The mechanism of hydrate-based desalination is that water molecules would transfer to the hydrate phase during gas hydrate formation process,while the salt ions would be conversely concentrated in the unreacted saltwa...The mechanism of hydrate-based desalination is that water molecules would transfer to the hydrate phase during gas hydrate formation process,while the salt ions would be conversely concentrated in the unreacted saltwater.However,the salt concentration of hydrate decomposed water and the desalination degree of hydrate phase are still unclear.The biggest challenge is how to effectively separate the hydrate phase and the remaining unreacted salt water,and then decompose the hydrate phase to measure the salt concentration of hydrate melt water.This work developed an apparatus and pressure-driven filtration method to efficiently separate the hydrate phase and the remaining unreacted saltwater.On this basis,the single hydrate phase was obtained,then it was dissociated and the salt concentration of hydrate melt water was measured.The experimental results demonstrate that when the initial salt mass concentration is 0.3% to 8.0%,the salt removal efficiency for NaCl solution is 15.9% to 29.8%by forming CO_(2) hydrate,while for CaCl_(2) solution is 28.9%to 45.5%.The solute CaCl_(2) is easier to be removed than solute NaCl.In addition,the salt removal efficiency for forming CO_(2) hydrate is higher than that for forming methane hydrate.The multi-stage desalination can continuously decrease the salt concentration of hydrate dissociated water,and the salt removal efficiency per stage is around 20%.展开更多
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
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
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
The non-thermal plasma created by high voltage pulsed power supply can be used to remove sulfur dioxide in the air, but how to increase the removing efficiency is not clear. It is novel to apply the magnetic field in ...The non-thermal plasma created by high voltage pulsed power supply can be used to remove sulfur dioxide in the air, but how to increase the removing efficiency is not clear. It is novel to apply the magnetic field in removing SO2 as discussed in this paper. The mechanisms of removing sulfur dioxide by non-thermal plasma along with the application of the magnetic field are analyzed, and the related factors affecting the removal efficiency, such as the magnitude of pulsed voltage, the polarity of the pulse, the layout of the discharge electrode, especially the magnetic field are experimentally investigated. It can be concluded that the purification efficiency is improved significantly by applying the magnetic field.展开更多
Ammonia in wastewater is a major pollutant produced in industrial and agricultural wastewaters. Ammonia is often removed by conventional technologies such as pack tower aeration, biological treatment or adsorption as ...Ammonia in wastewater is a major pollutant produced in industrial and agricultural wastewaters. Ammonia is often removed by conventional technologies such as pack tower aeration, biological treatment or adsorption as ammonium ion onto zeolites. In many cases, conventional methods are very costly and inefficient, and therefore there is a need for an alternative separation technique for more efficient removal of ammonia from wastewaters. The aim of this study is to investigate the performance of combination of ozonation and absorption through membrane processes to remove ammonia from wastewater using NHSW (natural hot spring water) as absorbent. Experimental results show that hollow fiber membrane contactor has potential application for ammonia removal from wastewater. Operating variables such as time and pH of absorbent solution are found to remarkably influence the removal process efficiency.. Based on experimental results ozonation can improve ammonia removal efficiency through hollow fiber membrane contactor. Ammonia removal efficiencies and overall mass transfer coefficients increase with decreasing pH of absorbent solution.展开更多
