A novel porous binder was obtained from acid-treated kaolin. This new binder possessed abundant meso/macropores, good hydrothermal stability and heavy metal resistance. The prepared catalyst using new binder featured ...A novel porous binder was obtained from acid-treated kaolin. This new binder possessed abundant meso/macropores, good hydrothermal stability and heavy metal resistance. The prepared catalyst using new binder featured low attrition index and large pore volume. The catalysts were contaminated with Ni, V, and tested in a fixed-fluidized bed reactor unit. In comparison with the reference sample, the oil conversion achieved by the above-mentioned catalyst increased by 3.50 percentage points, and heavy oil yield decreased by 2.86 percentage points, while the total liquid yield and light oil yield increased by 2.82 percentage points and 0.79 percentage points, respectively. The perfect pore structure, good hydrothermal stability and heavy metal resistant performance of new binder were the possible causes leading to its outstanding performance.展开更多
Heavy metals(HMs)and antibiotic resistance have become serious environmental problems affecting soil and human health.Soil microorganisms play key roles in pollutant degradation and biogeochemical cycling processes;ho...Heavy metals(HMs)and antibiotic resistance have become serious environmental problems affecting soil and human health.Soil microorganisms play key roles in pollutant degradation and biogeochemical cycling processes;however,the interactions among HMs,soil microbial communities,and antibiotic resistance genes(ARGs)in agricultural soils remain unclear.Using quantitative real-time polymerase chain reaction and NovaSeq sequencing,we evaluated heavy metal contents,abundances of ARGs,soil bacterial community structure and functions,and their correlations in paddy soils at 43 sampling sites along the middle and lower reaches of the Yangtze River,central and eastern China.Our results showed the co-occurrence of HMs,ARGs,and HM resistance genes across all paddy soils.Additionally,significant positive associations were detected between HMs and resistance genes.Cadmium,czcA,and int1 were positively correlated with bacterial community diversity.The Mantel test showed that bacterial community composition and functions were significantly associated with HMs and resistance genes,such as Cd,Cr,Zn,copA,czcA,int1,and sul1.Moreover,HMs and ARGs were the major factors shaping soil bacterial communities;thus,HMs triggered proliferation of HM and antibiotic resistances by influencing the mobile genetic element(int1)and soil microbial communities.Our study revealed that HMs potentially drive the co-selection of ARGs by shifting soil bacterial community structure and functions,thereby increasing the potential risks to human health as well as ecological environment in the paddy soils along the middle and lower reaches of the Yangtze River.展开更多
In this study we evaluated the bacterial diversity in a soil sample from a site next to a chemical industrial factory previously contaminated with heavy metals. Analysis of 16S rDNA sequences amplified from DNA direct...In this study we evaluated the bacterial diversity in a soil sample from a site next to a chemical industrial factory previously contaminated with heavy metals. Analysis of 16S rDNA sequences amplified from DNA directly extracted from the soil revealed 17 different bacterial types （genera and/or species）. They included Polyangium spp., Sphingomonas spp., Variovorax spp., Hafina spp., Clostridia, Acidobacteria, the enterics and some uncultured strains. Microbes able to tolerate high concentrations of cadmium （500μmol/L and above） were also isolated from the soil. These isolates included strains of Acinetobacter （strain CD06）, Enterobacter sp. （strains CD01, CD03, CD04 and CD08） （similar strains also identified in culture-independent approach） and a strain of Stenotrophomonas sp. The results indicated that the species identified from direct analysis of 16S rDNA of the soil can be quite different from those strains obtained from enrichment cultures and the microbial activities for heavy metal resistance might be more appropriately addressed by the actual isolates.展开更多
The vip editors are pleased to present the upcoming Issue 5 of the Journal of Iron and Steel Research International as a special issue on“Anti-corrosive Coatings for Corrosion Protection”.This issue aims to collec...The vip editors are pleased to present the upcoming Issue 5 of the Journal of Iron and Steel Research International as a special issue on“Anti-corrosive Coatings for Corrosion Protection”.This issue aims to collect the cutting-edge developments in anti-corrosive coatings and corrosion-resistant metal materials.展开更多
Investigations were carried out to examine the effects of Co addition on the glass-forming ability （GFA） and corrosion resistance of Zr46Cu46AI8 bulk metallic glass in chloride-containing solution. It is found that ...Investigations were carried out to examine the effects of Co addition on the glass-forming ability （GFA） and corrosion resistance of Zr46Cu46AI8 bulk metallic glass in chloride-containing solution. It is found that the GFA of （Zr46Cu46Al8）100-xCox （x = 0, 1, 2, and 4 at.%） alloys reduces with the increase in Co content and correlates well with the parameters, such as the supercooled liquid region width ATx, the reduced glass transition temperature Trg and γ. The corrosion resistance is however found to be enhanced with the in- crease in Co concentration. The addition of Co causes the enrichment of Zr and Al, but depletes Cu in the surface films, which effectively enhances the corrosion potential and lowers the corrosion current density.展开更多
To better understand the diversity of metal resistance genetic determinant from microbes that survived at metal tailings in northwest of China, a highly elevated level of heavy metal containing region, genomic analyse...To better understand the diversity of metal resistance genetic determinant from microbes that survived at metal tailings in northwest of China, a highly elevated level of heavy metal containing region, genomic analyses was conducted using genome sequence of three native metal-resistant plant growth promoting bacteria（PGPB）. It shows that： Mesorhizobium amorphae CCNWGS0123 contains metal transporters from P-type ATPase, CDF（Cation Diffusion Facilitator）, Hup E/Ure J and CHR（chromate ion transporter） family involved in copper, zinc, nickel as well as chromate resistance and homeostasis. Meanwhile, the putative Cop A/Cue O system is expected to mediate copper resistance in Sinorhizobium meliloti CCNWSX0020 while Znt A transporter, assisted with putative Czc D, determines zinc tolerance in Agrobacterium tumefaciens CCNWGS0286. The greenhouse experiment provides the consistent evidence of the plant growth promoting effects of these microbes on their hosts by nitrogen fixation and/or indoleacetic acid（IAA） secretion,indicating a potential in-site phytoremediation usage in the mining tailing regions of China.展开更多
