Mercury(Hg),especially methylmercury(MeHg),accumulation in rice grain due to rice paddy possessing conditions conducive to Hg methylation has led to human Hg exposure through consumption of rice-based daily meals.In a...Mercury(Hg),especially methylmercury(MeHg),accumulation in rice grain due to rice paddy possessing conditions conducive to Hg methylation has led to human Hg exposure through consumption of rice-based daily meals.In addition to being a food staple,rice is widely used as a raw material to produce a vast variety of processed food products.Little is known about Hg levels in snacking rice-food products and potential Hg exposure from consumption of them,besides previous studies on infant rice cereals.Aiming to provide complementary information for a more complete assessment on Hg exposure risk originated from Hgcontaining rice,this study determined total Hg(THg)and MeHg levels in 195 rice-containing and rice-free processed food products covering all major types of snack foods marketed in China and the estimated daily intake(EDI)of dietary Hg from the consumption of these foods.The results clearly showed THg and MeHg contents in rice-containing foods were significantly higher than rice-free products,suggesting the transfer of Hg and MeHg from the rice to the end products,even after manufacturing processes.Moreover,significant positive correlations were observed between THg,MeHg,or MeHg/THg ratio and rice content for samples containing multiple grains as ingredients,further indicating the deciding role of rice for Hg levels in the end food products.Although the EDI of THg and MeHg via ricebased food products were relatively low compared to the reference dose,it should be considered these snacking food products would contribute additive Hg intake outside of the daily regular meals.展开更多
The high-pressure mercury intrusion (HPMI) experiment is widely used to assess the pore architecture oftight sandstone reservoirs. However, the conventional analysis of the high- pressure mercury intrusionhas always f...The high-pressure mercury intrusion (HPMI) experiment is widely used to assess the pore architecture oftight sandstone reservoirs. However, the conventional analysis of the high- pressure mercury intrusionhas always focused on the mercury injection curves themselves, neglecting the important geologicalinformation conveyed by the mercury ejection curves. This paper quantitatively describes the fractalcharacteristics of ejection curves by using four fractal models, i.e.,. Menger model, Thermodynamicmodel, Sierpinski model, and multi- fractal model. In comparison with mercury injection curves, weexplore the fractal significance of mercury ejection curves and define the applicability of different fractalmodels in characterizing pore architectures. Investigated tight sandstone samples can be divided intofour types (Types A, B, C and D) based on porosity, permeability, and mercury removal efficiency. Type Dsamples are unique in that they have higher permeability (>0.6 mD) but lower mercury removal effi-ciency (<35%). Fractal studies of the mercury injection curve show that it mainly reflects the pore throatcharacteristics, while the mercury ejection curve serves to reveal the pore features, and porosity andpermeability correlate well with the fractal dimension of the injection curve, while mercury removalefficiency correlates only with the Ds' value of the ejection curve. The studies on the mercury ejectioncurves also reveal that the small pores and micropores of the Type C and Type D samples are moredeveloped, with varying pore architecture. The fractal dimension Ds' value of Type D samples is greaterthan that of Type C samples, and the dissolution of Type D samples is more intense than that of Type Csamples, which further indicates that the Type D samples are smaller in pore size, rougher in surface, andwith greater difficulty for the hydrocarbon to enter, resulting in their reservoir capacity probably lessthan that of Type C samples. In this regard, the important information characterized by the mercuryejection curve should be considered in evaluating the tight sandstone reservoirs. Finally, the Menger andThermodynamic models prove to be more suitable for describing the total pore architecture, while theSierpinski model is better for characterizing the variability of the interconnected pores.展开更多
