As an explosion control measure, rock dusting has been used in underground coal mines in many major coal producing countries with different standards. The effectiveness of the rock dust in reducing explosion intensity...As an explosion control measure, rock dusting has been used in underground coal mines in many major coal producing countries with different standards. The effectiveness of the rock dust in reducing explosion intensity has been proven by historic events and laboratory experiments. The main functions of rock dust in controlling mine explosions （i.e., isolator, physical heat sink and chemical energy absorber） have been quantitatively studied and results are presented in this paper.展开更多
This paper provides a calculation method for carbon activity in CO-H2-H2O atmosphere. The thermodynamic parameters （aC）gas （carbon activity in environment） of different compositions at any temperature can be obtai...This paper provides a calculation method for carbon activity in CO-H2-H2O atmosphere. The thermodynamic parameters （aC）gas （carbon activity in environment） of different compositions at any temperature can be obtained by △G^oT. A theoretical analysis has been conducted into the thermodynamic role of iron and the dependence of possible metal-dusting occurrence on temperature, gas composition and total pressure. In CO-H2-H2O gas mixtures, decreasing the molar fraction of H2O and increasing total pressure expands the temperature region for metal dusting. In CO-H2-H2O gas mixture of different compositions at any temperature and pressure for Fe, depending on relative values of （aC）gas, （aC）Fe3C/Fe and aC= 1, three zones were found to exist.展开更多
Firstly, physical and chemical properties of dust removed from BOF gas are analyzed, and then the cold banding technology of dust removed from BOF gas and its application are introduced. Tests have proved that using c...Firstly, physical and chemical properties of dust removed from BOF gas are analyzed, and then the cold banding technology of dust removed from BOF gas and its application are introduced. Tests have proved that using cooled agglomerated pellets made of the dust removed from BOF gas and small amounts of modified starch as a coolant and slagging agent in steel production can bring about considerable economic, social and environmental benefits.展开更多
In order to obtain appropriate spray pressure and enhance the spraying and dust removal efficiency, various factors including the dust characteristics, nozzle spraying angle, effective spraying range, water consumptio...In order to obtain appropriate spray pressure and enhance the spraying and dust removal efficiency, various factors including the dust characteristics, nozzle spraying angle, effective spraying range, water consumption and droplet size are taken into account. The dust characteristics from different mines and atomization parameters of different pressure nozzles were measured. It was found that the internal pressure of coal cutters and roadheaders should be kept at 2 MPa, which could ensure large droplet size, large spraying angle and low water consumption and hence realizing a large-area covering and capture for large particle dusts. However, the external spray pressure should be kept at 4 MPa for smaller droplet size and longer effective spraying range, leading to effective dust removal in the operator zone. The spray pressure of support moving, drawing opening, and stage loader on a fully mechanized caving face and stage loader on a fully mechanized driving face should be kept at 8 MPa, under which the nozzles have long effective spraying range, high water flow and small droplet size for the rapid capture of instantaneous, high-concentration and small size dust groups. From the applications on the caving and driving faces in the coal mines, it is indicated that the optimization of spray pressure in different spraying positions could effectively enhance dust removal efficiency. Selecting appropriate nozzles according to the dust characteristics at different positions is also favorable for dust removal efficiency. With the selected nozzles under optimal pressures, the removal rates of both total dust and respirable dust could reach over70%, showing a significant de-dusting effect.展开更多
Background:Recent advances in endoscopic technology have empowered urologists to treat most types of stones within the urinary tract effectively.Available treatments for ureteral stones using a laser lithotripter incl...Background:Recent advances in endoscopic technology have empowered urologists to treat most types of stones within the urinary tract effectively.Available treatments for ureteral stones using a laser lithotripter include fragmentation,the active removal of fragments with a basket,and dusting.To date,only a few prospective randomized studies have endorsed the use of stone dusting,fragmentation,and active removal for ureteric stones.Materials and methods:This randomized,prospective,comparative study was conducted in the Urology Department.Sixty patients with proximal ureteral stones from July 2019 to July 2020 were included and randomly divided into 2 groups using a random number generator program(version 2,2015).In Group 1,the stones were fragmented into dust(n=30),and in Group 2,lithotripsy produced extractable fragments(n=30).Results:In this study,the Ho:YAG laser was used to dust stones at low energy and high frequency(0.4-0.6 J and 20-30 Hz).Using the Ho:YAG laser set to high energy and low frequency(1.5-2 J and 8-10 Hz),stone fragmentation was achieved.Themean stone size was 1.63 cm in Group 1 and 1.69 cm in Group 2.The stone-free rates for the dusting and fragmentation groups were 96.6%and 86.6%,respectively.Meanwhile,the mean operative time was 87.6±33.6 minutes in the dusting group and 80.4±28.8 minutes in the fragmentation group.There were no postoperative complications with the dusting technique,compared with a 13.3%complication rate with the fragmentation technique.Conclusions:For proximal ureteral stones,the stone-free rates between the dusting and fragmentation procedures were comparable.Both techniques proved to be effective.展开更多
Powder dusting method is the most practically useful approach for latent fingerprint development in the crime scene. Herein, a general powder dusting method has been explored for latent fingerprint development based o...Powder dusting method is the most practically useful approach for latent fingerprint development in the crime scene. Herein, a general powder dusting method has been explored for latent fingerprint development based on aggregation-induced emission luminogens(AIEgens). A series of tetraphenylethene(TPE) derivatives with multiple diphenylamine(DPA), namely, TPE-DPA,TPE-2 DPA and TPE-4 DPA, were selected as candidates to dope with magnetic powders and applied for latent fingerprint development. After screening, the magnetic powder 3 doped with TPE-4 DPA proves to be the best, in terms of fluorescent intensity, resolution and adhesiveness. Afterwards, the magnetic powder 3 was applied for visualization of latent fingerprint on various smooth and porous substrates, including glass, stainless steel, leaf, ceram, plastic bag, lime wall, wood and paper money.Specific details, such as island, core, termination and bifurcation, can be clearly observed for the fluorescent fingerprint images.展开更多