Niobium oxide nanowire-deposited carbon fiber(CF) samples were prepared using a hydrothermal method with amorphous Nb2O5·nH2O as precursor. The physical properties of the samples were characterized by means of ...Niobium oxide nanowire-deposited carbon fiber(CF) samples were prepared using a hydrothermal method with amorphous Nb2O5·nH2O as precursor. The physical properties of the samples were characterized by means of numerous techniques, including X-ray diffraction(XRD), energy-dispersive spectroscopy(EDS), scanning electron microscopy(SEM), transmission electron microscopy(TEM), selected-area electron diffraction(SAED), UV–visible spectroscopy(UV–vis), N2 adsorption–desorption, Fourier transform infrared spectroscopy(FT-IR), and X-ray photoelectron spectroscopy. The efficiency for the removal of Cr(VI) was determined.Parameters such as pH value and initial Cr(VI) concentration could influence the Cr(VI) removal efficiency or adsorption capacity of the Nb2O5/carbon fiber sample obtained after hydrothermal treatment at 160°C for 14 hr. The maximal Cr(VI) adsorption capacity of the Nb2O5 nanowire/CF sample was 115 mg/g. This Nb2O5/CF sample also showed excellent photocatalytic activity and stability for the reduction of Cr(Ⅵ) under UV-light irradiation: the Cr(VI) removal efficiency reached 99.9% after UV-light irradiation for 1 hr and there was no significant decrease in photocatalytic performance after the use of the sample for 10 repeated cycles. Such excellent Cr(VI) adsorption capacity and photocatalytic performance was related to its high surface area,abundant surface hydroxyl groups, and good UV-light absorption ability.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
Electromagnetic separation of non-metallic inclusions from Al-Si melt is studied by theoretical analysis and experiments on self-designed electromagnetic separation apparatus. Metallographs and LECO Image Analysis Sy...Electromagnetic separation of non-metallic inclusions from Al-Si melt is studied by theoretical analysis and experiments on self-designed electromagnetic separation apparatus. Metallographs and LECO Image Analysis System were used to analyze the content of alumina in aluminum alloy before and after electromagnetic separation. It is seen that removal effciency increases with the increase of electromagnetic force (EMF) and diameter of inclusion particles while decreases with the increase of melt velocity and height of separator. All alumina particles with diamete of 14μm have been removed successfully from the melt.展开更多
To evaluate the removal efficiency of organic pollutants in the sewage by Harbin municipal sewage treatment plant, the influent and effluent samples from the plant were pretreated by liquid-liquid extraction (LLE) u...To evaluate the removal efficiency of organic pollutants in the sewage by Harbin municipal sewage treatment plant, the influent and effluent samples from the plant were pretreated by liquid-liquid extraction (LLE) under conditions of acidity, neutrality and alkaleseence in sequence, and then were analyzed by gas chromatograph-mass spectrum (GC-MS) procedures. Results indicate that there are 70 species of organic pollutants in the influent sample of the plant, which mainly consist of alkyls, benzene series, esters, and heteroeyclic compounds. Some of these organic pollutants are biotoxie and belong to persistent organic pollutants (POPs). Four species among them are on the list of Prior Pollutants of Environmental Protection Agency of USA (USEPA). However, 7 species of organic pollutants appearing in the effluent sample mainly include alkyls of multi-carbons and phthalate esters. The removal efficiency of phthalates is poor because of their poor biodegradability. The sewage treatment technique is effective in removing most+of organics pollutants.展开更多
As the main equipment of flue gas dedusting in coal fired boiler,electrostatic precipitator(ESP)can meet the requirements of emission standard for air pollutants from coal-fired power plants through improving the effi...As the main equipment of flue gas dedusting in coal fired boiler,electrostatic precipitator(ESP)can meet the requirements of emission standard for air pollutants from coal-fired power plants through improving the efficiency of ESP and combining with desulfurization system while not installing wet ESP(WESP).This paper introduces the modifications of ESP cathode structure to improve the efficiency of dust collection by reducing the secondary dust loss at cathode.The application of cathode dust collection provides a reference for the improvement of ESP dust collection efficiency.展开更多
