X/6-311++g(3df,2p)//M06-2X/6-31+g(d,p)level.The detailed reaction path of KET ozonation is proposed.The thermodynamic results show that ozone-initiated KET degradation is feasible.Under ultraviolet irradiation,the reaction of ozone with water can also produce OH radicals(HO·)that can react with KET.The degradation reaction of KET caused by HO·was further studied.The kinetic calculation illustrates that the reaction rate(1.99×10-1(mol/L)^(-1)sec^(-1))of KET ozonation is relatively slow,but the reaction rate of HO·reaction is relatively high,which can further improve the degradation efficiency.On this basis,the effects of pollutant concentration,ozone concentration,natural organic matter,and pH value on degradation efficiency under UV/O3 process were analyzed.The ozonolysis reaction of KET is not sensitive to pH and is basically unaffected.Finally,the toxicity prediction of oxidation compounds produced by degradation reaction indicates that most of the degradation products are harmless,and a few products containing benzene rings are still toxic and have to be concerned.This study serves as a theoretical basis for analyzing the migration and transformation process of anti-inflammatory compounds in the water environment.
基金the support from the Scientific Research Program Funded by Education Department of Shaanxi Provincial Government(No.23JP011)Guangzhou Fundamental Research Program(No.2023A04J0697)the scientific research startup fund of Shaanxi University of Science and Technology。
文摘Photocatalytic NO removal is regarded as an attractive strategy to reduce NO pollution in the air,but the lack of efficient and stable catalysts impedes its applications.Herein,we report on developing Ti_(3)C_(2)supported on N-defective g-C_(3)N_(5)nanosheets(CN_(X)/TC)as an efficient photocatalyst toward NO removal.It is noteworthy that TC changed from crystal structure to amorphous structure during the photocatalytic process.Due to the existence of N vacancies and amorphous structure,the designed CN_(X)/TC composites possess abundant unsaturated sites for adsorption and activation of O_(2)and NO,thus facilitating the removal of NO and inhibiting the generation of NO_(2).The as-prepared CN_(X)/TC-2%shows the best activity for NO removal and inhibits toxic NO_(2)generation.The removal rate of NO is up to 48%,which is about 2 and 4 times higher than those of pure CN_(X)and CN,respectively.In addition,the in situ diffused reflection Fourier transform infrared spectroscopy was used to investigate the NO transfer pathway during the photocatalytic process.This work might provide new insights into the catalytic role of N-defect and amorphous,inspiring the rational design of catalysts in the field of photocatalytic NO removal.
基金the financial supports from Major Science and Technology project of China Power Engineering Consulting Group Co., Ltd. "Research on Green and digital Intelligent Technology of Sewage Treatment Plant" (No. CEEC2023-ZDYF-09)Technology Innovation Ability Improvement Project of Shandong Province, China (No. 2022TSGC1247)。
文摘Advanced oxidation processes are promising for degradation of the highly chemical stability and refractory methylisothiazolinone(MIT) bactericides in relevant industrial wastewater.In order to assemble a low cost and high performance electrochemical oxidation system for wastewater treatment,granular active carbon(GAC) was decorated by doping Ce,Sn,Sb to synthesize Sn-Sb-Ce/GAC using sol-gel method as particle electrode filled into a three-dimensional(3D) electrochemical reactor.Scanning electron microscopy(SEM),energy-dispersive spectroscopy(EDS) and X-ray diffraction(XRD) experiments revealed that the Sn-Sb-Ce/GAC particle electrode crystal particles were compact and uniform,and the surface structure was improved.The ten cyclic experiments indicated that the Sn-Sb-Ce/GAC particle electrode had high stability and low dissolution of the loaded active substance.The degradation mechanism of MIT was studied under the optimal working conditions of 3D electrode system with GAC of 5 g/L,current density of 20 mA/cm^(2),initial pH 5,electrolyte concentration of Na_(2)SO_(4)0.02 mol/L and reaction time of 120 min.The indirect electrochemical degradation of MIT was dominated by active substance pathway that active chlorine rather than free radicals(·OH) played the main role.Comparing with conventional two-dimensional(2D) electrode system,the 3D electrochemical system has larger active electrode area,higher treatment efficiency and lower energy consumption than the former.The 3D electrochemical system could remove 96.5% of MIT from the actual high-salt reverse osmosis concentrate wastewater in 30 min.It has a certain removal effect on UV_(254)in wastewater,but has a better removal effect on fluorescent substances.This study proposed a new strategy to develop transition metal and rare earth metal particle electrodes using carbon-based materials for high efficient electrocatalytic oxidation in the electrochemical treatment system.
