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
This work investigates the tribological behavior of bilayer surfaces formed by vertically aligned carbon nanotube(VACNT)films grown on top of cementite(Fe_(3)C)layers.Four Fe_(3)C–VACNT surfaces with different morpho...This work investigates the tribological behavior of bilayer surfaces formed by vertically aligned carbon nanotube(VACNT)films grown on top of cementite(Fe_(3)C)layers.Four Fe_(3)C–VACNT surfaces with different morphological and structural aspects were developed using plasma carburizing associated with the metal dusting phenomenon.Their tribological performance was assessed by reciprocating dry sliding tests using a ball-on-flat configuration.The combined analysis of the wear tracks through optical and scanning electron microscopy,energy-dispersive Xray spectroscopy,and Raman spectroscopy indicates that the catalyst particles of the carbon nanotubes are an essential factor controlling the tribosystem.Lubrication and wear depend on the ratio between the nanotubes and their catalyst particle lengths(LN/LP).VACNT films with LN/LP>20 promoted friction coefficient(COF)of~0.08 and reduced the wear rate of the ferrous substrate up to 70%.Wear rates showed an exponential reduction by increasing LN/LP.However,the VACNT film with LN/LP<10 induced severe abrasive wear since the beginning of the tribotests,leading to worse tribological performance than a reference surface composed of a single Fe_(3)C layer.Furthermore,the initial crystallinity of the VACNT films did not affect the solid lubrication or wear resistance of the surfaces.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
针对传统粮堆体积测量方法中设备成本高、依赖相机标定、复杂形态适配性差等问题,提出一种基于密集无约束体三维重建(dense and unconstrained stereo 3D reconstruction,DUSt3R)点云的散装粮堆体积智能估算方法。该方法利用DUSt3R的注...针对传统粮堆体积测量方法中设备成本高、依赖相机标定、复杂形态适配性差等问题,提出一种基于密集无约束体三维重建(dense and unconstrained stereo 3D reconstruction,DUSt3R)点云的散装粮堆体积智能估算方法。该方法利用DUSt3R的注意力机制与稠密匹配技术,实现端到端生成三维点云。构建基于粮堆特性的点云优化模块,结合统计滤波与RANSAC平面检测技术,提升点云噪声去除能力,并通过DBSCAN聚类实现粮堆与地面的精准分割。结果表明:该方法有效克服了对相机标定的依赖,显著提升了点云噪声处理与分割精度;通过动态网格投影与Alpha Shape曲面重建技术自适应拟合复杂粮堆形态,在保证测量准确性的同时大幅降低硬件成本,具备良好的工程适用性;在6种典型粮堆形态上开展试验验证,平均测量误差约为5%,仅需普通摄像头即可完成数据采集。该体积测量方法可与平粮机器人作业设备高效集成,为散装粮堆体积测量与自动化作业引导提供了低成本、高精度的技术解决方案。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
The dust cycle is a crucial component of the present-day Martian climate system.This study examines its multitimescale variability using an optimized 50-year simulation with the fully interactive scheme from the Globa...The dust cycle is a crucial component of the present-day Martian climate system.This study examines its multitimescale variability using an optimized 50-year simulation with the fully interactive scheme from the Global Open Planetary Atmospheric Model for Mars(GoMars),a newly developed Mars General Circulation Model(MGCM).GoMars is able to reproduce the diurnal,seasonal,and interannual characteristics of the dust cycle in several key aspects,with high repeatability in diurnal and seasonal variations during non-global dust storm(non-GDS)years.The model’s“climatology”(non-GDS years ensemble mean)captures the seasonal pattern and magnitude of the vertical–meridional dust distribution,validated against Mars Climate Database and Mars Climate Sounder observations.In the absence of direct observations,the GoMars-simulated near-surface wind stress lifting flux is evaluated through comparisons with other MGCMs(e.g.,MarsWRF),revealing consistent seasonal and spatial patterns.As for the diurnal cycle,the peak dust devil lifting flux occurs at 1200–1300 local time,matching the Mars Pathfinder measurements.The model also successfully captures the intense dust devil activity in Amazonis,a region identified as a major dust devil hotspot based on observational data.In GDS years,GoMars effectively reproduces spontaneous GDSs,capturing their observed onset times,locations,and dust transport patterns as exhibited in specific Martian years.The model also simulates significant interannual variability,with irregular GDS intervals along with reasonable dust–atmosphere interactions.展开更多