Ultra-precision components have been widely used to produce advanced optoelectronic equipment.The so-called Electric field enhanced UltraViolet-Induced Jet Machining(EUV-INCJM)is an ultra-precision method that can ach...Ultra-precision components have been widely used to produce advanced optoelectronic equipment.The so-called Electric field enhanced UltraViolet-Induced Jet Machining(EUV-INCJM)is an ultra-precision method that can achieve sub-nanometer level surface quality polishing.This study focuses on the application of the EUV-INCJM with different nozzle structures to a single-crystal of silicon.Two kinds of electro-optic-liquid coupling nozzles with single-jet and multi-jet focusing structures are proposed accordingly.Simulations and experiments have been conducted to verify the material removal performance of these nozzles.The simulation results show that,under the same condition,the flow velocity of the single-jet nozzle is 1.05 times higher than that achieved with the multi-jet configuration,while the current density of the latter is 1.63 times higher than that of the single-jet nozzle.For the single-crystal silicon,the material removal efficiency of the multi-jet focusing nozzle exceeds by about 1.4 times that of the single-jet.These results confirm that the material removal ability of the multi-jet configuration is more suitable for ultra-smooth surface polishing.The surface roughness of Si workpiece was reduced from Rq 1.55 to Rq 0.816 nm with valleys and peaks on its surface being almost completely removed.展开更多
The nanocrystalline samples Nd_(1-x)M_(x)FeO_(3)(x=0.0 and 0.1;M:Co^(2+)and Ni^(2+))were prepared using the citrate combustion method.The X-ray diffraction(XRD)pattern confirmed that the nanoparticles were synthesized...The nanocrystalline samples Nd_(1-x)M_(x)FeO_(3)(x=0.0 and 0.1;M:Co^(2+)and Ni^(2+))were prepared using the citrate combustion method.The X-ray diffraction(XRD)pattern confirmed that the nanoparticles were synthesized in an orthorhombic structure.The particle size of Nd_(1-x)M_(x)FeO_(3) is in the range of 29-59 nm.The selected area electron diffraction(SAED)indicates the samples were prepared in a polycrystalline nature.The samples Nd_(1-x)M_(x)FeO_(3)(x=0.0 and 0.1;M:Co^(2+)and Ni^(2+))have anti ferromagnetic behavior.The Fe^(3+)spins are aligned antiparallel,forming the antiferromagnetic(AFM)properties,which are affected by many factors such as the bond angle between the Fe^(3+)(Fe^(3+)-O_(2)--Fe^(3+))and the Dzyaloshinskii-Moriya(D-M)interaction.The doping of Co^(2+)and Ni^(2+)ions in NdFeO_(3) enhances the magnetic properties of the NdFeO_(3).The saturation magnetization(Ms)of Nd_(0.90)Co_(0.10)FeO_(3) increases 1.8times more than that of NdFeO_(3).The exchange bias field(HEX)of the Co-doped sample is two times greater than that of NdFeO_(3).The magnetic anisotropy constant(K)of the 10%Co-doped sample increases by 11 factors compared to that of NdFeO_(3).The Tauc plot illustrates that the samples have a direct optical transition.The divalent cation substitution(Co^(2+)and Ni^(2+))decreases the optical band gap of NdFeO_(3),leading to the recommendation of using the samples Nd_(0.90)Co_(0.10)FeO_(3) and Nd_(0.90)Ni_(0.10)FeO_(3) in photocatalysis of dye degradation from water.The removal efficiencies of Cr6+at pH=6 are 88.06%,85.54%,and 85.52%for the samples NdFeO_(3),Nd_(0.90)Co_(0.10)FeO_(3),and Nd_(0.90)Ni_(0.10)FeO_(3),respectively.The Freundlich isotherm mode is the best-fit model for NdFeO_(3) to adsorb Cr6+ions from aqueous solutions.展开更多
The abundance of microplastics(MPs)in wastewater from three wastewater treatment plants(WWTPs)were determined in Hangzhou,Zhejiang Province,China.The MPs abundance was 140-350 particles per litre in the influent and 1...The abundance of microplastics(MPs)in wastewater from three wastewater treatment plants(WWTPs)were determined in Hangzhou,Zhejiang Province,China.The MPs abundance was 140-350 particles per litre in the influent and 10-30 particles per litre in the effluent.Four shapes of MPs in the influent were observed,while mainly only debris was left in the effluent.The percentage of small(<100μm),medium(100-500μm),and large-sized(≥500μm)plastics in the raw leachate of the three WWTPs were 54.3%,8.6%,and 37.1%,28.6%,64.3%,and 7.1%,and 41.4%,24.1%,and 34.5%,respectively.Mainly only the size of≤100μm was left in the effluent of all.The removal efficiencies of MPs in a range of 78.6%to 96.6%were achieved.Polypropylene,polystyrene,polyethylene,polyethylene terephthalate and polyvinyl chloride were the main types and detected in all wastewater samples,accounting for over 75%of all types.The plastic components contained in different industrial wastewater were more complex.The distribution of MPs was significantly positively correlated with most conventional indicators such as chemical oxygen demead,ammonia nitrogen,and total phosphorus,but not with heavy metals.Similar wastewater,different treatment processes,or similar processes but different wastewater(industrial wastewater proportion varied)could all lead to differences in MPs removal.The MPs abundance measured in this experiment was similar to some previous studies,but relatively high.The three WWTPs can discharge up to 6.0×10^(-8)-1.8×10^(-9) plastics of MPs per day,which poses potential ecological risks.This study indicates that the source control of MPs and optimizing the process design of existing WWTPs are crucial for preventing and controlling MPs pollution.展开更多