基金supported by the Natural Science Foundation of China(No.52470105)the Young Taishan Scholars Program of Shandong Province(No.358202103017).
文摘The discharge of micro-polluted water from sources such as agricultural runoff,urban stormwater,and treated effluents presents significant challenges to aquatic ecosystems.Constructed wetlands(CWs)have gained recog-nition as an eco-friendly solution for removing pollutants from various wastewater sources and are increasingly applied for micro-polluted water treatment.By reviewing 78 full-scale CW studies from Web of Science,it is summarized that the ranges of ammonium nitrogen(NH4+-N)concentrations in runoff,wastewater treatment plant effluent and polluted river were 0.1–6.6,0.3–12.3,and 0.2–41.1 mg/L,respectively.The ranges of ni-trate nitrogen concentrations were 0.2–14.2,0–5.7,and 0–2.6 mg/L,respectively.Removal efficiencies of CWs for micro-polluted water varied by CW types.The total nitrogen removal efficiencies for subsurface-flow CWs,free-water surface-flow CWs,and hybrid CWs ranged from 27.4%to 66.5%,16.8%to 89.8%,and 19.4%to 88.2%,respectively.The NH4+-N removal efficiencies ranged from 34.2%to 73.6%,38.4%to 89.4%and 13.5%to 94.2%,respectively.Additionally,other factors influencing contaminant removal efficiency such as hydraulic retention time,vegetation types,redox micro-environment and influent water quality were evaluated.Based on these findings,two strategies for improving the purification performance of CWs were proposed:the selection of incorporating electron donor substrates and the optimization of operation parameters.This paper serves as a synthesis of information to guide future research and full-scale CW applications in micro-polluted water treatment.
基金financial support from the Nuclear Energy Science&Technology and Human Resource Development Project of the Japan Atomic Energy Agency/Collaborative Laboratories for Advanced Decommissioning Science(No.R04I034)The author Ruicong Xu appreciates the scholarship(financial support)from the China Scholarship Council(CSC,No.202106380073).
文摘Laser-induced aerosols,predominantly submicron in size,pose significant environmental and health risks during the decommissioning of nuclear reactors.This study experimentally investigated the removal of laser-generated aerosol particles using a water spray system integrated with an innovative system for pre-injecting electrically charged mist in our facility.To simulate aerosol generation in reactor decommissioning,a high-power laser was used to irradiate various materials(including stainless steel,carbon steel,and concrete),generating aerosol particles that were agglomerated with injected water mist and subsequently scavenged by water spray.Experimental results demonstrate enhanced aerosol removal via aerosol-mist agglomeration,with charged mist significantly improving particle capture by increasing wettability and size.The average improvements for the stainless steel,carbon steel,and concrete were 40%,44%,and 21%,respectively.The results of experiments using charged mist with different polarities(both positive and negative)and different surface coatings reveal that the dominant polarity of aerosols varies with the irradiated materials,influenced by their crystal structure and electron emission properties.Notably,surface coatings such as ZrO_(2)and CeO_(2)were found to possibly alter aerosol charging characteristics,thereby affecting aerosol removal efficiency with charged mist configurations.The innovative aerosol-mist agglomeration approach shows promise in mitigating radiation exposure,ensuring environmental safety,and reducing contaminated water during reactor dismantling.This study contributes critical knowledge for the development of advanced aerosol management strategies for nuclear reactor decommissioning.The understanding obtained in this work is also expected to be useful for various environmental and chemical engineering applications such as gas decontamination,air purification,and pollution control.
基金Financial support from the National Natural Science Foundation of China(22375024,21975031,21734009,51933001,22109080,and 52173174)the Natural Science Foundation of Shandong Province(No.ZR2022YQ45)+2 种基金the Taishan Scholars Program(Nos.tstp20221121 and tsqnz20221134)The Beijing Natural Science Foundation(No.2244073)supported by State Key Laboratory of Bio-Fibers and Eco-Textiles(Qingdao University)(RZ2200002821)is acknowledged.