A total of 140 bacterial isolates have been successfully isolated from various organs of diseased American bullfrog （Rana catesbeiana） cultured in Malaysia. The most frequently isolated bacteria was Edwardsiella sp...A total of 140 bacterial isolates have been successfully isolated from various organs of diseased American bullfrog （Rana catesbeiana） cultured in Malaysia. The most frequently isolated bacteria was Edwardsiella spp. （46 isolates） followed by Aeromonas spp. （33 isolates）, Flavobacterium spp. （31 isolates）, and Vibrio spp. （30 isolates）. Majority of the bacterial isolates were found sensitive to furazolidone （85.0%）, chloramphenicol （85.0%）, oxolinic acid （90.0%）, florfenicol （95.0%）, and flumequine （97.5%）. On the other hand, most of the bacterial isolates were resistant to oleandomycin （77.5%） and lincomycin （87.5%）. Nitrofurantoin and flumequine can be inhibited the growth of all of Vibrio spp. whereas all isolates of Edwardsiella spp. were found sensitive to florfenicol and flumequine. Multiple antibiotic resistance （MAR） index were in range of 0.30-0.40, indicating that bacterial isolates from cultured bullfrogs may have received high risk exposure to the tested antibiotics. In addition, 90-100% of the isolates were resistant to copper, cadmium, and chromium. These results provided insight information on tolerance level of bacterial isolates from cultured bullfrogs to 21 antibiotics as well as heavy metals.展开更多
Multidrug-resistant(MDR)Escherichia coli,mainly extraintestinal pathogenic E.coli(ExPEC),has been widely reported in infections worldwide.In agricultural soils,manure is a hotspot for the dissemination of antimicrobia...Multidrug-resistant(MDR)Escherichia coli,mainly extraintestinal pathogenic E.coli(ExPEC),has been widely reported in infections worldwide.In agricultural soils,manure is a hotspot for the dissemination of antimicrobial resistance genes(ARGs)and pathogenic bacteria;however,MDR bacteria have also been reported in soils with no history of manure use.In addition,cross-resistance and co-resistance have been described as responsible for the metal-driven selection of bacteria resistant to antimicrobials.Therefore,the aim of this study was to analyze three MDR E.coli isolates obtained from Brazilian grain culture soil samples with no history of manure use by whole-genome sequencing.The MDR E.coli isolates were recovered from soils from corn and coffee fields,and presented resistance toβ-lactams,quinolones,aminoglycosides,tetracyclines,sulphonamides,and dihydrofolate reductase inhibitor.Resistome analysis showed ARGs to several antimicrobials(i.e.,β-lactams,tetracyclines,aminoglycosides,sulphonamides,trimethoprim,phenicols,fosfomycin,and macrolides)as well as several metal resistance genes and antibacterial biocide resistance genes.In addition,known mutations in quinolone-resistance-determining regions of GyrA(Ser83Leu and Asp87Asn),ParE(Ser458Thr),and ParC(Ser80Ile)were also detected.Virulome analysis showed the presence of virulence genes(lpfA,mcmA,gad,mchF,iroN,cma,and iss)associated with ExPEC.Multidrug-resistant ExPEC isolates were assigned to phylogenetic group B1.The presence of MDR B1-ExPEC in soil samples shows the ability of these isolates to survive in soils.This study reports for the first time some sequence types(i.e.,ST345,ST448,and ST1146)of MDR E.coli in Brazilian soils.Therefore,these findings contribute to the monitoring of antimicrobial resistance and surveillance studies based on whole-genome sequencing worldwide.展开更多
Four Zr–Cu–Fe–Al-based bulk metallic glasses（BMGs） with Zr contents greater than 65at% and minor additions of Nb were designed and prepared. The glass forming abilities, thermal stabilities, mechanical properties...Four Zr–Cu–Fe–Al-based bulk metallic glasses（BMGs） with Zr contents greater than 65at% and minor additions of Nb were designed and prepared. The glass forming abilities, thermal stabilities, mechanical properties, and corrosion resistance properties of the prepared BMGs were investigated. These BMGs exhibit moderate glass forming abilities along with superior fracture and yield strengths compared to previously reported Zr–Cu–Fe–Al BMGs. Specifically, the addition of Nb into this quaternary system remarkably increases the plastic strain to 27.5%, which is related to the high Poisson＇s ratio and low Young＇s and shear moduli. The Nb-bearing BMGs also exhibit a lower corrosion current density by about one order of magnitude and a wider passive region than 316 L steel in phosphate buffer solution（PBS, pH 7.4）. The combination of the optimized composition with high deformation ability, low Young＇s modulus, and excellent corrosion resistance properties indicates that this kind of BMG is promising for biomedical applications.展开更多
Calcium hexaluminate is one from such perspective materials. It is characterized by high refractoriness （ above 1 830 ~C ） , as well as properties stability in reducing atmosphere, high alkali- and slag-resistance...Calcium hexaluminate is one from such perspective materials. It is characterized by high refractoriness （ above 1 830 ~C ） , as well as properties stability in reducing atmosphere, high alkali- and slag-resistance, low thermal conductivity and wettability by molten metals. In this work influence researches of fused calcium hexaluminate material additive in amount of 5%, 15% amt 25% on the main properties of alumina refractories were carried out. It is established that, the refractories containing the additive of 25% calcium hexaluminate material are characterized by the highest properties, slightly impregnated with metal melt and the highest metal corrosion resistance. The alumina purging plugs fi）r blowing of metal with calcium hexaluminate material additive are produced and intended to one metallurgical plant of Ukraine for carrying out tests.展开更多
To better understand the assembly of the sturgeon egg microbiome, we purified six bacterial isolates from eggs and characterized their ability to form biofilms under the stress of tobramycin, with and without exogenou...To better understand the assembly of the sturgeon egg microbiome, we purified six bacterial isolates from eggs and characterized their ability to form biofilms under the stress of tobramycin, with and without exogenous protein. In experiments with single species biofilms, tobramycin reduced the metabolic activity of all isolates and increased biofilm biomass of three. The addition of exogenous protein to the assay countered the inhibition of biofilm and metabolic activity by tobramycin of <i>Pseudomonas</i> sp., <i>Brevundimonas</i> sp., <i>Flavobacterium columnare</i> and mixed biofilms of <i>Pseudomonas-F. columnare</i> and <i>Brevundimonas-Hydrogenophaga</i>. Two of the isolates (<i>Pseudomonas</i> spp.) that produced antimicrobial activity, were effective at reducing biofilm formation by <i>Brevundimonas</i>, but enhanced biofilm formation in other isolates. Increasing concentrations of Mg<sup>2+</sup> had no effect on biofilm formation but Ca<sup>2+</sup> enhanced biofilm formation of <i>Pseudomonas aeruginosa</i> PA01 (positive control) and <i>Brevundimonas</i>. Biofilm assembly by these two bacteria was inhibited by low concentrations of Ni<sup>2+</sup>. Mixed biofilms of <i>Brevundimonas</i> and <i>Hydrogenophage</i> consistently produced more robust biofilm than the strains in isolation, suggesting synergism. Established <i>Brevundimonas</i> biofilm appeared adept at recruiting pelagic <i>Acidovorax</i> and <i>Hydrogenophaga</i> into biofilm, suggesting that it plays an important role in the selection of species into the microbiome.展开更多