Antibiotic resistance genes(ARGs)are proposed as emerging environmental pollutants and pose potential threat to public health globally.The efficient removal of ARGs and prevention of their spread in the environment ar...Antibiotic resistance genes(ARGs)are proposed as emerging environmental pollutants and pose potential threat to public health globally.The efficient removal of ARGs and prevention of their spread in the environment are of great concern.Wastewater treatment plants are among the hotspot of ARGs transmission,however,while both conventional and advanced water treatment processes cannot effectively remove ARGs.Therefore,employing advanced materials including Mxenes,black phosphorus and single atom catalysts in the elimination of pollutants such as ARGs has garnered attention.In this review,first of all,the characteristics of ARGs and environmental parameters,which include pH and ions that influences ARGs removal were elucidated.Secondly,different types of materials used to remove ARGs were summarized.The removalmechanisms of ARGsweremainly related to adsorption(active sites)and degradation(radical and non-radical way).Finally,the design strategies for materials employed in ARGs removal were proposed.This review improves our understanding of the important roles of the traditional and advanced materials in the management of ARGs pollution.展开更多
Microbial fuel cells(MFCs)face significant challenges related to low power output,which severely limits their practical applications.Coupling MFC with other technologies and stacking MFCs are feasible solutions to enh...Microbial fuel cells(MFCs)face significant challenges related to low power output,which severely limits their practical applications.Coupling MFC with other technologies and stacking MFCs are feasible solutions to enhance power output.In recent years,the coupling and stacking technology of MFCs has become a research hotspot in the field of environmental energy.This paper first outlines the basic configurations of MFCs and then analyzes the advantages and disadvantages of different setups in the context of coupling and stacking.Subsequently,it discusses in detail the coupling systems of MFC with other technologies,as well as several configurations of stacked MFCs and the phenomenon of voltage reversal.Based on these investigations,the paper proposes future research directions aimed at optimizing MFC performance,thereby enhancing their potential for energy recovery from wastewater and supporting the commercialization and scaling of MFC technology.展开更多
Gas blowing is a valid method to remove the impurities from metallurgical grade silicon(MG-Si) melt.The thermodynamic behavior of impurities Fe,Al,Ca,Ti,Cu,C,B and P in MG-Si was studied in the process of O2 blowing...Gas blowing is a valid method to remove the impurities from metallurgical grade silicon(MG-Si) melt.The thermodynamic behavior of impurities Fe,Al,Ca,Ti,Cu,C,B and P in MG-Si was studied in the process of O2 blowing.The removal efficiencies of impurities in MG-Si were investigated using O2 blowing in ladle.It is found that the removal efficiencies are higher than 90% for Ca and Al and nearly 50% for B and Ti.The morphology of inclusions was analyzed and the phases Al3Ni,NiSi2 and Al3Ni were confirmed in MG-Si by X-ray diffraction.It was found that SiB4 exists in Si?B binary system.The chemical composition of inclusions in MG-Si before and after refining was analyzed by SEM-EDS.It is found that the amount of white inclusion reduces for the removal of most Al and Ca in the forms of molten slag inclusion and the contents of Fe,Ni and Mn in inclusion increase for their inertia in silicon melt with O2 blowing.展开更多
[Objective] The study was conducted to optimize the operation parameters of water control equipment for deep-litter beddings. [Method] A four-factor three-level orthogonal design was adopted to optimize experimental t...