Aiming at reducing the dust pollution during the tunneling process and improving the application efficiency of air curtain dust prevention technology,according to the changes of radial jet velocity(v_(r)),axial extrac...Aiming at reducing the dust pollution during the tunneling process and improving the application efficiency of air curtain dust prevention technology,according to the changes of radial jet velocity(v_(r)),axial extraction velocity(v_(e))and extraction distance(L)in the formation process of air curtain,the numerical simulation method was used to analyze the rules of airflow structure evolution and the diffusion characteristics of dust particles in fully mechanized excavation tunnel.The results indicate that as v_(r) and v_(e) increase,the migration path of the wall jet of the air curtain changes into an axial direction;as L decreases,the migration distance increases accordingly.These phenomena make the airflow distribution in the working face tends to be uniform.The dust diffusion distance reduces as well,wherein,the range of the discrete area of dust particles decreases sharply,until all dust particles are concentrated in the accumulation area.On this basis,the v_(r),v_(e) and L were optimized and applied in the 63_(up) 08 fully mechanized working face.By the application of the optimal parameters,the average dust removal efficiency at the driver’s position increased by 71%.The dust concentration was reduced and the working environment had been improved effectively.展开更多
Due to the presence of nitro groups, the dust generated during the production and utilization of energetic materials may potentially lead to dust explosion even under low-oxygen or anaerobic conditions.Considering the...Due to the presence of nitro groups, the dust generated during the production and utilization of energetic materials may potentially lead to dust explosion even under low-oxygen or anaerobic conditions.Considering the high energy density of energetic materials, dust explosion can cause serious production safety accidents. Therefore, it is necessary to understand the dust explosion characteristics of energetic materials and the mechanism of dust explosion. According to the literature review, among various influencing factors, the physical and chemical properties of dust are the decisive factors affecting the explosion characteristics of dust. In addition to experimental studies, numerical simulation is another important tool. However, it is subjected to certain limitations. Moreover, it is essential but challenging to fully understand the underlying mechanism. In addition, given the safety hazards posed by dust explosion, explosion suppression has attracted extensive attention for research. Depending on the medium used, there are different forms of suppression, including powder explosion suppression, water spray explosion suppression, inert gas explosion suppression, porous material explosion suppression, and vacuum chamber explosion suppression. As for the selection of explosion suppression agent, consideration must be given to the characteristics of the material. Furthermore, the above research has laid a foundation for discussing the future progress in studying dust explosion of energetic materials, with nano dust and the constraints of existing technology as the focal point.展开更多
The large amount of harmful particles in coal dust not only pollutes the production environment,affects the production efficiency and resource utilization of enterprises,but also poses a risk to human health.Effective...The large amount of harmful particles in coal dust not only pollutes the production environment,affects the production efficiency and resource utilization of enterprises,but also poses a risk to human health.Effectively controlling coal dust is of great significance to clean production.Water-based dust suppressants are extensively employed to mitigate coal dust.This paper provides a comprehensive review of the water-based dust suppression materials for coal dust control.Accord-ing to the difference of mechanism,the dust suppressants are divided into wetting type,hygroscopic coalescence type,cohesive agglomeration type,and composite type.The evaluation methods for dust suppressants key properties such as wettability,permeability,moisture absorption and water retention,and consolidation are summarized.The review results show that coal dust suppressants are no longer limited to a single dust suppression function.For example,it is necessary to develop multi-functional coal suppressants to meet the needs for synergistic suppression both coal dust and coal spon-taneous combustion.Driven by the concept of green,low-carbon and sustainable development,attention should be paid to the development of bio-based environmentally friendly coal dust suppressants.In addition,the evaluation method system for the key performance of water-based dust suppressants should also be improved,and further research is necessary.展开更多
Synthesis technology and properties of cordierite from solid waste resources/Tan Qitong,Zhao Huizhong,Yu Jun,Zhang Han,Tan Liqiang//Naihuo Cailiao.-2024,58(3):185 Abstract:To effectively utilize solid waste resources ...Synthesis technology and properties of cordierite from solid waste resources/Tan Qitong,Zhao Huizhong,Yu Jun,Zhang Han,Tan Liqiang//Naihuo Cailiao.-2024,58(3):185 Abstract:To effectively utilize solid waste resources and relieve resource constraints,cordierite refractory raw materials were prepared according to the chemical composition of cordierite,using 12 mass%fused magnesia dust powder,40 mass%fused corundum dust powder and 48 mass%quartz tailings as starting materials.展开更多
The occurrence of extreme weather events is becoming more frequent due to global climate change.A long-lasting dust outbreak in the spring of 2023 was triggered by Mongolia cyclones and cold fronts in the dust source ...The occurrence of extreme weather events is becoming more frequent due to global climate change.A long-lasting dust outbreak in the spring of 2023 was triggered by Mongolia cyclones and cold fronts in the dust source areas.In this study,we illustrate the spatial distribution,the transport path of the dust and its influence on the air quality of downstream cities utilizing ground-based and space-borne measurements.Results indicate a more complicated pollution,coexisting of polluted dust stage S1 and pure dust stage S2.In S1,the aerosol was characterized by a dual-layer vertical structure—high extinction coefficient of nearly 1.0 km^(−1)with a low particle depolarized ratio(PDR)of<0.1 under 500 m,and a small extinction coefficient of 0.3 km^(−1)with a high PDR of 0.15 above 500 m.Then the intrusion of the Mongolian cyclone carried new dust plumes on March 10,2023,suggesting the onset of pure dust period S2.The source transition was also confirmed by the MODIS,CALIPSO and Hysplit observations.The pure Asian dust evolved rapidly with one thickening layer and distributed homogeneously in the boundary layer.The PDR increased significantly to the peak of 0.35 and resulted in the peak PM10 value of>1300µg/m^(3).PM10 positively correlated with trace gases in S1 while varying inversely with the pollution gases in S2.The results help to shed light on the classification of different types of dust and also be useful in developing an effective strategy to forecast air pollution in downstream areas.展开更多