Due to its significant attributes,the liquid metal current limiter(LMCL)is considered a new strategy for limiting short-circuit current in the power grid.A resistive wall liquid metal current limiter(RWLMCL)is designe...Due to its significant attributes,the liquid metal current limiter(LMCL)is considered a new strategy for limiting short-circuit current in the power grid.A resistive wall liquid metal current limiter(RWLMCL)is designed to advance the starting current-limiting time.Experiments are performed to investigate the dynamic behaviors of liquid metal,and the influence of different currents on the liquid metal self-shrinkage effect is compared and analyzed.Furthermore,the liquid metal self-shrinkage effect is mathematically modeled,and the reason for the formation of arc plasma is obtained by simulation.The laws of arc plasma formation and the current transfer in the cavity are revealed,and the motion mechanisms are explained by physical principles.The simulations are in accordance with the test data.It is demonstrated that the sudden change of the current density at both ends of the wall causes the liquid metal to shrink and depress under the electromagnetic force,and the current starts to transfer from the liquid metal path to the wall resistance path.The RWLMCL can effectively advance the starting current-limiting time.展开更多
A heavy metal contaminated soil sample collected from a mine in Chonnam Province of South Korea was found to be a source of heavy metal adsorbing biosorbents. Chemical analyses showed high contents of lead （Pb） at 3...A heavy metal contaminated soil sample collected from a mine in Chonnam Province of South Korea was found to be a source of heavy metal adsorbing biosorbents. Chemical analyses showed high contents of lead （Pb） at 357 mg/kg and cyanide （CN） at 14.6 mg/kg in the soil. The experimental results showed that Penicillium sp. MRF-1 was the best lead resistant fungus among the four individual metal tolerant fungal species isolated from the soil. Molecular characterization of Penicillium sp. MRF-1 was determined using ITS regions sequences. Effects of pH, temperature and contact time on adsorption of Pb（Ⅱ） by Penicillium sp. MRF-1 were studied. Favorable conditions for maximum biosportion were found at pH 4 with 3 hr contact time. Biosorption of Pb（Ⅱ） gradually increased with increasing temperature. Efficient performance of the biosorbent was described using Langmuir and Freundlich isotherms. Adsorption kinetics was studied using pseudo first-order and pseudo second-order models. Biosorbent Penicillium sp. MRF-1 showed the maximum desorption in alkali conditions. Consistent adsorption/desorption potential of the biosorbent in repetitive cycles validated the efficacy of it in large scale. SEM studies given notes on surface modification of fungal biomass under metal stress and FT-IR results showed the presence of amino groups in the surface structure of the biosorbent. In conclusion, the new biosorbent Penicillium sp. MRF- 1 may potentially be used as an inexpensive, easily cultivatable material for the removal of lead from aqueous solution.展开更多
Physicochemical properties and metal contents of five dye-based textile effluents collected in summer and winter season, 201<span style="font-family:Verdana;"><span style="font-family:Verdana;&...Physicochemical properties and metal contents of five dye-based textile effluents collected in summer and winter season, 201<span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">6</span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"> from Savar, Dhaka, Bangladesh were within the recommended acceptable limit. The average value of all physicochemical parameters was found high in summer season except turbidity. A total of 94 heavy metal resistant bacteria (46 gram positive & 48 gram negative) were isolated from textile effluent sample</span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">s</span></span></span><span><span><span style="font-family:;" "=""><span style="font-family:Verdana;"> and among them 17 isolates were multi metal resistant. Highest tolerance level of the isolates was shown at 10 mM concentration against Pb. All the heavy metal resistant bacterial isolates were presumably grouped into 14 genera according to mor</span><span style="font-family:Verdana;">phological and biochemical assay. Three isolates designated WFB3c</span><span style="font-family:Verdana;"> (65.41%),</span><span style="font-family:Verdana;"> WFB4g (62%) and SFB5c (60.07%) were found to potentially degrade dye as </span><span style="font-family:Verdana;">well as tolerate heavy metal</span></span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">s</span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">. Three potential dye decolorizer isolates were</span></span></span><span><span><span style="font-family:;" "=""> <span><span style="font-family:Verdana;">screened out and most potential one (WFB3c) was identified as </span><i><span style="font-family:Verdana;">Proteus</span></i></span><span style="font-family:Verdana;"> <i>mirabilis</i> </span><span style="font-family:Verdana;">according to</span><span> </span><span style="font-family:Verdana;">the 16S rRNA identification.</span><span> </span><span style="font-family:Verdana;">The isolated bacterial strain </span><i><span style="font-family:Verdana;">Proteus</span></i><span style="font-family:Verdana;"> <i>mirabilis</i></span><span style="font-family:Verdana;"> would be a potential candidate for microbes based treatment to decolorize dye from textile effluents.</span></span></span></span>展开更多
The objective of the present work was to determine the influence of the neutral salt spray corrosion on the wear resistance of HVOF sprayed NiCr-Cr3C2 coating with intermediate layer. Ni-Zn-Al2O3 coatings as interlaye...The objective of the present work was to determine the influence of the neutral salt spray corrosion on the wear resistance of HVOF sprayed NiCr-Cr3C2 coating with intermediate layer. Ni-Zn-Al2O3 coatings as interlayers were prepared by low pressure cold spray（LPCS） between NiCr-Cr3C2 cermet coatings to form a sandwich structure to enhance the corrosion resistance properties. The tribological properties were examined using the UMT-3 fricition and wear tester by line-contact reciprocating sliding under dry and salt spray one week corrosion. The morphology, element distribution, and phase compositions of the coating and worn sufaces were analyzed by using scanning electron microscopy, energy dispersive spectrometry, and X-ray diffraction respectively. The corrosion behavior of the coating was studied by the open-circuit potential, the electrochemical impedance spectroscopy, potentiodynamic polarization, and salt spray corrosion methods. It is found that the sandwich structured coating has better corrosion resistance than the single layer coating. The results show that under dry wear conditions, the wear mechanism is abrasive and adhesive wear, whereas under salt spray corrosion conditions it becomes corrosion wear. The friction coefficient of the sandwich structured coating after salt spray corrosion is slightly lower than the dry friction coefficient, but the weight of the wear loss is lower than that under dry condition.展开更多