Central Asia is characterized by an arid climate and widespread desert distribution,with its sustainable development severely constrained by dust events.An objective understanding of the spatiotemporal patterns and dr...Central Asia is characterized by an arid climate and widespread desert distribution,with its sustainable development severely constrained by dust events.An objective understanding of the spatiotemporal patterns and driving forces of dust weather is highly important in this area.Based on the meteorological observations from 2000 to 2020,we examined the spatiotemporal characteristics of dust weather in the five Central Asian countries(Kazakhstan,Uzbekistan,Kyrgyzstan,Turkmenistan,and Tajikistan)via Theil-Sen trend analysis and Geodetector modeling method,quantitatively revealing the influence of environmental factors,such as temperature,precipitation,and vegetation,on the frequency of dust weather.The results showed that:(1)dust weather in Central Asia was mainly distributed in a large''dust belt''extending from west to east from northern part of the Caspian lowland desert,and concentrated in basins,plains,and other low-altitude areas.Strong dust weather mainly occurred in northern areas of the Aral Sea and southern edge of Central Asia,with a maximum annual frequency of 21.9%;(2)strong dust weather in Central Asia has fluctuated and slightly decreased since 2001.The highest frequency(1.1%)occurred in spring(from March to June);(3)from 2000 to 2020,changes such as spot shifting and shrinking occurred in the four main source areas(north of the Aral Sea,Kyzylkum Desert,Karakum Desert,and Garabogazköl Bay region),where sandstorms occurred in Central Asia,and northern Caspian lowland desert became the most important low-emission dust source in Central Asia;and(4)the combined effect of soil moisture and air temperature has the most significant influence on dust weather in Central Asia.This study provides a theoretical basis for sand prevention and sand control in Central Asia.In the future,Central Asia should focus on the rational utilization of land and water resources,and implement human interventions such as vegetation restoration and optimization of irrigation methods to curb further desertification in this area.展开更多
Sand and dust storms(SDSs)are natural disasters that frequently occur during spring in arid and semi-arid areas,causing serious impacts on human health,air quality,transportation,and agricultural production.Accurately...Sand and dust storms(SDSs)are natural disasters that frequently occur during spring in arid and semi-arid areas,causing serious impacts on human health,air quality,transportation,and agricultural production.Accurately simulating the occurrence and evolution of SDSs is of great significance for identifying dust sources and formulating effective disaster prevention measures.In this study,numerical simulations were conducted to reveal the dynamic spatiotemporal evolution and transport of dust load across East Asia.Using the Weather Research and Forecasting Model coupled with Chemistry(WRF-Chem)and European Centre for Medium-Range Weather Forecasts Reanalysis v5(ERA5)data,the most severe SDS events in the spring of 2023 in East Asia were numerically simulated.The simulated results were compared and validated using meteorological observations and multisource remote sensing data.The results showed that the simulated dust load in the peak regions showed close agreement with ground-based observations during the events.The primary dust sources in spring 2023 were identified as the western desert of Mongolia,the Gobi Desert,and the Taklimakan Desert in Xinjiang Uygur Autonomous Region of China.Peak dust load and maximum wind speed occurred almost simultaneously,indicating that high wind speed was the primary driver of sand and dust mobilization during individual SDS events.Increased surface vegetation covers partially mitigated wind-driven dust emissions.In April,strong winds over the Gobi Desert on the Mongolian Plateau predominantly drove cross-border SDSs along northwestern and northward transport pathways.Dust originating from Mongolia exerts a substantial influence on particulate dust load in the central and eastern parts of Inner Mongolia Autonomous Region of China.In contrast,their impact on the northwestern regions of China remains relatively limited.These findings contribute to understanding the source areas of SDS events in East Asia by simulating the dynamic evolution of SDSs and elucidating the relationships between SDS events and local geographical and environmental factors.展开更多