Mercury removal from coal combustion flue gas remains a significant challenge for environmental protection due to the lack of cost-effective sorbents.In this study,a series of red mud(RM)-based sorbents impregnated wi...Mercury removal from coal combustion flue gas remains a significant challenge for environmental protection due to the lack of cost-effective sorbents.In this study,a series of red mud(RM)-based sorbents impregnated with sodium halides(NaBr and NaI)are presented to capture elemental mercury(Hg^(0))from flue gas.The modified RM underwent comprehensive characterization,including analysis of its textural qualities,crystal structure,chemical composition,and thermal properties.The results indicate that the halide impregnation substantially impacts the surface area and pore size of the RM.Hg^(0) removal performance was evaluated on a fixed-bed reactor in simulated flue gas(consisting of N_(2),O_(2),CO_(2),NO and SO_(2),etc.)on a modified RM.At an optimal adsorption temperature of 160℃,NaI-modified sorbent(RMI5)offers a removal efficiency of 98%in a mixture of gas,including O_(2),NO and HCl.Furthermore,pseudo-second-order model fitting results demonstrate the chemisorption mechanism for the adsorption of Hg^(0) in kinetic investigations.展开更多
Since scarce knowledge of soil mercury(Hg)concentrations and risks in the vulnerable Xinjiang,topsoils(0-15 cm)from its typical landscapes were extensively sampled.Topsoil total mercury(THg)concentrations varied broad...Since scarce knowledge of soil mercury(Hg)concentrations and risks in the vulnerable Xinjiang,topsoils(0-15 cm)from its typical landscapes were extensively sampled.Topsoil total mercury(THg)concentrations varied broadly between 0.9 and 35.3 ng/g,of which16.8%exceeded the background value of soil Hg for Xinjiang.Topsoil THg concentrations across various landscapes exhibited a declining order:farmland(11.7±6.0 ng/g)>grassland(10.5±8.5 ng/g)>woodland(10.2±8.2 ng/g)>desert(7.0±5.8 ng/g).The average topsoil THg concentration was higher in northwestern Xinjiang(11.3±7.2 ng/g)than that in southeastern Xinjiang(6.3±6.1 ng/g).Relatively high topsoil THg concentrations were observed near the cities with intensive human activities,followed by a gradual decline to the surroundings.The concentrations of topsoil THg were strongly correlated with the contents of total organic carbon(TOC),clay,silty,and sandy,and the distance from each sampling site to its nearest city,suggesting that the variation of topsoil Hg was significantly influenced by TOC content,soil granularity,and anthropogenic Hg emissions.Silty and TOC were the principal affecting factors,explaining 48.7%and 7.9%of the THg variation,respectively.The contamination and potential ecological risk evaluations revealed that topsoils in regions with dense populations were polluted with Hg and contained higher potential ecological risks.The health risk evaluations indicated that exposure risks of topsoil Hg were higher for children than those for adults.Fortunately,topsoil Hg posed acceptable risks to human health.展开更多
Carbon-supported mercury catalysts are extensivelyemployed in calcium carbide-based polyvinyl chloride(PVC)industries,but the usage of mercury-based catalysts can pose an environmental threat due to the release of mer...Carbon-supported mercury catalysts are extensivelyemployed in calcium carbide-based polyvinyl chloride(PVC)industries,but the usage of mercury-based catalysts can pose an environmental threat due to the release of mercury into the surrounding area during the operation period.In this study,a highly active and stable mercury-based catalyst was developed,utilizing the nitrogen atom of the support as the anchor site to enhance the interaction between active sites(HgCl_(2))and the carbon support(N-AC).Thermal loss rate testing and thermogravimetric analysis results demonstrate that,compared to commercial activated carbon,N-doped carbon can effectively increase the heat stability of HgCl_(2).The obtained mercury-based catalysts(HgCl_(2)/N-AC)exhibit significant catalytic performance,achieving 2.5 times the C2H2 conversion of conventional HgCl_(2)/AC catalysts.Experimental analysis combined with theoretical calculations reveals that,contrary to the Eley-Rideal(ER)mechanism of HgCl_(2)/AC,the HgCl_(2)/N-AC catalyst follows the Langmuir-Hinshelwood(LH)adsorption mechanism.The nitrogen sites and HgCl_(2) on the catalyst enhance the adsorption capabilities of the HCl and C2H2,thereby improving the catalytic performance.Based on the modification of the active center by these solid ligands,the loading amount of HgCl_(2) on the catalyst can be further reduced from the current 6.5%to 3%.Considering the absence of successful industrial applications for mercury-free catalysts,and based on the current annual consumption of commercial mercury chloride catalysts in the PVC industry,the widespread adoption of this technology could annually reduce the usage of chlorine mercury by 500 tons,making a notable contribution to mercury compliance,reduction,and emissions control in China.It also serves as a bridge between mercury-free and low-mercury catalysts.Moreover,this solid ligand technology can assist in the application research of mercury-free catalysts.展开更多