In real environment, it is unlikely that contaminants exist singly; environmental contamination with chemical mixtures is a norm. However, the impacts of chemical mixtures on environmental quality and ecosystem health...In real environment, it is unlikely that contaminants exist singly; environmental contamination with chemical mixtures is a norm. However, the impacts of chemical mixtures on environmental quality and ecosystem health have been overlooked in the past.Among the complex interactions between different contaminants, their relationship with the rise of antibiotic resistance（AR） is an emerging environmental concern. In this paper,we review recent progresses on how chemicals or chemical mixtures promote AR. We propose that, through co-selection, agents causing stress to bacteria may induce AR. The mechanisms for chemical mixtures to promote AR are also discussed. We also propose that,mechanistic understanding of co-selection of chemical mixtures for AR should be a future research priority in environmental health research.展开更多
Fe-based powder with a composition of Fe_（42.87）Cr_（15.98）Mo_（16.33）C_（15.94）B_（8.88）（at.%）was used to fabricate coatings by high-velocity oxygen fuel spraying.The effects of the spraying parameters on the...Fe-based powder with a composition of Fe_（42.87）Cr_（15.98）Mo_（16.33）C_（15.94）B_（8.88）（at.%）was used to fabricate coatings by high-velocity oxygen fuel spraying.The effects of the spraying parameters on the microstructure and the wear properties of the Fe-based alloy coatings were systematically studied.The results showed that the obtained Fe-based coatings with a thickness of about 400μm consisted of a large-volume amorphous phase and some nanocrystals.With increasing the fuel and oxygen flow rates,the porosity of the obtained coatings decreased.The coating deposited under optimized parameters exhibited the lowest porosity of 2.8%.The excellent wear resistance of this coating was attributed to the properties of the amorphous matrix and the presence of nanocrystals homogeneously distributed within the matrix.The wear mechanism of the coatings was discussed on the basis of observations of the worn surfaces.展开更多
Bipolar resistance switching characteristics are investigated in Cu/sputtered-HfO_2/Pt structure in the application of resistive random access memory（RRAM）.The conduction mechanism of the structure is characterized ...Bipolar resistance switching characteristics are investigated in Cu/sputtered-HfO_2/Pt structure in the application of resistive random access memory（RRAM）.The conduction mechanism of the structure is characterized to be SCLC conduction.The dependence of resistances in both high resistance state（HRS） and low resistance state（LRS） on the temperature and device area are studied.Then,the composition and chemical bonding state of Cu and Hf at Cu/HfO_2 interface region are analyzed by x-ray photoelectron spectroscopy（XPS）.Combining the electrical characteristics and the chemical structure at the interface,a model for the resistive switching effect in Cu/HfO_2/Pt stack is proposed.According to this model,the generation and recovery of oxygen vacancies in the HfO_2 film are responsible for the resistance change.展开更多
With the increasing use of antibiotics and rare earth elements(REE)during the coronavirus disease(COVID-19)pandemic,the co-occurrence of sulfamethoxazole(SMX)and gadolinium(Gd)has increased in wastewater treatment pla...With the increasing use of antibiotics and rare earth elements(REE)during the coronavirus disease(COVID-19)pandemic,the co-occurrence of sulfamethoxazole(SMX)and gadolinium(Gd)has increased in wastewater treatment plants(WWTPs).However,the effects of SMX and Gd exposure on the transmission of antibiotic resistance genes(ARGs)and heavy metal resistance genes(MRGs)remain unknown.This study investigated the impacts of SMX and Gd on the fate of ARGs and MRGs in an activated sludge system.The diversity and relative abundance of ARGs,MRGs,and mobile genetic elements(MGEs)were detected by metagenomic sequencing.The results revealed an increased abundance of ARGs but a decreased abundance of MRGs under the joint effect of SMX and Gd.In addition,Gd alone exerted adverse effects on the proliferation and spread of ARGs and MRGs.However,SMX alone resulted in an increase in the diversity of ARGs and MRGs and promoted the growth of Pseudomonas,Thauera,and Streptomyces in the activated sludge system.Interestingly,a positive correlation was observed between most ARGs and MGEs.These findings provide comprehensive insights into the effects of co-occurring REEs and antibiotics on the fate of ARGs,MRGs,and MGEs,providing evidence to assist in controlling the spread and proliferation of ARGs and MRGs in activated sludge systems.展开更多
Microplastics existing widely in different matrices have been regarded as a reservoir for emerging contaminants.Mariculture systems have been observed to host microplastics and antibiotic resistance genes(ARGs).Howeve...Microplastics existing widely in different matrices have been regarded as a reservoir for emerging contaminants.Mariculture systems have been observed to host microplastics and antibiotic resistance genes(ARGs).However,more information on proliferation of ARGs and metal resistance genes(MRGs)in mariculture system at the presence of microplastics is needed.This study used metagenomic analysis to investigate the distribution of ARGs and MRGs in water and microplastics of a typical mariculture pond.Total 18 types including 174 subtypes of ARGs were detected with the total relative abundances of 1.22/1.25 copies per 16S rRNA copy for microplastics/water.Chloramphenicol resistance genes were the dominant ARGs with the abundance of 0.35/0.42 copies per 16S rRNA copy for microplastics/water.Intergron intI1 was dominant gene among 6 detected mobile genetic elements(MGEs)with the abundance of 75.46/68.70 copies per 16S rRNA copy for water/microplastics.Total 9 types including 46 subtypes of MRGs were detected with total abundance of 5.02×10^(2)/6.39×10^(2)copies per 16S rRNA copy for water/microplastics while genes resistant to copper and iron served as the dominant MRGs.Proteobacteria,Bacteroidetes,and Actinobacteria accounted for 84.2%/89.5%of total microbial community in microplastics/water.ARGs with relatively high abundance were significantly positively related to major genera,MGEs,and MRGs.Microplastics in mariculture system could enrich most of MRGs and some ARGs to serve as potential reservoir for these pollutants.The findings of this study will provide important information on resistance gene pollution at presence of microplastics in the mariculture system for further proposing suitable strategy of environmental management.展开更多
基金the Department of Science and Technology Management of PetroChina for providing financial support
文摘A novel porous binder was obtained from acid-treated kaolin. This new binder possessed abundant meso/macropores, good hydrothermal stability and heavy metal resistance. The prepared catalyst using new binder featured low attrition index and large pore volume. The catalysts were contaminated with Ni, V, and tested in a fixed-fluidized bed reactor unit. In comparison with the reference sample, the oil conversion achieved by the above-mentioned catalyst increased by 3.50 percentage points, and heavy oil yield decreased by 2.86 percentage points, while the total liquid yield and light oil yield increased by 2.82 percentage points and 0.79 percentage points, respectively. The perfect pore structure, good hydrothermal stability and heavy metal resistant performance of new binder were the possible causes leading to its outstanding performance.
