Dust particles emitted from smelters can be hazardous to ecosystems and humans,as they are often enriched in metallic ***,we combined multi-method mineralogical analysis with a sophisticated size sorting approach for ...
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Dust particles emitted from smelters can be hazardous to ecosystems and humans,as they are often enriched in metallic ***,we combined multi-method mineralogical analysis with a sophisticated size sorting approach for copper smelting dust to study the nanosize-effect on heavy metal distribution,which has hitherto been *** types of dust were collected from a copper flash smelter and then size-sorted using a Dekati low-pressure *** showed that all three samples could easily sort out nanoscale dust particles(<1μm,grades 10–2)and even those smaller than 100 nm(grades 5–2).Especially for electrostatic precipitators dust,the mass fraction of nanoscale dust(<1μm)could reach 10.71%.The presence of heavy metals(Pb,Zn,Cu,and As)and their mineral species in dust was examined at various particle *** was discovered that different heavy metals are enriched on nanoparticles in specific *** micron-sized particles,heavy metals are generally found in discrete phases(e.g.,CuSO_(4),PbSO_(4),and As_(2)O_(3)).In nanoscale particles,the dominant phase is Fe_(3)O_(4),while heavy metals are mostly found in lattice substitution(e.g.,CuFe_(2)O_(4)and ZnFe_(2)O_(4)).Two distinct nano-dust morphologies were found:One with irregular mesh or chain structures consisting of particles of a few nanometers,and the other with polygonal crystals in larger sizes of hundreds of *** enrichment of heavy metals in the latter morphology is more pronounced,possibly because lattice substitution of heavy metals is more likely to occur when polycrystalline particles are formed.
Allelochemicals sustained-release microspheres(ACs-SMs)exhibited great inhibition effect on algae,however,few studies have focused on ACs-SMs toxicity on *** this study,the effects of single high-concentration ACs(15 ...
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Allelochemicals sustained-release microspheres(ACs-SMs)exhibited great inhibition effect on algae,however,few studies have focused on ACs-SMs toxicity on *** this study,the effects of single high-concentration ACs(15 mg/L,SH-ACs),repeated lowconcentration ACs(3×5 mg/L,RL-ACs)and ACs-SMs containing 15 mg/L ACs exposure on the ingestion,incorporation,and digestion of Daphniamagna Straus(DS)were investigated by stable isotope 15N labeling ***,the diversity and abundance of microflora in DS guts were determined by 16S rRNA genes and cloning *** results showed that SH-ACs exposure caused 50%and 33.3%death rates for newborn and adult DS,while RL-ACs exposure caused 10%death rate for newborn DS and no obvious effect on the activity of adult *** ACs-SMs exposure did not diminish the motility of both newborn and adult DS,indicating the lower acute toxicity of ***,SH-ACs inhibited the ingestion(-6.45%),incorporation(-47.1%)and digestion(-53.8%)abilities of DS and reduced the microbial abundance(-27.7%)in DS *** with SH-ACs,RL-ACs showed relatively low impact on the ingestion(-3.23%),incorporation(-5.89%)and digestion(-23.9%)abilities of ***,ACs-SMs enhanced the ingestion(+9.68%),incorporation(+52.9%)and digestion(+51.3%)abilities of DS and increased the microbial abundance(+10.7%)in DS *** ACs and ACs-SMs reduced the diversity of microflora in DS *** conclusion,ACs-SMs can release ACs sustainably and prolong the sustained release time,which not only effectively reduce the toxicity of ACs,but also had positive effects on DS.
Sulfonamide antibiotics(SAs)widely used have potentially negative effects on human beings and *** and advanced oxidation methods have been exten-sively applied in SAs wastewater *** this study,compared with Al^(3+)@BC...
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Sulfonamide antibiotics(SAs)widely used have potentially negative effects on human beings and *** and advanced oxidation methods have been exten-sively applied in SAs wastewater *** this study,compared with Al^(3+)@BC500 and Fe^(3+)@BC500,La^(3+)@BC500 for activating persulfate(S2O82−)had the best effect removal per-formance of sulfadiazine(SDZ)and sulfamethoxazole(SMX).Morphology,acidity,oxygen-containing functional groups,and loading of La^(3+)@BC500 were analyzed by techniques,in-cluding EA,BET,XRD,XPS,*** results show that with the increase of La^(3+)loading,the surface characteristics of biochar gradually changed from CaCO_(3)to LaCO_(3)*** EPR technology,it is proved that LaCO_(3)OH on the surface of La^(3+)@BC500 can not only acti-vate S2O82−to generate SO_(4)^(−)•,but also to produce•*** the optimization experiment,the optimal dosage of La^(3+)is between 0.05 and 0.2(mol/L)/*** had a good removal effect at pH(5-9),but SMX had a good removal effect only at pH=*** potential also proves that the material is more stable under acidic *** removal process of SDZ is more in accord with pseudo-first-order kinetics(R^(2)=0.9869),while SMX is more in line with pseudo-second order kinetics(R^(2)=0.9926).
The paper considers the simplest model of an export enterprise operating under uncertainty. The set of possible values of uncertain factors is specified using a scenario tree. Optimization problems for finding guarant...
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The paper discusses the principles of building a home quadruped robot’s vision system for stepping over obstacles and walking up stairs. The vision system measures the distance to the support surface at the places wh...
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Aircrafts heavily rely on sensors for effective control. However, sensor faults are bound to occur over time. It is imperative to devise a dependable sensor fault detection technique for aircrafts. This study presents...
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In this paper we present the results of numerical experiments on borrowers' coalition model designed for asset purchase. Specific digital data describes housing market. We focused on the visualization of obtained ...
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Strong coupling and complex nonlinearities increase the difficult of the dynamic modeling of the cooperative dual marine lifting system (DMLS). Moreover, it is a great challenge for DMLS model analysis while consideri...
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N,N-Dimethylformamide(DMF),a nitrogen-containing volatile organic compound(NVOC)with high emissions from the spray industry,has attracted increasing *** this study,Cu-ZSM-5 catalysts with different CuO particle sizes ...
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N,N-Dimethylformamide(DMF),a nitrogen-containing volatile organic compound(NVOC)with high emissions from the spray industry,has attracted increasing *** this study,Cu-ZSM-5 catalysts with different CuO particle sizes of 3,6,9 and 12 nm were synthesized and tested for DMF selective catalytic *** crystal structure and physicochemical properties of the catalyst were studied by various characterization *** catalytic activity increases with increasing CuO particle size,and complete conversion can be achieved at 300-350℃.The Cu-12 nm catalyst has the highest catalytic activity and can achieve complete conversion at 300℃.The Cu-6 nm sample has the highest N_(2)selectivity at lower temperatures,reaching 95%at 300℃.The activity of the catalysts is determined by the surface CuO cluster species,the bulk CuO species and the chemisorbed surface oxygen *** high N_(2)selectivity of the catalyst is attributed to the ratio of isolated Cu2+and bulk CuO species,and weak acidity is beneficial to the formation of N_(2).The results in this work will provide a new design of NVOC catalytic oxidation catalysts.
The air separation unit (ASU) is important for producing high-purity oxygen, nitrogen, and argon, and dynamic load change operation helps meet the needs of downstream industries. The ASU has an extremely long delay, a...
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