Silicomanganese dust contains large amounts of valuables,such as Si and Mn,which can be used as raw materials for the smelting of silicomanganese.However,the direct addition of dust to the submerged arc furnace can in...Silicomanganese dust contains large amounts of valuables,such as Si and Mn,which can be used as raw materials for the smelting of silicomanganese.However,the direct addition of dust to the submerged arc furnace can influence the permeability of burden due to the fine particle size of dust,which results in incomplete reduction reactions during the smelting process.In this paper,silicomanganese dust,graphite powder,and other additives were pressed to form carbon-containing dust briquettes,and the self-reduction process of the dust briquettes was investigated through the isothermal thermogravimetric method with different carbon–oxygen (C/O) molar ratios,contents of fluxing agents,and reduction temperatures.Various reduction kinetic models for dust briquettes at different temperatures were established.The results show that the reaction fraction of the dust briquettes was about 90%at a C/O molar ratio of 1.2 with optimal reduction efficiency.The addition of CaF_(2)contributed to the decrease in the melting point and viscosity of dust briquettes,which increased their reduction rate.As the reduction temperature increased,the reduction rate of dust briquettes increased.The reduction reaction rate of dust briquettes was controlled through gas-phase diffusion.Meanwhile,their reduction process was analyzed kinetically,with the reaction time of 5 min as the dividing line.The apparent activation energies for the two diffusion stages were 56.10 and 100.52 kJ/mol,respectively.The kinetic equations are expressed as[1-(1-f)^(1/3)]^(2)=0.69e^(-56100/(RT))t and [1-(1-f)^(1/3)]^(2)=2.06e^(-100520/(RT))t.展开更多
The effectiveness of fluopyram suspension concentrate against pine wilt disease(PWD)is limited by spraying efficiency and water dependence.A traditional dust formulation with strong dispersibility can overcome these s...The effectiveness of fluopyram suspension concentrate against pine wilt disease(PWD)is limited by spraying efficiency and water dependence.A traditional dust formulation with strong dispersibility can overcome these shortcomings.However,its efficacy against PWD remains uncertain.This study evaluated the translocation of fluopyram dust within tree tissues,soil and water degradation,and its effective control against PWD.Nursery tests showed effective prevention;field tests showed dust absorption and translocation into pine tissues.Thirty days following application,residual concentrations in soil were low at 0.09 mg kg^(−1);no detectable residues were found in water samples.Three years after applying fluopyram,its effectiveness increased to approximately 87%.Based on this study,fluopyram had a half-life of 346 d with persistence lasting up to three years.This provides valuable insight for managing PWD through dust applications.展开更多
The factors controlling dust activity and humidity in Central Asia and their relationships remain controversial,partly due to a lack of high-resolution geological records for the mid-to-late last glaciation.In this st...The factors controlling dust activity and humidity in Central Asia and their relationships remain controversial,partly due to a lack of high-resolution geological records for the mid-to-late last glaciation.In this study,we established an optically stimulated luminescence chronology for the QSHA profile in the Yili Basin,a region influenced by westerlies.Grain size and trace element data were used as paleoclimatic indicators.We investigated the relationships among Central Asian dust activity,humidity,and westerlies strength on orbital to millennial scale from 37.4 ka to 11.6 ka.Our study reveals that,on orbital timescales,humidity is positively correlated with westerlies strength which controlled by precession.Dust activity is controlled by Siberian High which was regulated by Northern Hemisphere high-latitude temperature.Their responses to low-latitude and high-latitude forcing mechanisms respectively and present an opposite relationship.On millennial timescales,humidity and westerlies strength are positively correlated.During Marine Isotope Stage(MIS)2,humidity and dust activity show synchronous fluctuations,while during MIS 3,they exhibit an inverse relationship.Westerlies strength regulated humidity,which subsequently controlled glacial activity in the Tianshan Mountains,influencing dust activity in Central Asia.Additionally,the QSHA profile recorded seven Dansgaard-Oeschger(D-O)events on millennial timescales,indicating a potential link between Central Asian dust activity and high-latitude temperature variations in the Northern Hemisphere.Our findings provide new insights into dust and humidity interaction during the last glaciation periods in Central Asia and contribute to understanding global dust and hydrological cycles.展开更多
Soil organic carbon(SOC)and total nitrogen(TN)play an important role in the global carbon and nitrogen cycles.Soil aggregates are critical reservoir of SOC and TN.Therefore,in areas with severe wind erosion,the change...Soil organic carbon(SOC)and total nitrogen(TN)play an important role in the global carbon and nitrogen cycles.Soil aggregates are critical reservoir of SOC and TN.Therefore,in areas with severe wind erosion,the changes in the accumulation of SOC,TN,clay,silt,and sand contents within different dry aggregate size fractions can offer crucial insights into soil conservation by the control of wind erosion.In this study,surface soil samples(0–5 cm depth)were collected from farmland and grassland in the Bashang region of northern China in 2020.The bulk soil and aggregate size fractions were used to determine the concentrations of SOC,TN,clay,silt,and sand.The results showed that:(1)farmland had lower SOC and higher TN than grassland;(2)SOC in the aggregates of farmland decreased with increasing aggregate size(P<0.010),while SOC in the aggregates of grassland increased with increasing aggregate size(P<0.010),and nonsignificant variation of TN and clay was observed among different aggregate sizes;(3)the mean of aggregate silt significantly decreased with increasing aggregate size and the mean of aggregate sand increased with increasing aggregate size(P<0.001);(4)no correlations between sand or silt of aggregate and TN or texture of bulk soil was found;and(5)SOC in bulk soil was correlated with those in different aggregate sizes,and was also affected by the texture of bulk soil(P<0.010).This study highlights the role of dry soil aggregate size in the redistribution of SOC,TN,clay,silt,and sand contents under different land uses,thereby facilitating the understanding of the process of wind erosion induced SOC,TN,and mineral dust emission.展开更多
Resource utilization of metallurgical solid waste is vital for the sustainable development of the steel industry in the context of“dual carbon.”The calcification-carbothermal reduction method was employed to extract...Resource utilization of metallurgical solid waste is vital for the sustainable development of the steel industry in the context of“dual carbon.”The calcification-carbothermal reduction method was employed to extract zinc and iron from electric furnace dust effectively.In this process,calcium oxide reacts with zinc ferrite to form dicalcium ferrite and zinc oxide,which further promotes the effective separation of zinc and iron.However,the addition of pure calcium oxide increases production costs for steel companies.Herein,a new process for dust removal and zinc recovery in electric furnaces has been developed,using electric furnace slag as a calcium agent and mineral trough ash as a reducing agent.Large amounts of dicalcium ferrate phases were detected in the carbothermal reduction products by steel slag synergistic calcification.The reaction mechanism was determined as ZnFe_(2)O_(4)+CaO→Ca_(2)Fe_(2)O_(5)+ZnO→Ca_(2)Fe_(2)O_(5)+Zn(g).Such a two-step reaction path indicated that steel slag can effectively promote the reduction and volatilization of zinc.The experimental optimal roasting parameters were determined as roasting temperature of 1150℃,roasting time of 45 min,calcium to zinc molar ratio of 1.1,and carbon to oxygen molar ratio of 0.8.The mass percentage of added steel slag was recorded as 21.83%,while that of mineral trough ash was 21.85%.Under these conditions,the zinc removal rate above 99%and the metallization rate of pellets of about 75.31%were achieved.Overall,the proposed method looks promising for future efficient separation of zinc and iron in industrial steel slag.展开更多