[Objective] The study was conducted to optimize the operation parameters of water control equipment for deep-litter beddings. [Method] A four-factor three-level orthogonal design was adopted to optimize experimental temperature, stopping time of aeration, aeration time and aeration rate by 9 groups of experiments, so as to improve the water removal efficiency of adopted mixed and reduce operation energy consumption. [Result] The average water contents in the mixed bedding under 3 temperatures decreased by 4.58% ±2.91%, 13.17% ±3.77% and 10.8% ±7.72%, respectively; the highest water removal efficiency could be achieved under an experimental temperature at 45 ℃, stopping time of aeration of 15 min, aeration time of 7 min, and an aeration rate at 4 m^3/min, which formed the optimal factor combination mode of the operation parameter of the water control equipment; the effects of various experimental factors on water content in the bedding were in order of aeration ratetemperatureaeration timestopping time of aeration; and the effects of various experimental factors on water removal efficiency in the bedding were in order of temperatureaeration rateaeration timestopping time of aeration. [Conclusion] After the optimization of operation parameters of the water control equipment for the deep-litter bedding, water removal efficiency of the mixed bedding could be improved, and the operation energy consumption of the equipment could be reduced.展开更多
基金The financial support from the National Natural Science Foundation of China(22127812,22278433,22178379)the National Key Research and Development Program of China(2021YFC2800902)are gratefully acknowledged。
文摘The mechanism of hydrate-based desalination is that water molecules would transfer to the hydrate phase during gas hydrate formation process,while the salt ions would be conversely concentrated in the unreacted saltwater.However,the salt concentration of hydrate decomposed water and the desalination degree of hydrate phase are still unclear.The biggest challenge is how to effectively separate the hydrate phase and the remaining unreacted salt water,and then decompose the hydrate phase to measure the salt concentration of hydrate melt water.This work developed an apparatus and pressure-driven filtration method to efficiently separate the hydrate phase and the remaining unreacted saltwater.On this basis,the single hydrate phase was obtained,then it was dissociated and the salt concentration of hydrate melt water was measured.The experimental results demonstrate that when the initial salt mass concentration is 0.3% to 8.0%,the salt removal efficiency for NaCl solution is 15.9% to 29.8%by forming CO_(2) hydrate,while for CaCl_(2) solution is 28.9%to 45.5%.The solute CaCl_(2) is easier to be removed than solute NaCl.In addition,the salt removal efficiency for forming CO_(2) hydrate is higher than that for forming methane hydrate.The multi-stage desalination can continuously decrease the salt concentration of hydrate dissociated water,and the salt removal efficiency per stage is around 20%.
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The project supported by the Teaching and Research Award Program for Outstanding Young Teachers in Higher EducationInstitutions under the MOE, China (No. 123-2002)
文摘The non-thermal plasma created by high voltage pulsed power supply can be used to remove sulfur dioxide in the air, but how to increase the removing efficiency is not clear. It is novel to apply the magnetic field in removing SO2 as discussed in this paper. The mechanisms of removing sulfur dioxide by non-thermal plasma along with the application of the magnetic field are analyzed, and the related factors affecting the removal efficiency, such as the magnitude of pulsed voltage, the polarity of the pulse, the layout of the discharge electrode, especially the magnetic field are experimentally investigated. It can be concluded that the purification efficiency is improved significantly by applying the magnetic field.
文摘Ammonia in wastewater is a major pollutant produced in industrial and agricultural wastewaters. Ammonia is often removed by conventional technologies such as pack tower aeration, biological treatment or adsorption as ammonium ion onto zeolites. In many cases, conventional methods are very costly and inefficient, and therefore there is a need for an alternative separation technique for more efficient removal of ammonia from wastewaters. The aim of this study is to investigate the performance of combination of ozonation and absorption through membrane processes to remove ammonia from wastewater using NHSW (natural hot spring water) as absorbent. Experimental results show that hollow fiber membrane contactor has potential application for ammonia removal from wastewater. Operating variables such as time and pH of absorbent solution are found to remarkably influence the removal process efficiency.. Based on experimental results ozonation can improve ammonia removal efficiency through hollow fiber membrane contactor. Ammonia removal efficiencies and overall mass transfer coefficients increase with decreasing pH of absorbent solution.