Sand dust belts span approximately one-fifth of the global land surface.In these regions,dust tends to settle on vegetation surfaces,altering the observed reflectance and affecting remote sensing detections.To enhance...Sand dust belts span approximately one-fifth of the global land surface.In these regions,dust tends to settle on vegetation surfaces,altering the observed reflectance and affecting remote sensing detections.To enhance the accuracy of maize growth monitoring in dust-affected regions,this study aims to quantify the effect of sand dust retention on maize during the tasseling stage in the Kashgar Prefecture,Xinjiang Uygur Autonomous Region,China,by analyzing changes in canopy reflectance and vegetation indices.First,field sampling was conducted to measure the key canopy structure parameters and dust retention levels of maize,and laboratory spectral measurements were performed on leaf spectral properties under gradient dust retention.The measured data were then used to drive the LargE-Scale remote sensing data and image Simulation framework(LESS)model for simulating realistic maize canopy spectra across different dust levels,with validation against Sentinel-2 imagery.Second,on the basis of the simulated and satellite-derived spectra,the dust resistance of 36 common vegetation indices was systematically evaluated,and new robust dust-resistant indices were developed.The results showed that compared with dust-free maize,the canopy reflectance of dust-retained maize followed an increase–decrease–increase pattern,with critical turning points at 735 and 1325 nm.The maximum reflectance difference of–0.11755(change rate:29.002%)occurred within the 735–1325 nm range at 24 g/m^(2)dust retention,and the minimum reflectance difference of 0.04285(change rate:148.950%)was observed in the 350–735 nm range under the same dust retention level.Among the 36 vegetation indices,only the global environment monitoring index(GEMI)and the ratio of transformed chlorophyll absorption in reflectance index to optimized soil-adjusted vegetation index(TCARI/OSAVI)exhibited dust resistance,with GEMI being effective below 6 g/m^(2)and TCARI/OSAVI remaining stable across all levels(average ratio:0.970).The newly developed indices in this study,(RE3–RE2)/(NIR–RE2),(RE3–RE2)/(RE4–RE2),and(NIR–RE2)/(RE4–RE2),retained values within the predefined dust-resistant range over the full dust retention levels of 0–24 g/m^(2),thus showing a more stable dust resistance compared with the commonly used 36 vegetation indices.Specially,(RE3–RE2)/(RE4–RE2)performed the most robustly in Sentinel-2 imagery,that is,58.020%of pixels were within the dust-resistant range,and an average ratio of 0.937 was obtained for the original-spectra index.This study provides a scientific basis for crop monitoring and management in dust-affected regions.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
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
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
Synthetic phenolic antioxidants(SPAs)are widely used in diverse industries due to their exceptional antioxidant characteristics.However,human exposure to SPAs may cause health problems.In this study,226 dust samples w...Synthetic phenolic antioxidants(SPAs)are widely used in diverse industries due to their exceptional antioxidant characteristics.However,human exposure to SPAs may cause health problems.In this study,226 dust samples were collected from 10 provinces in China,and six SPAs(three parent SPAs and their three transformation products)were analyzed.The concentrations of6SPAs(the sum of six target compounds)ranged from 