To explore the multicenter characteristics of endocrine-like phthalate esters(PAEs)in household dust and propose effective control strategies for global indoor public health.An on-site observational investigation was ...To explore the multicenter characteristics of endocrine-like phthalate esters(PAEs)in household dust and propose effective control strategies for global indoor public health.An on-site observational investigation was conducted in nine Chinese cities from 2018 to 2019.A total of 246 household dust sampleswere collected and analyzed for ten PAE congeners using Gas Chromatography-Mass Spectrometry(GC-MS).Questionnaires were used to gather information on building conditions,indoor behaviors,and ventilation habits.In residential dust from the nine cities,the total concentrations of the ten PAE congeners(PAEs)ranged from 0.921 to 29097.297μg/g.Dicyclohexyl phthalate(DCHP)and di(2-ethylhexyl)phthalate(DEHP)were the dominant congeners inPAEs.Childhood exposure to PAEs through dust ingestion was four orders of magnitude higher than through inhalation,with a carcinogenic risk of 5.47×10^(−6) for DEHP exposure in household dust.HigherPAEs concentrations were associated with higher temperature,double glazing,wall paint usage,television and computer use,and indoor plant growth.This multicenter on-site investigation confirmed PAE pollution characteristics and uncovered the inacceptable risk of daily DEHP exposure in household dust under real living conditions.Effective mitigation measures based on household-related information,residential characteristics,decoration materials,and lifestyle should be taken to build a healthy household environment.展开更多
Arid West Asia(AWA)is a critical hub of the Silk Road and one of the primary dust source regions in the Northern Hemisphere.Dust storms in AWA emitting substantial dust particles into the atmosphere,significantly infl...Arid West Asia(AWA)is a critical hub of the Silk Road and one of the primary dust source regions in the Northern Hemisphere.Dust storms in AWA emitting substantial dust particles into the atmosphere,significantly influencing air quality,climate change and marine productivity.However,the variability of dust storm activity in this region during the Holocene,particularly its links to vegetation and hydroclimatic changes,remains debated,hindering our understanding of the interconnected dynamics between climate change and surface environments.This study reconstructs dust storm variations in AWA over the past 9000 years using geochemical analyses(trace elements,Sr-Nd isotopes)from a well-dated,high-resolution sediment core from the Almalou Peatland,located on the western Iranian Plateau.Our results reveal a decline in dust storm frequency from the early to mid-Holocene,a minimum occurrence during the mid-Holocene,and a significant increase in the late Holocene.Provenance analysis indicates that the primary dust sources were the arid regions of Mesopotamia,located upwind of the study area.A comparison with proxy records and paleoclimate models suggests an inverse relationship between dust storm activity and regional hydroclimatic and vegetation changes,along with a positive correlation with wind speeds.The concentration of dust storms during the wetter month of May highlights wind speed as a more critical driving factor.Moreover,given the dominant influence of the subtropical high on hydroclimatic conditions and wind speeds in AWA,we propose that this system is the key regulator of regional dust storm dynamics.Our findings provide new insights into the drivers of dust storm activity in AWA and hold implications for developing targeted dust storm management strategies.展开更多
The availability of large data sets containing stellar parameters,distances,and extinctions for stars in the Milky Way,particularly within the Galactic disk,is essential for advancing our understanding of the Galaxy’...The availability of large data sets containing stellar parameters,distances,and extinctions for stars in the Milky Way,particularly within the Galactic disk,is essential for advancing our understanding of the Galaxy’s stellar populations,structure,kinematics,and chemical evolution.In this study,we present a catalog of stellar parameters,including effective temperature (T_(eff)),metallicity ([Fe/H]),absolute magnitudes (M_(G)),distances (d),and reddening values (E(G_(BP)-G_(RP))),for a sample of 141 million stars from the SkyMapper Southern Survey.These parameters are derived using the SPar algorithm,which employs a fitting procedure to match multi-band photometric observations and estimate the stellar properties (T_(eff),[Fe/H],M_(G),d,and E(G_(BP)-G_(RP))) on an individual star basis,following the methodology outlined in our previous work.This study successfully determines stellar parameters and extinction values simultaneously for stars located in high and low Galactic latitudes.The resulting stellar parameters and extinction values are in good agreement with results from other studies,demonstrating the robustness of our method.We derive a temperature dispersion of 195 K and a metallicity dispersion of 0.31 dex when comparing our results with spectroscopic data.The catalog produced in this work provides a valuable resource for future research on the Galactic metallicity distribution function,the structure of the Galaxy,threedimensional extinction mapping,and other related astrophysical topics.展开更多
The Ni-ZnFe_(2)O_(4)(NixZn_(1-x)Fe_(2)O_(4),x=0.4-0.7)spinel was synthesized using Zn2+extracted from electric arc furnace dust(EAFD),nickel chloride hexahydrate,and Fe^(3+)extracted from iron scale as raw materials.T...The Ni-ZnFe_(2)O_(4)(NixZn_(1-x)Fe_(2)O_(4),x=0.4-0.7)spinel was synthesized using Zn2+extracted from electric arc furnace dust(EAFD),nickel chloride hexahydrate,and Fe^(3+)extracted from iron scale as raw materials.The zinc was selectively extracted from EAFD using CaO roasting followed by NH_(4)Cl solution leaching.The ferric ion was leached from iron scale using HCl solution as acid lixiviant.The experimental results demonstrate a high level of efficiency in the extraction of zinc,with a rate of 97.5%,and the leaching rate of ferric ion is 96.89%.The composition of the leaching solution is primary zinc and iron with low calcium,which is beneficial to the preparation of spinel ferrite.The influence of Ni content(x)and calcination temperature on the synthesis and magnetic properties of NixZn_(1-x)Fe_(2)O_(4)compounds was investigated by X-ray diffraction,scanning electron microscopy,and vibrating sample magnetometry.The results revealed that both Ni content and calcination temperature significantly affect the synthesis and magnetic properties of spinel NixZn_(1-x)Fe_(2)O_(4).Under the conditions of Ni content set at x=0.6,calcination temperature of 1100℃,and a duration of 2 h,a spinel NixZn_(1-x)Fe_(2)O_(4)with high saturation magnetization(Ms=65.7 A m2 kg-1)and low coercivity(Hc=0.056 A m^(-1))was obtained.展开更多
文摘As an explosion control measure, rock dusting has been used in underground coal mines in many major coal producing countries with different standards. The effectiveness of the rock dust in reducing explosion intensity has been proven by historic events and laboratory experiments. The main functions of rock dust in controlling mine explosions （i.e., isolator, physical heat sink and chemical energy absorber） have been quantitatively studied and results are presented in this paper.