基金sponsored by the Outstanding Innovative Research Team for Molecular Enzymology and Detection in Anhui Provincial Universities,China(No.2022AH010012)the Program of Anhui Provincial Key Laboratory of the Conservation and Exploitation of Biological Resources,China(No.swzy202001)。
文摘Heavy metals(HMs)and antibiotic resistance have become serious environmental problems affecting soil and human health.Soil microorganisms play key roles in pollutant degradation and biogeochemical cycling processes;however,the interactions among HMs,soil microbial communities,and antibiotic resistance genes(ARGs)in agricultural soils remain unclear.Using quantitative real-time polymerase chain reaction and NovaSeq sequencing,we evaluated heavy metal contents,abundances of ARGs,soil bacterial community structure and functions,and their correlations in paddy soils at 43 sampling sites along the middle and lower reaches of the Yangtze River,central and eastern China.Our results showed the co-occurrence of HMs,ARGs,and HM resistance genes across all paddy soils.Additionally,significant positive associations were detected between HMs and resistance genes.Cadmium,czcA,and int1 were positively correlated with bacterial community diversity.The Mantel test showed that bacterial community composition and functions were significantly associated with HMs and resistance genes,such as Cd,Cr,Zn,copA,czcA,int1,and sul1.Moreover,HMs and ARGs were the major factors shaping soil bacterial communities;thus,HMs triggered proliferation of HM and antibiotic resistances by influencing the mobile genetic element(int1)and soil microbial communities.Our study revealed that HMs potentially drive the co-selection of ARGs by shifting soil bacterial community structure and functions,thereby increasing the potential risks to human health as well as ecological environment in the paddy soils along the middle and lower reaches of the Yangtze River.
文摘In this study we evaluated the bacterial diversity in a soil sample from a site next to a chemical industrial factory previously contaminated with heavy metals. Analysis of 16S rDNA sequences amplified from DNA directly extracted from the soil revealed 17 different bacterial types （genera and/or species）. They included Polyangium spp., Sphingomonas spp., Variovorax spp., Hafina spp., Clostridia, Acidobacteria, the enterics and some uncultured strains. Microbes able to tolerate high concentrations of cadmium （500μmol/L and above） were also isolated from the soil. These isolates included strains of Acinetobacter （strain CD06）, Enterobacter sp. （strains CD01, CD03, CD04 and CD08） （similar strains also identified in culture-independent approach） and a strain of Stenotrophomonas sp. The results indicated that the species identified from direct analysis of 16S rDNA of the soil can be quite different from those strains obtained from enrichment cultures and the microbial activities for heavy metal resistance might be more appropriately addressed by the actual isolates.
文摘The vip editors are pleased to present the upcoming Issue 5 of the Journal of Iron and Steel Research International as a special issue on“Anti-corrosive Coatings for Corrosion Protection”.This issue aims to collect the cutting-edge developments in anti-corrosive coatings and corrosion-resistant metal materials.
基金financially supported by the National Natural Science Foundation of China (No. 51401139)the Basic Research Program of Jiangsu Province (No. BK20130304)
文摘Investigations were carried out to examine the effects of Co addition on the glass-forming ability （GFA） and corrosion resistance of Zr46Cu46AI8 bulk metallic glass in chloride-containing solution. It is found that the GFA of （Zr46Cu46Al8）100-xCox （x = 0, 1, 2, and 4 at.%） alloys reduces with the increase in Co content and correlates well with the parameters, such as the supercooled liquid region width ATx, the reduced glass transition temperature Trg and γ. The corrosion resistance is however found to be enhanced with the in- crease in Co concentration. The addition of Co causes the enrichment of Zr and Al, but depletes Cu in the surface films, which effectively enhances the corrosion potential and lowers the corrosion current density.
基金supported by the National High Technology Research and Development Program (863) of China (No.2012AA101402)the National Science Foundation of China (Nos.31125007,31370142)
文摘To better understand the diversity of metal resistance genetic determinant from microbes that survived at metal tailings in northwest of China, a highly elevated level of heavy metal containing region, genomic analyses was conducted using genome sequence of three native metal-resistant plant growth promoting bacteria（PGPB）. It shows that： Mesorhizobium amorphae CCNWGS0123 contains metal transporters from P-type ATPase, CDF（Cation Diffusion Facilitator）, Hup E/Ure J and CHR（chromate ion transporter） family involved in copper, zinc, nickel as well as chromate resistance and homeostasis. Meanwhile, the putative Cop A/Cue O system is expected to mediate copper resistance in Sinorhizobium meliloti CCNWSX0020 while Znt A transporter, assisted with putative Czc D, determines zinc tolerance in Agrobacterium tumefaciens CCNWGS0286. The greenhouse experiment provides the consistent evidence of the plant growth promoting effects of these microbes on their hosts by nitrogen fixation and/or indoleacetic acid（IAA） secretion,indicating a potential in-site phytoremediation usage in the mining tailing regions of China.