15.4 to 3210 ng/g(geometric mean(GM):169 ng/g).The highest concentration of6SPAswas found in Sichuan Province(GM:349 ng/g),which was approximately 4 times higher than that in Hubei Province(81.6 ng/g)(p<0.05).The concentrations of butylated hydroxytoluene(BHT),2,2'-methylene bis(4-methyl-6–tert-butylphenol)(AO2246),2,6-di–tert–butyl–1,4-benzoquinone(BHT-Q),2,6-di–tert–butyl–4-(hydroxymethyl)phenol(BHT-OH),and ∑_(p)-SPAs were substantially higher in dust from urban areas than rural areas(p<0.05).AO2246 concentration in dust from homes(GM:0.400 ng/g)was about 4 times higher than that in workplaces(0.116 ng/g)(p<0.01).Significantly higherp-SPAs concentrations were found in dust from homes(GM:17.5 ng/g)than workplaces(11.4 ng/g)(p<0.01).The estimated daily intakes(EDIs)of ∑_(6)SPAs exposed through dust ingestion were 0.582,0.342,0.197,0.076,and 0.080 ng/kg bw/day in different age groups,and exposed through dermal contact was 0.358,0.252,0.174,0.167,and 0.177 ng/kg bw/day.EDIs showed that the exposure risks of SPAs decreased with age.This is the first work to determine SPAs in dust from10 provinces in China and investigate the spatial distribution of SPAs in those regions.展开更多
This study focuses on addressing ventilation and dust removal challenges during the construction of small-section tunnels using drilling and blasting techniques.Specifically,the research examines the shale gas gatheri...This study focuses on addressing ventilation and dust removal challenges during the construction of small-section tunnels using drilling and blasting techniques.Specifically,the research examines the shale gas gathering and transmission trunk line project in the Weiyuan and Luzhou blocks.To gain deeper insights into dust migration patterns,numerical simulations were conducted.The study further analyzed dust migration behavior in small-section tunnels and large steep-sloped shafts,taking into account various factors such as ventilation distance,tunnel slope,and section size.The results indicate that optimal ventilation occurs at distances of 15 and 13 m.Additionally,dust concentration was notably lower when the tunnel slope was 0°,suggesting that a flat slope is more advantageous for construction projects where the outlet wind speed remains constant.Moreover,as the tunnel’s cross-sectional size increases,dust concentration decreases significantly,further underscoring the benefits of larger tunnel sections in mitigating dust accumulation.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
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
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.
基金from the Luxembourg National Research Fund(FNR)under the HI3M project(BRIDGES2020/MS/15381200).
文摘This work investigates the tribological behavior of bilayer surfaces formed by vertically aligned carbon nanotube(VACNT)films grown on top of cementite(Fe_(3)C)layers.Four Fe_(3)C–VACNT surfaces with different morphological and structural aspects were developed using plasma carburizing associated with the metal dusting phenomenon.Their tribological performance was assessed by reciprocating dry sliding tests using a ball-on-flat configuration.The combined analysis of the wear tracks through optical and scanning electron microscopy,energy-dispersive Xray spectroscopy,and Raman spectroscopy indicates that the catalyst particles of the carbon nanotubes are an essential factor controlling the tribosystem.Lubrication and wear depend on the ratio between the nanotubes and their catalyst particle lengths(LN/LP).VACNT films with LN/LP>20 promoted friction coefficient(COF)of~0.08 and reduced the wear rate of the ferrous substrate up to 70%.Wear rates showed an exponential reduction by increasing LN/LP.However,the VACNT film with LN/LP<10 induced severe abrasive wear since the beginning of the tribotests,leading to worse tribological performance than a reference surface composed of a single Fe_(3)C layer.Furthermore,the initial crystallinity of the VACNT films did not affect the solid lubrication or wear resistance of the surfaces.
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.