基金supported by National Natural Science Foundation of China (NO.50675096)
文摘This paper provides a calculation method for carbon activity in CO-H2-H2O atmosphere. The thermodynamic parameters （aC）gas （carbon activity in environment） of different compositions at any temperature can be obtained by △G^oT. A theoretical analysis has been conducted into the thermodynamic role of iron and the dependence of possible metal-dusting occurrence on temperature, gas composition and total pressure. In CO-H2-H2O gas mixtures, decreasing the molar fraction of H2O and increasing total pressure expands the temperature region for metal dusting. In CO-H2-H2O gas mixture of different compositions at any temperature and pressure for Fe, depending on relative values of （aC）gas, （aC）Fe3C/Fe and aC= 1, three zones were found to exist.
文摘Firstly, physical and chemical properties of dust removed from BOF gas are analyzed, and then the cold banding technology of dust removed from BOF gas and its application are introduced. Tests have proved that using cooled agglomerated pellets made of the dust removed from BOF gas and small amounts of modified starch as a coolant and slagging agent in steel production can bring about considerable economic, social and environmental benefits.
基金support from the National Natural Science Foundation of China (Nos.U1261205, 51474139 and 51204103)the Science and Technology Development Plan of Shandong Province (No.2013GSF12004)the Excellent Young Scientific Talents Project of Shandong University of Science and Technology (No.2014JQJH106)
文摘In order to obtain appropriate spray pressure and enhance the spraying and dust removal efficiency, various factors including the dust characteristics, nozzle spraying angle, effective spraying range, water consumption and droplet size are taken into account. The dust characteristics from different mines and atomization parameters of different pressure nozzles were measured. It was found that the internal pressure of coal cutters and roadheaders should be kept at 2 MPa, which could ensure large droplet size, large spraying angle and low water consumption and hence realizing a large-area covering and capture for large particle dusts. However, the external spray pressure should be kept at 4 MPa for smaller droplet size and longer effective spraying range, leading to effective dust removal in the operator zone. The spray pressure of support moving, drawing opening, and stage loader on a fully mechanized caving face and stage loader on a fully mechanized driving face should be kept at 8 MPa, under which the nozzles have long effective spraying range, high water flow and small droplet size for the rapid capture of instantaneous, high-concentration and small size dust groups. From the applications on the caving and driving faces in the coal mines, it is indicated that the optimization of spray pressure in different spraying positions could effectively enhance dust removal efficiency. Selecting appropriate nozzles according to the dust characteristics at different positions is also favorable for dust removal efficiency. With the selected nozzles under optimal pressures, the removal rates of both total dust and respirable dust could reach over70%, showing a significant de-dusting effect.
文摘Background:Recent advances in endoscopic technology have empowered urologists to treat most types of stones within the urinary tract effectively.Available treatments for ureteral stones using a laser lithotripter include fragmentation,the active removal of fragments with a basket,and dusting.To date,only a few prospective randomized studies have endorsed the use of stone dusting,fragmentation,and active removal for ureteric stones.Materials and methods:This randomized,prospective,comparative study was conducted in the Urology Department.Sixty patients with proximal ureteral stones from July 2019 to July 2020 were included and randomly divided into 2 groups using a random number generator program(version 2,2015).In Group 1,the stones were fragmented into dust(n=30),and in Group 2,lithotripsy produced extractable fragments(n=30).Results:In this study,the Ho:YAG laser was used to dust stones at low energy and high frequency(0.4-0.6 J and 20-30 Hz).Using the Ho:YAG laser set to high energy and low frequency(1.5-2 J and 8-10 Hz),stone fragmentation was achieved.Themean stone size was 1.63 cm in Group 1 and 1.69 cm in Group 2.The stone-free rates for the dusting and fragmentation groups were 96.6%and 86.6%,respectively.Meanwhile,the mean operative time was 87.6±33.6 minutes in the dusting group and 80.4±28.8 minutes in the fragmentation group.There were no postoperative complications with the dusting technique,compared with a 13.3%complication rate with the fragmentation technique.Conclusions:For proximal ureteral stones,the stone-free rates between the dusting and fragmentation procedures were comparable.Both techniques proved to be effective.
基金supported by the Opening Project Fund of Shanghai Key Laboratory of Criminal Scene Evidence (201123417049)the Academician Foundation of the Ministry of Public Security of China (2011-23214203, 23215243, 23317015)+4 种基金Program for Young Innovative Research Team in China University of Political Science and Law (18CXTD09, 16CXTD05)the National Natural Science Foundation of China (21788102)the Research Grants Council of Hong Kong (16308116, C2014-15G, A-HKUST605/16, C6009-17G)the Nissan Chemical Industries Ltd., the AIEgen Biotech Co. Ltd., the Innovation and Technology Commission (ITC-CNERC14SC01)the Science and Technology Plan of Shenzhen (JCY20160229205601482)
文摘Powder dusting method is the most practically useful approach for latent fingerprint development in the crime scene. Herein, a general powder dusting method has been explored for latent fingerprint development based on aggregation-induced emission luminogens(AIEgens). A series of tetraphenylethene(TPE) derivatives with multiple diphenylamine(DPA), namely, TPE-DPA,TPE-2 DPA and TPE-4 DPA, were selected as candidates to dope with magnetic powders and applied for latent fingerprint development. After screening, the magnetic powder 3 doped with TPE-4 DPA proves to be the best, in terms of fluorescent intensity, resolution and adhesiveness. Afterwards, the magnetic powder 3 was applied for visualization of latent fingerprint on various smooth and porous substrates, including glass, stainless steel, leaf, ceram, plastic bag, lime wall, wood and paper money.Specific details, such as island, core, termination and bifurcation, can be clearly observed for the fluorescent fingerprint images.
基金financially supported by the Natural Science Foundation of Shandong Province(ZR2020QE124,ZR2023ME031 and ZR2023ME012)Innovation Achievement Cultivation Project of Qingdao University of Technology(CLZ2022-002)National Natural Science Foundation of China(52404222 and 52374209).
文摘Aiming at reducing the dust pollution during the tunneling process and improving the application efficiency of air curtain dust prevention technology,according to the changes of radial jet velocity(v_(r)),axial extraction velocity(v_(e))and extraction distance(L)in the formation process of air curtain,the numerical simulation method was used to analyze the rules of airflow structure evolution and the diffusion characteristics of dust particles in fully mechanized excavation tunnel.The results indicate that as v_(r) and v_(e) increase,the migration path of the wall jet of the air curtain changes into an axial direction;as L decreases,the migration distance increases accordingly.These phenomena make the airflow distribution in the working face tends to be uniform.The dust diffusion distance reduces as well,wherein,the range of the discrete area of dust particles decreases sharply,until all dust particles are concentrated in the accumulation area.On this basis,the v_(r),v_(e) and L were optimized and applied in the 63_(up) 08 fully mechanized working face.By the application of the optimal parameters,the average dust removal efficiency at the driver’s position increased by 71%.The dust concentration was reduced and the working environment had been improved effectively.