文摘A nonfused ring electron acceptor(NFREA),designated as TT-Ph-C6,has been synthesized with the aim of enhancing the power conversion efficiency(PCE)of organic solar cells(OSCs).By integrating asymmetric phenylalkylamino side groups,TT-Ph-C6 demonstrates excellent solubility and its crystal structure exhibits compact packing structures with a three-dimensional molecular stacking network.These structural attributes markedly promote exciton diffusion and charge carrier mobility,particularly advantageous for the fabrication of thick-film devices.TT-Ph-C6-based devices have attained a PCE of 18.01%at a film thickness of 100 nm,and even at a film thickness of 300 nm,the PCE remains at 14.64%,surpassing that of devices based on 2BTh-2F.These remarkable properties position TT-Ph-C6 as a highly promising NFREA material for boosting the efficiency of OSCs.
基金supported by the National Natural Science Foundation of China under Grant 62171233the Natural Science Foundation of China,Jiangsu Province under Grant BK20241891the Jiangsu Province Graduate Research and Practice Innovation Plan under Grants SJCX24_0313 and KYCX24_1169。
文摘A high-sensitivity,low-noise single photon avalanche diode(SPAD)detector was presented based on a 180 nm BCD process.The proposed device utilizes a p-implant layer/high-voltage n-well(HVNW)junction to form a deep avalanche multiplication region for near-infrared(NIR)sensitivity enhancement.By optimizing the device size and electric field of the guard ring,the fill factor(FF)is significantly improved,further increasing photon detection efficiency(PDE).To solve the dark noise caused by the increasing active diameter,a field polysilicon gate structure connected to the p+anode was investigated,effectively suppressing dark count noise by 76.6%.It is experimentally shown that when the active diameter increases from 5 to 10μm,the FF is significantly improved from 20.7%to 39.1%,and thus the peak PDE also rises from 13.3%to 25.8%.At an excess bias voltage of 5 V,a NIR photon detection probability(PDP)of 6.8%at 905 nm,a dark count rate(DCR)of 2.12 cps/μm^(2),an afterpulsing probability(AP)of 1.2%,and a timing jitter of 216 ps are achieved,demonstrating excellent single photon detection performance.
基金Financial provided by the National Natural Science Foundation of China (Nos. 51574123 and U1361118)the China Postdoctoral Science Foundation (No. 2015M 582118)
文摘To master theoretical calculation for dust removal efficiency of high pressure atomization in an underground coal mine, the corresponding atomization characteristics and dust removal efficiency were both comprehensively studied in theory by virtue of related theories of hydromechanics and aerosol.According to actual measurements of flow coefficients and atomization angles of X-type swirl nozzle,computational formula was derived for atomized particle sizes of such a nozzle in conjunction with relevant empirical equation. Moreover, a mathematical model for applying high pressure atomization to dust removal in underground coal mine was also established to deduce theoretical computation formula of fractional efficiency. Then, Matlab was adopted to portray the relation curve between fractional efficiency and influence factors. In addition, a theoretical formula was also set up for removal efficiency of respirable dust and total coal dust based on dust size and frequency distribution equations. In the end,impacts of dust characteristic parameters on various dust removal efficiencies were analyzed.
基金supported by a grant (Code # 413-111-004) from Eco Innovation Project funded by Ministry of Environment of Korea government
文摘Using total suspended solid (TSS) removal efficiency and hydraulic retention time (HRT) as design parameters a design guideline of a settling basin in a constructed wetland (CW) was suggested; as well as management of sediment and particle in the settling basin. The CW was desiEned to treat the piggery wastewater effluent from a wastewater treatment plant during dry days and stonnwater runoff from the surrounding paved area during wet days. The first settling basin (FSB) in the CVV was theoretically designed with a total storage volume (TSV) of 453 ms and HRT of 5.5 hr. The amount of sediment and particles settled at the FSB was high due to the sedimentation and interception of plants in the CVV. Dredging of sediments was performed when the retention rate at the FSB decreased to approximately 80%. Findings showed that the mean flow rate was 21.8 m3/hr less than the designed flow rate of 82.8 m3/hr indicating that the FSB was oversize and operated with longer HRT (20.7 hr) compared to the design HRT. An empirical model to estimate the length of the settling basin in the CW was developed as a function of HRT and desired TSS removal efficiency. Using the minimum tolerable TSS removal efficiency of 30%, the length of the FSB was estimated to be 31.2 m with 11.8 hr HRT.