基金funded by Universiti Malaysia Terengganu, Malaysia
文摘A total of 140 bacterial isolates have been successfully isolated from various organs of diseased American bullfrog （Rana catesbeiana） cultured in Malaysia. The most frequently isolated bacteria was Edwardsiella spp. （46 isolates） followed by Aeromonas spp. （33 isolates）, Flavobacterium spp. （31 isolates）, and Vibrio spp. （30 isolates）. Majority of the bacterial isolates were found sensitive to furazolidone （85.0%）, chloramphenicol （85.0%）, oxolinic acid （90.0%）, florfenicol （95.0%）, and flumequine （97.5%）. On the other hand, most of the bacterial isolates were resistant to oleandomycin （77.5%） and lincomycin （87.5%）. Nitrofurantoin and flumequine can be inhibited the growth of all of Vibrio spp. whereas all isolates of Edwardsiella spp. were found sensitive to florfenicol and flumequine. Multiple antibiotic resistance （MAR） index were in range of 0.30-0.40, indicating that bacterial isolates from cultured bullfrogs may have received high risk exposure to the tested antibiotics. In addition, 90-100% of the isolates were resistant to copper, cadmium, and chromium. These results provided insight information on tolerance level of bacterial isolates from cultured bullfrogs to 21 antibiotics as well as heavy metals.
基金supported by the Fundação de AmparoàPesquisa do Estado de São Paulo(FAPESP,Nos.2018/19539-0 and 2018/01890-3)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior(CAPES,Nos.88882.180855/2018-01 and Finance code 001),Brazil。
文摘Multidrug-resistant(MDR)Escherichia coli,mainly extraintestinal pathogenic E.coli(ExPEC),has been widely reported in infections worldwide.In agricultural soils,manure is a hotspot for the dissemination of antimicrobial resistance genes(ARGs)and pathogenic bacteria;however,MDR bacteria have also been reported in soils with no history of manure use.In addition,cross-resistance and co-resistance have been described as responsible for the metal-driven selection of bacteria resistant to antimicrobials.Therefore,the aim of this study was to analyze three MDR E.coli isolates obtained from Brazilian grain culture soil samples with no history of manure use by whole-genome sequencing.The MDR E.coli isolates were recovered from soils from corn and coffee fields,and presented resistance toβ-lactams,quinolones,aminoglycosides,tetracyclines,sulphonamides,and dihydrofolate reductase inhibitor.Resistome analysis showed ARGs to several antimicrobials(i.e.,β-lactams,tetracyclines,aminoglycosides,sulphonamides,trimethoprim,phenicols,fosfomycin,and macrolides)as well as several metal resistance genes and antibacterial biocide resistance genes.In addition,known mutations in quinolone-resistance-determining regions of GyrA(Ser83Leu and Asp87Asn),ParE(Ser458Thr),and ParC(Ser80Ile)were also detected.Virulome analysis showed the presence of virulence genes(lpfA,mcmA,gad,mchF,iroN,cma,and iss)associated with ExPEC.Multidrug-resistant ExPEC isolates were assigned to phylogenetic group B1.The presence of MDR B1-ExPEC in soil samples shows the ability of these isolates to survive in soils.This study reports for the first time some sequence types(i.e.,ST345,ST448,and ST1146)of MDR E.coli in Brazilian soils.Therefore,these findings contribute to the monitoring of antimicrobial resistance and surveillance studies based on whole-genome sequencing worldwide.
基金financially supported by the National Natural Science Foundation of China (No. 51271018)the Proprietary Program of the State Key Laboratory for Advanced Metals and Materials,University of Science and Technology Beijing (Nos.2011Z-01 and 2012Z-01)
文摘Four Zr–Cu–Fe–Al-based bulk metallic glasses（BMGs） with Zr contents greater than 65at% and minor additions of Nb were designed and prepared. The glass forming abilities, thermal stabilities, mechanical properties, and corrosion resistance properties of the prepared BMGs were investigated. These BMGs exhibit moderate glass forming abilities along with superior fracture and yield strengths compared to previously reported Zr–Cu–Fe–Al BMGs. Specifically, the addition of Nb into this quaternary system remarkably increases the plastic strain to 27.5%, which is related to the high Poisson＇s ratio and low Young＇s and shear moduli. The Nb-bearing BMGs also exhibit a lower corrosion current density by about one order of magnitude and a wider passive region than 316 L steel in phosphate buffer solution（PBS, pH 7.4）. The combination of the optimized composition with high deformation ability, low Young＇s modulus, and excellent corrosion resistance properties indicates that this kind of BMG is promising for biomedical applications.
文摘Calcium hexaluminate is one from such perspective materials. It is characterized by high refractoriness （ above 1 830 ~C ） , as well as properties stability in reducing atmosphere, high alkali- and slag-resistance, low thermal conductivity and wettability by molten metals. In this work influence researches of fused calcium hexaluminate material additive in amount of 5%, 15% amt 25% on the main properties of alumina refractories were carried out. It is established that, the refractories containing the additive of 25% calcium hexaluminate material are characterized by the highest properties, slightly impregnated with metal melt and the highest metal corrosion resistance. The alumina purging plugs fi）r blowing of metal with calcium hexaluminate material additive are produced and intended to one metallurgical plant of Ukraine for carrying out tests.
文摘To better understand the assembly of the sturgeon egg microbiome, we purified six bacterial isolates from eggs and characterized their ability to form biofilms under the stress of tobramycin, with and without exogenous protein. In experiments with single species biofilms, tobramycin reduced the metabolic activity of all isolates and increased biofilm biomass of three. The addition of exogenous protein to the assay countered the inhibition of biofilm and metabolic activity by tobramycin of <i>Pseudomonas</i> sp., <i>Brevundimonas</i> sp., <i>Flavobacterium columnare</i> and mixed biofilms of <i>Pseudomonas-F. columnare</i> and <i>Brevundimonas-Hydrogenophaga</i>. Two of the isolates (<i>Pseudomonas</i> spp.) that produced antimicrobial activity, were effective at reducing biofilm formation by <i>Brevundimonas</i>, but enhanced biofilm formation in other isolates. Increasing concentrations of Mg<sup>2+</sup> had no effect on biofilm formation but Ca<sup>2+</sup> enhanced biofilm formation of <i>Pseudomonas aeruginosa</i> PA01 (positive control) and <i>Brevundimonas</i>. Biofilm assembly by these two bacteria was inhibited by low concentrations of Ni<sup>2+</sup>. Mixed biofilms of <i>Brevundimonas</i> and <i>Hydrogenophage</i> consistently produced more robust biofilm than the strains in isolation, suggesting synergism. Established <i>Brevundimonas</i> biofilm appeared adept at recruiting pelagic <i>Acidovorax</i> and <i>Hydrogenophaga</i> into biofilm, suggesting that it plays an important role in the selection of species into the microbiome.