文摘针对传统粮堆体积测量方法中设备成本高、依赖相机标定、复杂形态适配性差等问题,提出一种基于密集无约束体三维重建(dense and unconstrained stereo 3D reconstruction,DUSt3R)点云的散装粮堆体积智能估算方法。该方法利用DUSt3R的注意力机制与稠密匹配技术,实现端到端生成三维点云。构建基于粮堆特性的点云优化模块,结合统计滤波与RANSAC平面检测技术,提升点云噪声去除能力,并通过DBSCAN聚类实现粮堆与地面的精准分割。结果表明:该方法有效克服了对相机标定的依赖,显著提升了点云噪声处理与分割精度;通过动态网格投影与Alpha Shape曲面重建技术自适应拟合复杂粮堆形态,在保证测量准确性的同时大幅降低硬件成本,具备良好的工程适用性;在6种典型粮堆形态上开展试验验证,平均测量误差约为5%,仅需普通摄像头即可完成数据采集。该体积测量方法可与平粮机器人作业设备高效集成,为散装粮堆体积测量与自动化作业引导提供了低成本、高精度的技术解决方案。
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jointly supported by the National Natural Science Foundation of China(Grant No.42475135)the Key Technology Research Project of TW-3(TW3006)the IAP’s basic scientific research project during the 14th Five-Year Plan Period.
文摘The dust cycle is a crucial component of the present-day Martian climate system.This study examines its multitimescale variability using an optimized 50-year simulation with the fully interactive scheme from the Global Open Planetary Atmospheric Model for Mars(GoMars),a newly developed Mars General Circulation Model(MGCM).GoMars is able to reproduce the diurnal,seasonal,and interannual characteristics of the dust cycle in several key aspects,with high repeatability in diurnal and seasonal variations during non-global dust storm(non-GDS)years.The model’s“climatology”(non-GDS years ensemble mean)captures the seasonal pattern and magnitude of the vertical–meridional dust distribution,validated against Mars Climate Database and Mars Climate Sounder observations.In the absence of direct observations,the GoMars-simulated near-surface wind stress lifting flux is evaluated through comparisons with other MGCMs(e.g.,MarsWRF),revealing consistent seasonal and spatial patterns.As for the diurnal cycle,the peak dust devil lifting flux occurs at 1200–1300 local time,matching the Mars Pathfinder measurements.The model also successfully captures the intense dust devil activity in Amazonis,a region identified as a major dust devil hotspot based on observational data.In GDS years,GoMars effectively reproduces spontaneous GDSs,capturing their observed onset times,locations,and dust transport patterns as exhibited in specific Martian years.The model also simulates significant interannual variability,with irregular GDS intervals along with reasonable dust–atmosphere interactions.
基金funded by the National Natural Science Foundation of China(42571311).
文摘Central Asia is characterized by an arid climate and widespread desert distribution,with its sustainable development severely constrained by dust events.An objective understanding of the spatiotemporal patterns and driving forces of dust weather is highly important in this area.Based on the meteorological observations from 2000 to 2020,we examined the spatiotemporal characteristics of dust weather in the five Central Asian countries(Kazakhstan,Uzbekistan,Kyrgyzstan,Turkmenistan,and Tajikistan)via Theil-Sen trend analysis and Geodetector modeling method,quantitatively revealing the influence of environmental factors,such as temperature,precipitation,and vegetation,on the frequency of dust weather.The results showed that:(1)dust weather in Central Asia was mainly distributed in a large''dust belt''extending from west to east from northern part of the Caspian lowland desert,and concentrated in basins,plains,and other low-altitude areas.Strong dust weather mainly occurred in northern areas of the Aral Sea and southern edge of Central Asia,with a maximum annual frequency of 21.9%;(2)strong dust weather in Central Asia has fluctuated and slightly decreased since 2001.The highest frequency(1.1%)occurred in spring(from March to June);(3)from 2000 to 2020,changes such as spot shifting and shrinking occurred in the four main source areas(north of the Aral Sea,Kyzylkum Desert,Karakum Desert,and Garabogazköl Bay region),where sandstorms occurred in Central Asia,and northern Caspian lowland desert became the most important low-emission dust source in Central Asia;and(4)the combined effect of soil moisture and air temperature has the most significant influence on dust weather in Central Asia.This study provides a theoretical basis for sand prevention and sand control in Central Asia.In the future,Central Asia should focus on the rational utilization of land and water resources,and implement human interventions such as vegetation restoration and optimization of irrigation methods to curb further desertification in this area.