基金Project(2009ZX07315-005) supported by the National Water Pollution Controlled and Treatment Great Special of China
文摘The nitrate nitrogen removal efficiency of iron-carbon micro-electrolysis system was discussed in treating pharmaceutical wastewater with high nitrogen and refractory organic concentration. The results show that the granularity of fillings,pH,volume ratios of iron-carbon and gas-water,and HRT. have significant effects on the nitrogen removal efficiency of iron-carbon micro-electrolysis system. The iron-carbon micro-electrolysis system has a good removal efficiency of pharmaceutical wastewater with high nitrogen and refractory organic concentration when the influent TN,NH4+-N,NO3--N and BOD5/CODCr are 823 mg/L,30 mg/L,793 mg/L and 0.1,respectively,at the granularity of iron and carbon 0.425 mm,pH 3,iron-carbon ratio 3,gas-water ratio 5,HRT 1.5 h,and the removal rates of TN,NH4+-N and NO3--N achieve 51.5%,70% and 50.94%,respectively.
基金the National Science Foundation for Distinguished Young Scholars of China (No.50525722)the Science and Technology research key project of MOE
文摘In this paper, an experimental study on SO2 removal by nanosecond rising edge pulse dielectric barrier discharge (DBD) plasma, generated by multi-needle-to-plane electrodes, is carried out. The mechanism of the effect of various factors, such as gap size between dielectric barrier and discharge needles, environmental humidity, and inlet speed of gas flow upon the removal efficiency of air purification is analyzed. The studies show that SOs removal efficiency improves with the increase in the gap size between dielectric barrier and discharge needles in the case of a fixed space between two electrodes, and also improves with the increase in the environmental humidity. For a mixed gas with a fixed concentration, there is an optimal inlet speed of gas flow, which leads to the best removal efficiency.
基金supported by the National Key Research and Development Programme of China(No.2016YFC 0401103)the National Natural Science Foundation of China(No.51408387)the Jiangsu Collaborative Innovation Center of Technology and Material of Water Treatment
文摘In order to reduce the amount of NO_3^-–N generated by the Anammox process, and alleviate the competition between denitrification and Anammox for NO_2^-–N in a single reactor, the preference of S^0 for reacting with coexisting NO_2^-–N and NO_3^-–N in the sulfur autotrophic denitrifying(SADN) process and the coupling effect of short-cut SADN and the Anammox process were studied. The results showed that S^0 preferentially reacted with NO_3^-to produce NO_2^-–N, and then reacted with NO_2^-–N when NO_3^-–N was insufficient, which could effectively alleviate the competition between SADN bacteria(SADNB) and Anammox bacteria(An AOB) for NO_2^-–N. After 170 days of operation, coupling between short-cut S^0-SADN and the Anammox process was first successfully achieved. SADNB converted the NO_3^-–N generated by the Anammox process into NO_2^-–N, which was once again available to An AOB. The total nitrogen removal efficiency eventually stabilized at over 95%, and the effluent NO_3^-–N was controlled within 10 mg/L, when high NH_4^+–N wastewater was treated by the Anammox process. Microbial community analysis further showed that Candidatus Brocadia and Thiobacillus were the functional microorganisms for An AOB and SADNB.
基金National Natural Science Foundation of China(No.21725404)Shanghai Scientific and Technological Innovation Project(No.18JC1410600)the Strategic Priority Research Program of the Chinese Academy of Sciences(No.XDB20000000)financial support。
文摘A heteropore covalent organic framework(COF) integrating tetraphenylethene skeleton and catechol segment is designed and synthesized.It exhibits extremely high stability in water under different pH conditions,which makes it an excellent material for adsorptive removal of Cd(Ⅱ) from aqueous solutions with very fast adsorption kinetics,high uptake capacity,and good recyclability.
文摘Large quantities of sludge are produced during water treatment processes. Recently, sludge has been treated as waste and disposed of in landfills, which increases the environmental burdens and the operational cost. Therefore, sludge reuse has become a significant environmental issue. In this study, adsorption of copper ions (Cu^2+) onto calcined sludge was investigated under various operational conditions (with varying temperature, Cu^2+ initial concentration, pH, and sludge dosage). The prepared sludge material was characterized with transmission electron microscopy (TEM), X-ray diffraction (XRD), dynamic light scattering (DLS), and Brunauer-Emmett-Teller (BET) surface area. The sorption capacity of sludge was directly proportional to the initial Cu^2+ concentration and inversely proportional to the sludge dosage. The optimum operational pH and solution temperature were 6.6 and 80℃, respectively. The experimental results followed a Langmuir isotherm and pseudo-first-order adsorption kinetics. Thermodynamic parameters such as activation energy, change in free energy, enthalpy, and entropy were calculated. Thermodynamic analyses indicated that the sorption of copper ions onto the calcined sludge was driven by a physical adsorption process. The prepared sludge was proven to be an excellent adsorbent material for the removal of Cu^2+ from an aqueous solution under optimum conditions.