基金financially supported by the major Project of the national science and technology of China (No. SQ2017YFGX010248)the Beijing Natural Science Foundation (No. 2172011)
文摘Niobium oxide nanowire-deposited carbon fiber(CF) samples were prepared using a hydrothermal method with amorphous Nb2O5·nH2O as precursor. The physical properties of the samples were characterized by means of numerous techniques, including X-ray diffraction(XRD), energy-dispersive spectroscopy(EDS), scanning electron microscopy(SEM), transmission electron microscopy(TEM), selected-area electron diffraction(SAED), UV–visible spectroscopy(UV–vis), N2 adsorption–desorption, Fourier transform infrared spectroscopy(FT-IR), and X-ray photoelectron spectroscopy. The efficiency for the removal of Cr(VI) was determined.Parameters such as pH value and initial Cr(VI) concentration could influence the Cr(VI) removal efficiency or adsorption capacity of the Nb2O5/carbon fiber sample obtained after hydrothermal treatment at 160°C for 14 hr. The maximal Cr(VI) adsorption capacity of the Nb2O5 nanowire/CF sample was 115 mg/g. This Nb2O5/CF sample also showed excellent photocatalytic activity and stability for the reduction of Cr(Ⅵ) under UV-light irradiation: the Cr(VI) removal efficiency reached 99.9% after UV-light irradiation for 1 hr and there was no significant decrease in photocatalytic performance after the use of the sample for 10 repeated cycles. Such excellent Cr(VI) adsorption capacity and photocatalytic performance was related to its high surface area,abundant surface hydroxyl groups, and good UV-light absorption ability.
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.
基金This work supported by the National Natural Science Foundation of China(Grant,No.59871029)the National Key Fundamental Research Project(973)(No.G1999064900)
文摘Electromagnetic separation of non-metallic inclusions from Al-Si melt is studied by theoretical analysis and experiments on self-designed electromagnetic separation apparatus. Metallographs and LECO Image Analysis System were used to analyze the content of alumina in aluminum alloy before and after electromagnetic separation. It is seen that removal effciency increases with the increase of electromagnetic force (EMF) and diameter of inclusion particles while decreases with the increase of melt velocity and height of separator. All alumina particles with diamete of 14μm have been removed successfully from the melt.
文摘To evaluate the removal efficiency of organic pollutants in the sewage by Harbin municipal sewage treatment plant, the influent and effluent samples from the plant were pretreated by liquid-liquid extraction (LLE) under conditions of acidity, neutrality and alkaleseence in sequence, and then were analyzed by gas chromatograph-mass spectrum (GC-MS) procedures. Results indicate that there are 70 species of organic pollutants in the influent sample of the plant, which mainly consist of alkyls, benzene series, esters, and heteroeyclic compounds. Some of these organic pollutants are biotoxie and belong to persistent organic pollutants (POPs). Four species among them are on the list of Prior Pollutants of Environmental Protection Agency of USA (USEPA). However, 7 species of organic pollutants appearing in the effluent sample mainly include alkyls of multi-carbons and phthalate esters. The removal efficiency of phthalates is poor because of their poor biodegradability. The sewage treatment technique is effective in removing most+of organics pollutants.
文摘As the main equipment of flue gas dedusting in coal fired boiler,electrostatic precipitator(ESP)can meet the requirements of emission standard for air pollutants from coal-fired power plants through improving the efficiency of ESP and combining with desulfurization system while not installing wet ESP(WESP).This paper introduces the modifications of ESP cathode structure to improve the efficiency of dust collection by reducing the secondary dust loss at cathode.The application of cathode dust collection provides a reference for the improvement of ESP dust collection efficiency.
基金supported by the National Natural Science Foundation of China(52365056).
文摘Ultra-precision components have been widely used to produce advanced optoelectronic equipment.The so-called Electric field enhanced UltraViolet-Induced Jet Machining(EUV-INCJM)is an ultra-precision method that can achieve sub-nanometer level surface quality polishing.This study focuses on the application of the EUV-INCJM with different nozzle structures to a single-crystal of silicon.Two kinds of electro-optic-liquid coupling nozzles with single-jet and multi-jet focusing structures are proposed accordingly.Simulations and experiments have been conducted to verify the material removal performance of these nozzles.The simulation results show that,under the same condition,the flow velocity of the single-jet nozzle is 1.05 times higher than that achieved with the multi-jet configuration,while the current density of the latter is 1.63 times higher than that of the single-jet nozzle.For the single-crystal silicon,the material removal efficiency of the multi-jet focusing nozzle exceeds by about 1.4 times that of the single-jet.These results confirm that the material removal ability of the multi-jet configuration is more suitable for ultra-smooth surface polishing.The surface roughness of Si workpiece was reduced from Rq 1.55 to Rq 0.816 nm with valleys and peaks on its surface being almost completely removed.