基金supported by the Science&Technology Fundamental Resources Investigation Program(2023FY100700)the Key Project of Innovation LREIS(KPI006)+1 种基金the Key R&D and Achievement Transformation Program of Inner Mongolia Autonomous Region(2023KJHZ0027)the Construction Project of China Knowledge Centre for Engineering Sciences and Technology(CKCEST-2023-1-5).
文摘Sand and dust storms(SDSs)are natural disasters that frequently occur during spring in arid and semi-arid areas,causing serious impacts on human health,air quality,transportation,and agricultural production.Accurately simulating the occurrence and evolution of SDSs is of great significance for identifying dust sources and formulating effective disaster prevention measures.In this study,numerical simulations were conducted to reveal the dynamic spatiotemporal evolution and transport of dust load across East Asia.Using the Weather Research and Forecasting Model coupled with Chemistry(WRF-Chem)and European Centre for Medium-Range Weather Forecasts Reanalysis v5(ERA5)data,the most severe SDS events in the spring of 2023 in East Asia were numerically simulated.The simulated results were compared and validated using meteorological observations and multisource remote sensing data.The results showed that the simulated dust load in the peak regions showed close agreement with ground-based observations during the events.The primary dust sources in spring 2023 were identified as the western desert of Mongolia,the Gobi Desert,and the Taklimakan Desert in Xinjiang Uygur Autonomous Region of China.Peak dust load and maximum wind speed occurred almost simultaneously,indicating that high wind speed was the primary driver of sand and dust mobilization during individual SDS events.Increased surface vegetation covers partially mitigated wind-driven dust emissions.In April,strong winds over the Gobi Desert on the Mongolian Plateau predominantly drove cross-border SDSs along northwestern and northward transport pathways.Dust originating from Mongolia exerts a substantial influence on particulate dust load in the central and eastern parts of Inner Mongolia Autonomous Region of China.In contrast,their impact on the northwestern regions of China remains relatively limited.These findings contribute to understanding the source areas of SDS events in East Asia by simulating the dynamic evolution of SDSs and elucidating the relationships between SDS events and local geographical and environmental factors.
基金supported by the Fundamental Research Funds for the Central Universities(N2001020)the National Natural Science Foundation of China(41201359).
文摘Sand dust belts span approximately one-fifth of the global land surface.In these regions,dust tends to settle on vegetation surfaces,altering the observed reflectance and affecting remote sensing detections.To enhance the accuracy of maize growth monitoring in dust-affected regions,this study aims to quantify the effect of sand dust retention on maize during the tasseling stage in the Kashgar Prefecture,Xinjiang Uygur Autonomous Region,China,by analyzing changes in canopy reflectance and vegetation indices.First,field sampling was conducted to measure the key canopy structure parameters and dust retention levels of maize,and laboratory spectral measurements were performed on leaf spectral properties under gradient dust retention.The measured data were then used to drive the LargE-Scale remote sensing data and image Simulation framework(LESS)model for simulating realistic maize canopy spectra across different dust levels,with validation against Sentinel-2 imagery.Second,on the basis of the simulated and satellite-derived spectra,the dust resistance of 36 common vegetation indices was systematically evaluated,and new robust dust-resistant indices were developed.The results showed that compared with dust-free maize,the canopy reflectance of dust-retained maize followed an increase–decrease–increase pattern,with critical turning points at 735 and 1325 nm.The maximum reflectance difference of–0.11755(change rate:29.002%)occurred within the 735–1325 nm range at 24 g/m^(2)dust retention,and the minimum reflectance difference of 0.04285(change rate:148.950%)was observed in the 350–735 nm range under the same dust retention level.Among the 36 vegetation indices,only the global environment monitoring index(GEMI)and the ratio of transformed chlorophyll absorption in reflectance index to optimized soil-adjusted vegetation index(TCARI/OSAVI)exhibited dust resistance,with GEMI being effective below 6 g/m^(2)and TCARI/OSAVI remaining stable across all levels(average ratio:0.970).The newly developed indices in this study,(RE3–RE2)/(NIR–RE2),(RE3–RE2)/(RE4–RE2),and(NIR–RE2)/(RE4–RE2),retained values within the predefined dust-resistant range over the full dust retention levels of 0–24 g/m^(2),thus showing a more stable dust resistance compared with the commonly used 36 vegetation indices.Specially,(RE3–RE2)/(RE4–RE2)performed the most robustly in Sentinel-2 imagery,that is,58.020%of pixels were within the dust-resistant range,and an average ratio of 0.937 was obtained for the original-spectra index.This study provides a scientific basis for crop monitoring and management in dust-affected regions.