基金supported by National Natural Science Foundation of China(No.52177131)the Interdisciplinary Program of Wuhan National High Magnetic Field Center(No.WHMFC202130)Huazhong University of Science and Technology。
文摘Due to its significant attributes,the liquid metal current limiter(LMCL)is considered a new strategy for limiting short-circuit current in the power grid.A resistive wall liquid metal current limiter(RWLMCL)is designed to advance the starting current-limiting time.Experiments are performed to investigate the dynamic behaviors of liquid metal,and the influence of different currents on the liquid metal self-shrinkage effect is compared and analyzed.Furthermore,the liquid metal self-shrinkage effect is mathematically modeled,and the reason for the formation of arc plasma is obtained by simulation.The laws of arc plasma formation and the current transfer in the cavity are revealed,and the motion mechanisms are explained by physical principles.The simulations are in accordance with the test data.It is demonstrated that the sudden change of the current density at both ends of the wall causes the liquid metal to shrink and depress under the electromagnetic force,and the current starts to transfer from the liquid metal path to the wall resistance path.The RWLMCL can effectively advance the starting current-limiting time.
基金supported by Agricultural R&D Promotion Center,South Korea (No. 060101001)
文摘A heavy metal contaminated soil sample collected from a mine in Chonnam Province of South Korea was found to be a source of heavy metal adsorbing biosorbents. Chemical analyses showed high contents of lead （Pb） at 357 mg/kg and cyanide （CN） at 14.6 mg/kg in the soil. The experimental results showed that Penicillium sp. MRF-1 was the best lead resistant fungus among the four individual metal tolerant fungal species isolated from the soil. Molecular characterization of Penicillium sp. MRF-1 was determined using ITS regions sequences. Effects of pH, temperature and contact time on adsorption of Pb（Ⅱ） by Penicillium sp. MRF-1 were studied. Favorable conditions for maximum biosportion were found at pH 4 with 3 hr contact time. Biosorption of Pb（Ⅱ） gradually increased with increasing temperature. Efficient performance of the biosorbent was described using Langmuir and Freundlich isotherms. Adsorption kinetics was studied using pseudo first-order and pseudo second-order models. Biosorbent Penicillium sp. MRF-1 showed the maximum desorption in alkali conditions. Consistent adsorption/desorption potential of the biosorbent in repetitive cycles validated the efficacy of it in large scale. SEM studies given notes on surface modification of fungal biomass under metal stress and FT-IR results showed the presence of amino groups in the surface structure of the biosorbent. In conclusion, the new biosorbent Penicillium sp. MRF- 1 may potentially be used as an inexpensive, easily cultivatable material for the removal of lead from aqueous solution.
文摘Physicochemical properties and metal contents of five dye-based textile effluents collected in summer and winter season, 201<span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">6</span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"> from Savar, Dhaka, Bangladesh were within the recommended acceptable limit. The average value of all physicochemical parameters was found high in summer season except turbidity. A total of 94 heavy metal resistant bacteria (46 gram positive & 48 gram negative) were isolated from textile effluent sample</span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">s</span></span></span><span><span><span style="font-family:;" "=""><span style="font-family:Verdana;"> and among them 17 isolates were multi metal resistant. Highest tolerance level of the isolates was shown at 10 mM concentration against Pb. All the heavy metal resistant bacterial isolates were presumably grouped into 14 genera according to mor</span><span style="font-family:Verdana;">phological and biochemical assay. Three isolates designated WFB3c</span><span style="font-family:Verdana;"> (65.41%),</span><span style="font-family:Verdana;"> WFB4g (62%) and SFB5c (60.07%) were found to potentially degrade dye as </span><span style="font-family:Verdana;">well as tolerate heavy metal</span></span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">s</span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">. Three potential dye decolorizer isolates were</span></span></span><span><span><span style="font-family:;" "=""> <span><span style="font-family:Verdana;">screened out and most potential one (WFB3c) was identified as </span><i><span style="font-family:Verdana;">Proteus</span></i></span><span style="font-family:Verdana;"> <i>mirabilis</i> </span><span style="font-family:Verdana;">according to</span><span> </span><span style="font-family:Verdana;">the 16S rRNA identification.</span><span> </span><span style="font-family:Verdana;">The isolated bacterial strain </span><i><span style="font-family:Verdana;">Proteus</span></i><span style="font-family:Verdana;"> <i>mirabilis</i></span><span style="font-family:Verdana;"> would be a potential candidate for microbes based treatment to decolorize dye from textile effluents.</span></span></span></span>
基金Funded by the High-Tech Research and Development Program of China(No.2012AA09A203)the Fundmental Research Funds for the Central Universities(No.15CX06061A)the Postgraduate Innovation Project of China University of Petroleum(East China)(No.YCXJ2016059)
文摘The objective of the present work was to determine the influence of the neutral salt spray corrosion on the wear resistance of HVOF sprayed NiCr-Cr3C2 coating with intermediate layer. Ni-Zn-Al2O3 coatings as interlayers were prepared by low pressure cold spray（LPCS） between NiCr-Cr3C2 cermet coatings to form a sandwich structure to enhance the corrosion resistance properties. The tribological properties were examined using the UMT-3 fricition and wear tester by line-contact reciprocating sliding under dry and salt spray one week corrosion. The morphology, element distribution, and phase compositions of the coating and worn sufaces were analyzed by using scanning electron microscopy, energy dispersive spectrometry, and X-ray diffraction respectively. The corrosion behavior of the coating was studied by the open-circuit potential, the electrochemical impedance spectroscopy, potentiodynamic polarization, and salt spray corrosion methods. It is found that the sandwich structured coating has better corrosion resistance than the single layer coating. The results show that under dry wear conditions, the wear mechanism is abrasive and adhesive wear, whereas under salt spray corrosion conditions it becomes corrosion wear. The friction coefficient of the sandwich structured coating after salt spray corrosion is slightly lower than the dry friction coefficient, but the weight of the wear loss is lower than that under dry condition.