基金the financial support of the Shanxi Fire & Explosion-Proofing Safety Engineering and Technology Research Center, North University of China。
文摘Due to the presence of nitro groups, the dust generated during the production and utilization of energetic materials may potentially lead to dust explosion even under low-oxygen or anaerobic conditions.Considering the high energy density of energetic materials, dust explosion can cause serious production safety accidents. Therefore, it is necessary to understand the dust explosion characteristics of energetic materials and the mechanism of dust explosion. According to the literature review, among various influencing factors, the physical and chemical properties of dust are the decisive factors affecting the explosion characteristics of dust. In addition to experimental studies, numerical simulation is another important tool. However, it is subjected to certain limitations. Moreover, it is essential but challenging to fully understand the underlying mechanism. In addition, given the safety hazards posed by dust explosion, explosion suppression has attracted extensive attention for research. Depending on the medium used, there are different forms of suppression, including powder explosion suppression, water spray explosion suppression, inert gas explosion suppression, porous material explosion suppression, and vacuum chamber explosion suppression. As for the selection of explosion suppression agent, consideration must be given to the characteristics of the material. Furthermore, the above research has laid a foundation for discussing the future progress in studying dust explosion of energetic materials, with nano dust and the constraints of existing technology as the focal point.
基金supported by the National Natural Science Foundation of China(52474226,52322404)Basic scientific research projects in higher education institutions of Liaoning Province(JYTZD2023079)。
文摘The large amount of harmful particles in coal dust not only pollutes the production environment,affects the production efficiency and resource utilization of enterprises,but also poses a risk to human health.Effectively controlling coal dust is of great significance to clean production.Water-based dust suppressants are extensively employed to mitigate coal dust.This paper provides a comprehensive review of the water-based dust suppression materials for coal dust control.Accord-ing to the difference of mechanism,the dust suppressants are divided into wetting type,hygroscopic coalescence type,cohesive agglomeration type,and composite type.The evaluation methods for dust suppressants key properties such as wettability,permeability,moisture absorption and water retention,and consolidation are summarized.The review results show that coal dust suppressants are no longer limited to a single dust suppression function.For example,it is necessary to develop multi-functional coal suppressants to meet the needs for synergistic suppression both coal dust and coal spon-taneous combustion.Driven by the concept of green,low-carbon and sustainable development,attention should be paid to the development of bio-based environmentally friendly coal dust suppressants.In addition,the evaluation method system for the key performance of water-based dust suppressants should also be improved,and further research is necessary.
文摘Synthesis technology and properties of cordierite from solid waste resources/Tan Qitong,Zhao Huizhong,Yu Jun,Zhang Han,Tan Liqiang//Naihuo Cailiao.-2024,58(3):185 Abstract:To effectively utilize solid waste resources and relieve resource constraints,cordierite refractory raw materials were prepared according to the chemical composition of cordierite,using 12 mass%fused magnesia dust powder,40 mass%fused corundum dust powder and 48 mass%quartz tailings as starting materials.
基金supported by the Innovation and Development Special Project of China Meteorological Administration(Nos.CXFZ2024J011 and CXFZ2024J057)the Key Lab.of Environmental Optics and Technology,CAS(No.2005DP173065-2021-07).
文摘The occurrence of extreme weather events is becoming more frequent due to global climate change.A long-lasting dust outbreak in the spring of 2023 was triggered by Mongolia cyclones and cold fronts in the dust source areas.In this study,we illustrate the spatial distribution,the transport path of the dust and its influence on the air quality of downstream cities utilizing ground-based and space-borne measurements.Results indicate a more complicated pollution,coexisting of polluted dust stage S1 and pure dust stage S2.In S1,the aerosol was characterized by a dual-layer vertical structure—high extinction coefficient of nearly 1.0 km^(−1)with a low particle depolarized ratio(PDR)of<0.1 under 500 m,and a small extinction coefficient of 0.3 km^(−1)with a high PDR of 0.15 above 500 m.Then the intrusion of the Mongolian cyclone carried new dust plumes on March 10,2023,suggesting the onset of pure dust period S2.The source transition was also confirmed by the MODIS,CALIPSO and Hysplit observations.The pure Asian dust evolved rapidly with one thickening layer and distributed homogeneously in the boundary layer.The PDR increased significantly to the peak of 0.35 and resulted in the peak PM10 value of>1300µg/m^(3).PM10 positively correlated with trace gases in S1 while varying inversely with the pollution gases in S2.The results help to shed light on the classification of different types of dust and also be useful in developing an effective strategy to forecast air pollution in downstream areas.
基金financially supported by the Hubei Provincial Key Laboratory for New Processes of Ironmaking and Steelmaking (No. KF-20-3)Shandong Postdoctoral Science Foundation, China (No. SDCX-ZG-202301014)。
文摘Silicomanganese dust contains large amounts of valuables,such as Si and Mn,which can be used as raw materials for the smelting of silicomanganese.However,the direct addition of dust to the submerged arc furnace can influence the permeability of burden due to the fine particle size of dust,which results in incomplete reduction reactions during the smelting process.In this paper,silicomanganese dust,graphite powder,and other additives were pressed to form carbon-containing dust briquettes,and the self-reduction process of the dust briquettes was investigated through the isothermal thermogravimetric method with different carbon–oxygen (C/O) molar ratios,contents of fluxing agents,and reduction temperatures.Various reduction kinetic models for dust briquettes at different temperatures were established.The results show that the reaction fraction of the dust briquettes was about 90%at a C/O molar ratio of 1.2 with optimal reduction efficiency.The addition of CaF_(2)contributed to the decrease in the melting point and viscosity of dust briquettes,which increased their reduction rate.As the reduction temperature increased,the reduction rate of dust briquettes increased.The reduction reaction rate of dust briquettes was controlled through gas-phase diffusion.Meanwhile,their reduction process was analyzed kinetically,with the reaction time of 5 min as the dividing line.The apparent activation energies for the two diffusion stages were 56.10 and 100.52 kJ/mol,respectively.The kinetic equations are expressed as[1-(1-f)^(1/3)]^(2)=0.69e^(-56100/(RT))t and [1-(1-f)^(1/3)]^(2)=2.06e^(-100520/(RT))t.