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.
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supported by the National Key Research and Development Program of China(No.2023YFC3706602)the National Natural Science Foundation of China(Nos.22225605 and 22193051)the Strategic Priority Research Program of the Chinese Academy of Sciences(No.XDB0750200).
文摘Synthetic phenolic antioxidants(SPAs)are widely used in diverse industries due to their exceptional antioxidant characteristics.However,human exposure to SPAs may cause health problems.In this study,226 dust samples were collected from 10 provinces in China,and six SPAs(three parent SPAs and their three transformation products)were analyzed.The concentrations of6SPAs(the sum of six target compounds)ranged from 15.4 to 3210 ng/g(geometric mean(GM):169 ng/g).The highest concentration of6SPAswas found in Sichuan Province(GM:349 ng/g),which was approximately 4 times higher than that in Hubei Province(81.6 ng/g)(p<0.05).The concentrations of butylated hydroxytoluene(BHT),2,2'-methylene bis(4-methyl-6–tert-butylphenol)(AO2246),2,6-di–tert–butyl–1,4-benzoquinone(BHT-Q),2,6-di–tert–butyl–4-(hydroxymethyl)phenol(BHT-OH),and ∑_(p)-SPAs were substantially higher in dust from urban areas than rural areas(p<0.05).AO2246 concentration in dust from homes(GM:0.400 ng/g)was about 4 times higher than that in workplaces(0.116 ng/g)(p<0.01).Significantly higherp-SPAs concentrations were found in dust from homes(GM:17.5 ng/g)than workplaces(11.4 ng/g)(p<0.01).The estimated daily intakes(EDIs)of ∑_(6)SPAs exposed through dust ingestion were 0.582,0.342,0.197,0.076,and 0.080 ng/kg bw/day in different age groups,and exposed through dermal contact was 0.358,0.252,0.174,0.167,and 0.177 ng/kg bw/day.EDIs showed that the exposure risks of SPAs decreased with age.This is the first work to determine SPAs in dust from10 provinces in China and investigate the spatial distribution of SPAs in those regions.
基金supported by the National Natural Science Foundation of China under the Youth Project(Grant No.52204087)Additional support was provided by the Science and Technology Research Program of the Chongqing Municipal Education Commission(Grant No.KJQN202200746).
文摘This study focuses on addressing ventilation and dust removal challenges during the construction of small-section tunnels using drilling and blasting techniques.Specifically,the research examines the shale gas gathering and transmission trunk line project in the Weiyuan and Luzhou blocks.To gain deeper insights into dust migration patterns,numerical simulations were conducted.The study further analyzed dust migration behavior in small-section tunnels and large steep-sloped shafts,taking into account various factors such as ventilation distance,tunnel slope,and section size.The results indicate that optimal ventilation occurs at distances of 15 and 13 m.Additionally,dust concentration was notably lower when the tunnel slope was 0°,suggesting that a flat slope is more advantageous for construction projects where the outlet wind speed remains constant.Moreover,as the tunnel’s cross-sectional size increases,dust concentration decreases significantly,further underscoring the benefits of larger tunnel sections in mitigating dust accumulation.
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.
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.