基金Supported by National Natural Science Foundation of China(Nos.50378004 and 50678007)Beijing Natural Science Foun-dation(No.8082009)+1 种基金Science & Technology Development Programme of Beijing Municipal Commission of Education (No.KM200610005025)Academic Human Resources Development in Institutions of Higher Learning Under the Jurisdiction of Beijing Municipality(No. 05004014200701).
文摘Iron-manganese composited oxide(FeMnO) was prepared with potassium permanganate and ferrous salt. Interface performance, charge property and structure topography of the FeMnO were investigated. Coagulation efficiency and pollution removal mechanism of the FeMnO were approached. Results show that the main compositions of the FeMnO are δ-manganese dioxide and ferric hydroxide. The specific surface area is about 146.22 m^2/g. The FeMnO contains rich hydroxyl with extremely strong adsorption action and chemical adsorption activity. The zero charge point of the oxide in pure water is about 8.0 of pH value. Under neutral pH value conditions, the FeMnO particle surface carried positive charges. The FeMnO particles are quasi-spherical micro-particles with irregular sizes adjoined each other to form net construction. Phosphorus removal efficiency of the FeMnO is remarkable, the total dissoluble phosphorus of settled water can be reduced below detecting level(0.3 μtg/L) at a FeMnO dosage of 6 mg/L, and total phosphorus below detecting level at a FeMnO dosage of 10 mg/L, for water samples containing total phos- phorus of 1281.70 μg/L and total dissoluble phosphorus of 1187.91 μtg/L. The mechanism of effective coagulation for phosphorus removal is combined results of multiple actions of adsorption, charge neutralization, adsorption/bridging and so on.
文摘This paper describes the preparation of a membrane of polyacrylonitrile(PAN)and its corresponding membrane coated with polyaniline(PANI)for the adsorption of heavy metal ions.Scanning electron microscopy micrographs revealed that all the membranes exhibited nanofibrous morphology.The prepared membranes were characterized by Fourier transform infrared spectroscopy(FTIR).The prepared membranes were used as an adsorbent for hazardous heavy metal ions Pb^(2+) and Cr_(2)O^(2-)_(7).The adsorption capacity and the removal efficiency of the membranes were examined as function of the initial adsorbate concentration and pH of the medium.Coated membranes with PANI showed better adsorption performance and their direct current(DC)conductivities were correlated to heavy metal ion concentrations.Adsorption isotherms were also performed,and the adsorption process was tested according to the Langmuir and Freundlich models.The regeneration and reuse of the prepared membranes to re-adsorb heavy metal ions were also investigated.The enhancement in adsorption performance and reusability of PANI-coated membranes in comparison with non-coated ones is fully discussed.The results show that the maximum adsorption capacities of lead and chromate ions on the PANI-coated membranes are 290.12 and 1202.53 mg/g,respectively.
基金We thank Esther Posner,PhD,from Edanz Group China(www.liwenbianji.cn/ac)for English language editing on an earlier draft of this manuscript.This work was supported by the 2017 Hunan Provincial Graduate Research Innovation Project of China(No.CX2017B649)the National Natural Science Foundation of China(No.51774134)+2 种基金the Excellent Youth Project of Hunan Provincial Department of Education(No.19B223)the Hunan Provincial Natural Science Foundation of China(No.2019JJ60044)the Hunan Provincial Natural Science Foundation of China(No.2018JJ64028).
文摘Based onmultiphase flowtheory and capillary mechanics,the dimensionless bond number expression of the influence of string grille wire spacing on droplet spreading is derived.Taking a liquid film formed by spreading droplets based on Kelvin correlation,the Young-Laplace equation,and the Hagen-Poiseuille law,an equation for calculating the thickness and height of the liquid film is established with temperature,relative humidity and molar volume of liquid phase as independent variables.According to the theory of string grille filtration and dust removal,a dust removal efficiency calculation model covering the wet string grille wire group is constructed based on the liquid film thickness,height,wire diameter,water film area,and vortex shedding frequency.Finally,a theoretical analysis of the influence of water film area on the efficiency of wet string grille dust removal is carried out based on the spray pressure and the ratio of string grille wire distance to wire diameter.It is found that the effect of spray pressure on water film area and dust removal efficiency is more significant than the string grille wire distance diameter ratio.Moreover,the optimized combination of wet string grille wire distance diameter ratio 0.84,wind speed 3m/s and spray pressure 0.8 MPa is found,which could provide an important reference for engineering applications.