基金supported by grants from the National Key R&D Program of China(grant number 2021YFD1400900)the National Natural Science Foundation of China(grant numbers U1905201,32171805)+6 种基金the Forestry Key Program of Science and Technology in Fujian Province(grant number 2021FKJ03)the Natural Science Foundation of Fujian Province,China(grant number 2021J01056)the Forestry Programs of Science and Technology in Fujian Province[grant number Mincaizhi(2020)601]the Science and Technology Program of Fujian Province(grant number 2018N5002)the Forestry Science Research Project of Fujian Forestry Department[grant number Minlinke(2017)03]the National Major Emergency Science and Technology Program of China(grant number ZD202001)the Forestry Peak Discipline Construction Project of Fujian Agriculture and Forestry University(grant numbers 72202200205,71201800720).
文摘The effectiveness of fluopyram suspension concentrate against pine wilt disease(PWD)is limited by spraying efficiency and water dependence.A traditional dust formulation with strong dispersibility can overcome these shortcomings.However,its efficacy against PWD remains uncertain.This study evaluated the translocation of fluopyram dust within tree tissues,soil and water degradation,and its effective control against PWD.Nursery tests showed effective prevention;field tests showed dust absorption and translocation into pine tissues.Thirty days following application,residual concentrations in soil were low at 0.09 mg kg^(−1);no detectable residues were found in water samples.Three years after applying fluopyram,its effectiveness increased to approximately 87%.Based on this study,fluopyram had a half-life of 346 d with persistence lasting up to three years.This provides valuable insight for managing PWD through dust applications.
基金supported by the Natural Science Foundation of China(Grant Nos.42372220,42172207)the Youth Innovation Promotion Association Chinese Academy of Sciences(Grant No.Y2022102)+1 种基金the Science and Technology Innovation Project of Laoshan Laboratory(Grant No.LSKJ202203300)the International Partnership Program of the Chinese Academy of Sciences.
文摘The factors controlling dust activity and humidity in Central Asia and their relationships remain controversial,partly due to a lack of high-resolution geological records for the mid-to-late last glaciation.In this study,we established an optically stimulated luminescence chronology for the QSHA profile in the Yili Basin,a region influenced by westerlies.Grain size and trace element data were used as paleoclimatic indicators.We investigated the relationships among Central Asian dust activity,humidity,and westerlies strength on orbital to millennial scale from 37.4 ka to 11.6 ka.Our study reveals that,on orbital timescales,humidity is positively correlated with westerlies strength which controlled by precession.Dust activity is controlled by Siberian High which was regulated by Northern Hemisphere high-latitude temperature.Their responses to low-latitude and high-latitude forcing mechanisms respectively and present an opposite relationship.On millennial timescales,humidity and westerlies strength are positively correlated.During Marine Isotope Stage(MIS)2,humidity and dust activity show synchronous fluctuations,while during MIS 3,they exhibit an inverse relationship.Westerlies strength regulated humidity,which subsequently controlled glacial activity in the Tianshan Mountains,influencing dust activity in Central Asia.Additionally,the QSHA profile recorded seven Dansgaard-Oeschger(D-O)events on millennial timescales,indicating a potential link between Central Asian dust activity and high-latitude temperature variations in the Northern Hemisphere.Our findings provide new insights into dust and humidity interaction during the last glaciation periods in Central Asia and contribute to understanding global dust and hydrological cycles.
基金supported by the National Natural Science Foundation of China(4227100242201002)+2 种基金the Foundation of Central Guidance for Local Scientific and Technological Development(246Z3705G)the Water Conservancy Science and Technology Plan Project of Hebei Province(2023-64)the Hebei Natural Science Foundation(D2021205013).
文摘Soil organic carbon(SOC)and total nitrogen(TN)play an important role in the global carbon and nitrogen cycles.Soil aggregates are critical reservoir of SOC and TN.Therefore,in areas with severe wind erosion,the changes in the accumulation of SOC,TN,clay,silt,and sand contents within different dry aggregate size fractions can offer crucial insights into soil conservation by the control of wind erosion.In this study,surface soil samples(0–5 cm depth)were collected from farmland and grassland in the Bashang region of northern China in 2020.The bulk soil and aggregate size fractions were used to determine the concentrations of SOC,TN,clay,silt,and sand.The results showed that:(1)farmland had lower SOC and higher TN than grassland;(2)SOC in the aggregates of farmland decreased with increasing aggregate size(P<0.010),while SOC in the aggregates of grassland increased with increasing aggregate size(P<0.010),and nonsignificant variation of TN and clay was observed among different aggregate sizes;(3)the mean of aggregate silt significantly decreased with increasing aggregate size and the mean of aggregate sand increased with increasing aggregate size(P<0.001);(4)no correlations between sand or silt of aggregate and TN or texture of bulk soil was found;and(5)SOC in bulk soil was correlated with those in different aggregate sizes,and was also affected by the texture of bulk soil(P<0.010).This study highlights the role of dry soil aggregate size in the redistribution of SOC,TN,clay,silt,and sand contents under different land uses,thereby facilitating the understanding of the process of wind erosion induced SOC,TN,and mineral dust emission.
基金the support from Graduate Student Scientific Research Innovation Projects in Jiangsu Province(KYCX22_3804)Natural Science Foundation of Jiangsu Province(No.BK20210888).
文摘Resource utilization of metallurgical solid waste is vital for the sustainable development of the steel industry in the context of“dual carbon.”The calcification-carbothermal reduction method was employed to extract zinc and iron from electric furnace dust effectively.In this process,calcium oxide reacts with zinc ferrite to form dicalcium ferrite and zinc oxide,which further promotes the effective separation of zinc and iron.However,the addition of pure calcium oxide increases production costs for steel companies.Herein,a new process for dust removal and zinc recovery in electric furnaces has been developed,using electric furnace slag as a calcium agent and mineral trough ash as a reducing agent.Large amounts of dicalcium ferrate phases were detected in the carbothermal reduction products by steel slag synergistic calcification.The reaction mechanism was determined as ZnFe_(2)O_(4)+CaO→Ca_(2)Fe_(2)O_(5)+ZnO→Ca_(2)Fe_(2)O_(5)+Zn(g).Such a two-step reaction path indicated that steel slag can effectively promote the reduction and volatilization of zinc.The experimental optimal roasting parameters were determined as roasting temperature of 1150℃,roasting time of 45 min,calcium to zinc molar ratio of 1.1,and carbon to oxygen molar ratio of 0.8.The mass percentage of added steel slag was recorded as 21.83%,while that of mineral trough ash was 21.85%.Under these conditions,the zinc removal rate above 99%and the metallization rate of pellets of about 75.31%were achieved.Overall,the proposed method looks promising for future efficient separation of zinc and iron in industrial steel slag.