文摘The nanocrystalline samples Nd_(1-x)M_(x)FeO_(3)(x=0.0 and 0.1;M:Co^(2+)and Ni^(2+))were prepared using the citrate combustion method.The X-ray diffraction(XRD)pattern confirmed that the nanoparticles were synthesized in an orthorhombic structure.The particle size of Nd_(1-x)M_(x)FeO_(3) is in the range of 29-59 nm.The selected area electron diffraction(SAED)indicates the samples were prepared in a polycrystalline nature.The samples Nd_(1-x)M_(x)FeO_(3)(x=0.0 and 0.1;M:Co^(2+)and Ni^(2+))have anti ferromagnetic behavior.The Fe^(3+)spins are aligned antiparallel,forming the antiferromagnetic(AFM)properties,which are affected by many factors such as the bond angle between the Fe^(3+)(Fe^(3+)-O_(2)--Fe^(3+))and the Dzyaloshinskii-Moriya(D-M)interaction.The doping of Co^(2+)and Ni^(2+)ions in NdFeO_(3) enhances the magnetic properties of the NdFeO_(3).The saturation magnetization(Ms)of Nd_(0.90)Co_(0.10)FeO_(3) increases 1.8times more than that of NdFeO_(3).The exchange bias field(HEX)of the Co-doped sample is two times greater than that of NdFeO_(3).The magnetic anisotropy constant(K)of the 10%Co-doped sample increases by 11 factors compared to that of NdFeO_(3).The Tauc plot illustrates that the samples have a direct optical transition.The divalent cation substitution(Co^(2+)and Ni^(2+))decreases the optical band gap of NdFeO_(3),leading to the recommendation of using the samples Nd_(0.90)Co_(0.10)FeO_(3) and Nd_(0.90)Ni_(0.10)FeO_(3) in photocatalysis of dye degradation from water.The removal efficiencies of Cr6+at pH=6 are 88.06%,85.54%,and 85.52%for the samples NdFeO_(3),Nd_(0.90)Co_(0.10)FeO_(3),and Nd_(0.90)Ni_(0.10)FeO_(3),respectively.The Freundlich isotherm mode is the best-fit model for NdFeO_(3) to adsorb Cr6+ions from aqueous solutions.
基金funded by the National Natural Science Foundation of China(42477406,51878617)the horizontal scientific research project(KYY-HX-20220803)the Engineering Research Center of Ministry of Education for Renewable Energy Infrastructure Construction Technology。
文摘The abundance of microplastics(MPs)in wastewater from three wastewater treatment plants(WWTPs)were determined in Hangzhou,Zhejiang Province,China.The MPs abundance was 140-350 particles per litre in the influent and 10-30 particles per litre in the effluent.Four shapes of MPs in the influent were observed,while mainly only debris was left in the effluent.The percentage of small(<100μm),medium(100-500μm),and large-sized(≥500μm)plastics in the raw leachate of the three WWTPs were 54.3%,8.6%,and 37.1%,28.6%,64.3%,and 7.1%,and 41.4%,24.1%,and 34.5%,respectively.Mainly only the size of≤100μm was left in the effluent of all.The removal efficiencies of MPs in a range of 78.6%to 96.6%were achieved.Polypropylene,polystyrene,polyethylene,polyethylene terephthalate and polyvinyl chloride were the main types and detected in all wastewater samples,accounting for over 75%of all types.The plastic components contained in different industrial wastewater were more complex.The distribution of MPs was significantly positively correlated with most conventional indicators such as chemical oxygen demead,ammonia nitrogen,and total phosphorus,but not with heavy metals.Similar wastewater,different treatment processes,or similar processes but different wastewater(industrial wastewater proportion varied)could all lead to differences in MPs removal.The MPs abundance measured in this experiment was similar to some previous studies,but relatively high.The three WWTPs can discharge up to 6.0×10^(-8)-1.8×10^(-9) plastics of MPs per day,which poses potential ecological risks.This study indicates that the source control of MPs and optimizing the process design of existing WWTPs are crucial for preventing and controlling MPs pollution.
基金supported by the National Natural Science Foundation of China(Nos.22276141 and 22236006)the Fundamental Research Funds for the Central Universities(No.22120220581).