基金supported by the National Key Research and Development Plan(No.2016YFD0800205)the National Natural Science Foundation of China(Nos.41571130063 and31770127)the Strategic Priority Research Program of Chinese Academy of Sciences(No.XDB15020402)
文摘In real environment, it is unlikely that contaminants exist singly; environmental contamination with chemical mixtures is a norm. However, the impacts of chemical mixtures on environmental quality and ecosystem health have been overlooked in the past.Among the complex interactions between different contaminants, their relationship with the rise of antibiotic resistance（AR） is an emerging environmental concern. In this paper,we review recent progresses on how chemicals or chemical mixtures promote AR. We propose that, through co-selection, agents causing stress to bacteria may induce AR. The mechanisms for chemical mixtures to promote AR are also discussed. We also propose that,mechanistic understanding of co-selection of chemical mixtures for AR should be a future research priority in environmental health research.
基金Item Sponsored by National Natural Science Foundation of China(51205001)Key Project of Natural Science of Education Department of Anhui Province of China(KJ2014A023)Scientific Research Starting Foundation of Anhui Polytechnic University of China(2012YQQ006)
文摘Fe-based powder with a composition of Fe_（42.87）Cr_（15.98）Mo_（16.33）C_（15.94）B_（8.88）（at.%）was used to fabricate coatings by high-velocity oxygen fuel spraying.The effects of the spraying parameters on the microstructure and the wear properties of the Fe-based alloy coatings were systematically studied.The results showed that the obtained Fe-based coatings with a thickness of about 400μm consisted of a large-volume amorphous phase and some nanocrystals.With increasing the fuel and oxygen flow rates,the porosity of the obtained coatings decreased.The coating deposited under optimized parameters exhibited the lowest porosity of 2.8%.The excellent wear resistance of this coating was attributed to the properties of the amorphous matrix and the presence of nanocrystals homogeneously distributed within the matrix.The wear mechanism of the coatings was discussed on the basis of observations of the worn surfaces.
基金Project supported by the Research Fund of the State Key Laboratory of Solidification Processing(NWPU),China(Grant No.155-QP-2016)the Fundamental Research Funds for the Central Universities of China(Grant No.3102014JCQ01032)the 111 Project of China(Grant No.B08040)
文摘Bipolar resistance switching characteristics are investigated in Cu/sputtered-HfO_2/Pt structure in the application of resistive random access memory（RRAM）.The conduction mechanism of the structure is characterized to be SCLC conduction.The dependence of resistances in both high resistance state（HRS） and low resistance state（LRS） on the temperature and device area are studied.Then,the composition and chemical bonding state of Cu and Hf at Cu/HfO_2 interface region are analyzed by x-ray photoelectron spectroscopy（XPS）.Combining the electrical characteristics and the chemical structure at the interface,a model for the resistive switching effect in Cu/HfO_2/Pt stack is proposed.According to this model,the generation and recovery of oxygen vacancies in the HfO_2 film are responsible for the resistance change.
基金supported by the National Key R&D Program of China(No.2019YFC0408500).
文摘With the increasing use of antibiotics and rare earth elements(REE)during the coronavirus disease(COVID-19)pandemic,the co-occurrence of sulfamethoxazole(SMX)and gadolinium(Gd)has increased in wastewater treatment plants(WWTPs).However,the effects of SMX and Gd exposure on the transmission of antibiotic resistance genes(ARGs)and heavy metal resistance genes(MRGs)remain unknown.This study investigated the impacts of SMX and Gd on the fate of ARGs and MRGs in an activated sludge system.The diversity and relative abundance of ARGs,MRGs,and mobile genetic elements(MGEs)were detected by metagenomic sequencing.The results revealed an increased abundance of ARGs but a decreased abundance of MRGs under the joint effect of SMX and Gd.In addition,Gd alone exerted adverse effects on the proliferation and spread of ARGs and MRGs.However,SMX alone resulted in an increase in the diversity of ARGs and MRGs and promoted the growth of Pseudomonas,Thauera,and Streptomyces in the activated sludge system.Interestingly,a positive correlation was observed between most ARGs and MGEs.These findings provide comprehensive insights into the effects of co-occurring REEs and antibiotics on the fate of ARGs,MRGs,and MGEs,providing evidence to assist in controlling the spread and proliferation of ARGs and MRGs in activated sludge systems.
基金This work was financially supported by the National Natural Science Foundation of China(Grant No.41877131)Taishan Scholars Program of Shandong Province(No.tsqn201812116)+2 种基金Science and Technology Service Network Initiative of the Chinese Academy of Sciences(KFJ-STS-QYZX-114)Two-Hundred Talents Plan of Yantai(No.Y739011021)Wanhua Chemical Group Co.Ltd。
文摘Microplastics existing widely in different matrices have been regarded as a reservoir for emerging contaminants.Mariculture systems have been observed to host microplastics and antibiotic resistance genes(ARGs).However,more information on proliferation of ARGs and metal resistance genes(MRGs)in mariculture system at the presence of microplastics is needed.This study used metagenomic analysis to investigate the distribution of ARGs and MRGs in water and microplastics of a typical mariculture pond.Total 18 types including 174 subtypes of ARGs were detected with the total relative abundances of 1.22/1.25 copies per 16S rRNA copy for microplastics/water.Chloramphenicol resistance genes were the dominant ARGs with the abundance of 0.35/0.42 copies per 16S rRNA copy for microplastics/water.Intergron intI1 was dominant gene among 6 detected mobile genetic elements(MGEs)with the abundance of 75.46/68.70 copies per 16S rRNA copy for water/microplastics.Total 9 types including 46 subtypes of MRGs were detected with total abundance of 5.02×10^(2)/6.39×10^(2)copies per 16S rRNA copy for water/microplastics while genes resistant to copper and iron served as the dominant MRGs.Proteobacteria,Bacteroidetes,and Actinobacteria accounted for 84.2%/89.5%of total microbial community in microplastics/water.ARGs with relatively high abundance were significantly positively related to major genera,MGEs,and MRGs.Microplastics in mariculture system could enrich most of MRGs and some ARGs to serve as potential reservoir for these pollutants.The findings of this study will provide important information on resistance gene pollution at presence of microplastics in the mariculture system for further proposing suitable strategy of environmental management.