基金supported by the National Natural Science Foundation of China(No.21976169)the National Key Research and Development Program of China(No.2022YFC3702800).
文摘To explore the multicenter characteristics of endocrine-like phthalate esters(PAEs)in household dust and propose effective control strategies for global indoor public health.An on-site observational investigation was conducted in nine Chinese cities from 2018 to 2019.A total of 246 household dust sampleswere collected and analyzed for ten PAE congeners using Gas Chromatography-Mass Spectrometry(GC-MS).Questionnaires were used to gather information on building conditions,indoor behaviors,and ventilation habits.In residential dust from the nine cities,the total concentrations of the ten PAE congeners(PAEs)ranged from 0.921 to 29097.297μg/g.Dicyclohexyl phthalate(DCHP)and di(2-ethylhexyl)phthalate(DEHP)were the dominant congeners inPAEs.Childhood exposure to PAEs through dust ingestion was four orders of magnitude higher than through inhalation,with a carcinogenic risk of 5.47×10^(−6) for DEHP exposure in household dust.HigherPAEs concentrations were associated with higher temperature,double glazing,wall paint usage,television and computer use,and indoor plant growth.This multicenter on-site investigation confirmed PAE pollution characteristics and uncovered the inacceptable risk of daily DEHP exposure in household dust under real living conditions.Effective mitigation measures based on household-related information,residential characteristics,decoration materials,and lifestyle should be taken to build a healthy household environment.
基金National Natural Science Foundation of China,No.42201170Young Elite Scientists Sponsorship Program by CAST,No.2022QNRC001。
文摘Arid West Asia(AWA)is a critical hub of the Silk Road and one of the primary dust source regions in the Northern Hemisphere.Dust storms in AWA emitting substantial dust particles into the atmosphere,significantly influencing air quality,climate change and marine productivity.However,the variability of dust storm activity in this region during the Holocene,particularly its links to vegetation and hydroclimatic changes,remains debated,hindering our understanding of the interconnected dynamics between climate change and surface environments.This study reconstructs dust storm variations in AWA over the past 9000 years using geochemical analyses(trace elements,Sr-Nd isotopes)from a well-dated,high-resolution sediment core from the Almalou Peatland,located on the western Iranian Plateau.Our results reveal a decline in dust storm frequency from the early to mid-Holocene,a minimum occurrence during the mid-Holocene,and a significant increase in the late Holocene.Provenance analysis indicates that the primary dust sources were the arid regions of Mesopotamia,located upwind of the study area.A comparison with proxy records and paleoclimate models suggests an inverse relationship between dust storm activity and regional hydroclimatic and vegetation changes,along with a positive correlation with wind speeds.The concentration of dust storms during the wetter month of May highlights wind speed as a more critical driving factor.Moreover,given the dominant influence of the subtropical high on hydroclimatic conditions and wind speeds in AWA,we propose that this system is the key regulator of regional dust storm dynamics.Our findings provide new insights into the drivers of dust storm activity in AWA and hold implications for developing targeted dust storm management strategies.
基金supported by the National Natural Science Foundation of China12203016,12173034,12322304 and 12173013Natural Science Foundation of Hebei Province No.A2022205018,A2021205006,226Z7604G+4 种基金Yunnan University grant No.C619300A034Science Foundation of Hebei Normal University No.L2022B33.W.Y.Cacknowledges the science research grants from the China Manned Space Projectthe support of Physics Postdoctoral Research Station at Hebei Normal Universitythe science research grants from the China Manned Space Project with NOs.CMS-CSST-2021-A09,CMS-CSST-2021-A08 and CMS-CSST-2021-B03。
文摘The availability of large data sets containing stellar parameters,distances,and extinctions for stars in the Milky Way,particularly within the Galactic disk,is essential for advancing our understanding of the Galaxy’s stellar populations,structure,kinematics,and chemical evolution.In this study,we present a catalog of stellar parameters,including effective temperature (T_(eff)),metallicity ([Fe/H]),absolute magnitudes (M_(G)),distances (d),and reddening values (E(G_(BP)-G_(RP))),for a sample of 141 million stars from the SkyMapper Southern Survey.These parameters are derived using the SPar algorithm,which employs a fitting procedure to match multi-band photometric observations and estimate the stellar properties (T_(eff),[Fe/H],M_(G),d,and E(G_(BP)-G_(RP))) on an individual star basis,following the methodology outlined in our previous work.This study successfully determines stellar parameters and extinction values simultaneously for stars located in high and low Galactic latitudes.The resulting stellar parameters and extinction values are in good agreement with results from other studies,demonstrating the robustness of our method.We derive a temperature dispersion of 195 K and a metallicity dispersion of 0.31 dex when comparing our results with spectroscopic data.The catalog produced in this work provides a valuable resource for future research on the Galactic metallicity distribution function,the structure of the Galaxy,threedimensional extinction mapping,and other related astrophysical topics.
基金supported by the National Natural Science Foundation of China(No.52374344).
文摘The Ni-ZnFe_(2)O_(4)(NixZn_(1-x)Fe_(2)O_(4),x=0.4-0.7)spinel was synthesized using Zn2+extracted from electric arc furnace dust(EAFD),nickel chloride hexahydrate,and Fe^(3+)extracted from iron scale as raw materials.The zinc was selectively extracted from EAFD using CaO roasting followed by NH_(4)Cl solution leaching.The ferric ion was leached from iron scale using HCl solution as acid lixiviant.The experimental results demonstrate a high level of efficiency in the extraction of zinc,with a rate of 97.5%,and the leaching rate of ferric ion is 96.89%.The composition of the leaching solution is primary zinc and iron with low calcium,which is beneficial to the preparation of spinel ferrite.The influence of Ni content(x)and calcination temperature on the synthesis and magnetic properties of NixZn_(1-x)Fe_(2)O_(4)compounds was investigated by X-ray diffraction,scanning electron microscopy,and vibrating sample magnetometry.The results revealed that both Ni content and calcination temperature significantly affect the synthesis and magnetic properties of spinel NixZn_(1-x)Fe_(2)O_(4).Under the conditions of Ni content set at x=0.6,calcination temperature of 1100℃,and a duration of 2 h,a spinel NixZn_(1-x)Fe_(2)O_(4)with high saturation magnetization(Ms=65.7 A m2 kg-1)and low coercivity(Hc=0.056 A m^(-1))was obtained.