文摘Antibiotic resistance genes(ARGs)are proposed as emerging environmental pollutants and pose potential threat to public health globally.The efficient removal of ARGs and prevention of their spread in the environment are of great concern.Wastewater treatment plants are among the hotspot of ARGs transmission,however,while both conventional and advanced water treatment processes cannot effectively remove ARGs.Therefore,employing advanced materials including Mxenes,black phosphorus and single atom catalysts in the elimination of pollutants such as ARGs has garnered attention.In this review,first of all,the characteristics of ARGs and environmental parameters,which include pH and ions that influences ARGs removal were elucidated.Secondly,different types of materials used to remove ARGs were summarized.The removalmechanisms of ARGsweremainly related to adsorption(active sites)and degradation(radical and non-radical way).Finally,the design strategies for materials employed in ARGs removal were proposed.This review improves our understanding of the important roles of the traditional and advanced materials in the management of ARGs pollution.
基金supported by the National Natural Science Foundation of China(No.52270078)the Fundamental Research Funds for the Central Universities(No.xzy022023039).
文摘Microbial fuel cells(MFCs)face significant challenges related to low power output,which severely limits their practical applications.Coupling MFC with other technologies and stacking MFCs are feasible solutions to enhance power output.In recent years,the coupling and stacking technology of MFCs has become a research hotspot in the field of environmental energy.This paper first outlines the basic configurations of MFCs and then analyzes the advantages and disadvantages of different setups in the context of coupling and stacking.Subsequently,it discusses in detail the coupling systems of MFC with other technologies,as well as several configurations of stacked MFCs and the phenomenon of voltage reversal.Based on these investigations,the paper proposes future research directions aimed at optimizing MFC performance,thereby enhancing their potential for energy recovery from wastewater and supporting the commercialization and scaling of MFC technology.
基金Projects(51104080,u1137601) supported by the National Natural Science Foundation of ChinaProject(2009CD027) supported by the Natural Science Foundation of Yunnan Province,ChinaProject(14118557) supported by the Personnel Training Foundation of Kunming University of Science and Technology,China
文摘Gas blowing is a valid method to remove the impurities from metallurgical grade silicon(MG-Si) melt.The thermodynamic behavior of impurities Fe,Al,Ca,Ti,Cu,C,B and P in MG-Si was studied in the process of O2 blowing.The removal efficiencies of impurities in MG-Si were investigated using O2 blowing in ladle.It is found that the removal efficiencies are higher than 90% for Ca and Al and nearly 50% for B and Ti.The morphology of inclusions was analyzed and the phases Al3Ni,NiSi2 and Al3Ni were confirmed in MG-Si by X-ray diffraction.It was found that SiB4 exists in Si?B binary system.The chemical composition of inclusions in MG-Si before and after refining was analyzed by SEM-EDS.It is found that the amount of white inclusion reduces for the removal of most Al and Ca in the forms of molten slag inclusion and the contents of Fe,Ni and Mn in inclusion increase for their inertia in silicon melt with O2 blowing.
基金Supported by the Fund for Independent Innovation of Agricultural Sciences in Jiangsu Province(CX(13)3073)Jiangsu Science and Technology Support Program(BE2014-342-1)~~
文摘[Objective] The study was conducted to optimize the operation parameters of water control equipment for deep-litter beddings. [Method] A four-factor three-level orthogonal design was adopted to optimize experimental temperature, stopping time of aeration, aeration time and aeration rate by 9 groups of experiments, so as to improve the water removal efficiency of adopted mixed and reduce operation energy consumption. [Result] The average water contents in the mixed bedding under 3 temperatures decreased by 4.58% ±2.91%, 13.17% ±3.77% and 10.8% ±7.72%, respectively; the highest water removal efficiency could be achieved under an experimental temperature at 45 ℃, stopping time of aeration of 15 min, aeration time of 7 min, and an aeration rate at 4 m^3/min, which formed the optimal factor combination mode of the operation parameter of the water control equipment; the effects of various experimental factors on water content in the bedding were in order of aeration ratetemperatureaeration timestopping time of aeration; and the effects of various experimental factors on water removal efficiency in the bedding were in order of temperatureaeration rateaeration timestopping time of aeration. [Conclusion] After the optimization of operation parameters of the water control equipment for the deep-litter bedding, water removal efficiency of the mixed bedding could be improved, and the operation energy consumption of the equipment could be reduced.