The pore structure of rocks significantly influences the porosity and permeability of reservoirs and the migration ability of oil and gas,and being the key task on the development of volcanic gas reservoirs.Nine volca...The pore structure of rocks significantly influences the porosity and permeability of reservoirs and the migration ability of oil and gas,and being the key task on the development of volcanic gas reservoirs.Nine volcanic rock samples from the Yingcheng Formation and Huoshiling Formation in the Longfengshan area of the Changling Fault Depression in the Songliao Basin were selected for this study.The pore structures of the volcanic rocks in the study area were investigated using high-pressure mercury injection,X-ray diffraction combined with fractal theory.The relationships between the fractal dimension and physical properties characteristics,pore structure parameters,and mineral content were analyzed to provide guidance for the development of volcanic rock gas reservoirs.The results show that the reservoir can be divided into 3 types(I,II,and III)based on the shape of the capillary pressure curve,and the physical properties deteriorate successively.Different types of reservoirs exhibit different fractal characteristics.For typesⅠ,ⅡandⅢ,the average total fractal dimensions were 2.3418,2.6850,and 2.9203,respectively.The larger the fractal dimension,the stronger the heterogeneity of reservoir.A small number of macro-pores primarily contributed to permeability.The fractal dimension was negatively correlated with porosity and permeability.The fractal dimension of the rock was strongly correlated with quartz and feldspar contents,and the mineral composition and content are closely related to the pore evolution of the reservoir,which are the internal factors affecting the fractal dimension of volcanic rock.展开更多
This study used steel slag,fly ash,and metakaolin as raw materials(SFM materials)to create silica-alumina-based geopolymers that can solidify Hg^(2+)when activated with sodiumbased water glass.The experiments began wi...This study used steel slag,fly ash,and metakaolin as raw materials(SFM materials)to create silica-alumina-based geopolymers that can solidify Hg^(2+)when activated with sodiumbased water glass.The experiments began with a triangular lattice point mixing design experiment,and the results were fitted,analyzed,and predicted.The optimum SFM material mass ratio was found to be 70%steel slag,25%fly ash,and 5%metakaolin.The optimum modulus of the activator was identified by comparing the unconfined compressive strength and solidifying impact on Hg^(2+)of geosynthetics with different modulus.The SFM geopolymer was then applied in the form of potting to cure the granulated mercury tailings.The inclusion of 50%SFM material generated a geosynthetic that reduced mercury transport to the surface soil by roughly 90%.The mercury concentration of herbaceous plant samples was also reduced by 78%.It indicates that the SFM material can effectively attenuate the migration transformation of mercury.Finally,characterization methods such as XPS and FTIR were used to investigate the mechanism of Hg^(2+)solidification by geopolymers generated by SFM materials.The possible solidification mechanisms were proposed as alkaline environment-induced mercury precipitation,chemical bonding s,surface adsorption of Hg^(2+)and its precipitates by the geopolymer,and physical encapsulation.展开更多
Mercury(Hg)pollution has been a global concern in recent decades,posing a significant threat to entire ecosystems and human health due to its cumulative toxicity,persistence,and transport in the atmosphere.The intense...Mercury(Hg)pollution has been a global concern in recent decades,posing a significant threat to entire ecosystems and human health due to its cumulative toxicity,persistence,and transport in the atmosphere.The intense interaction between mercury and selenium has opened up a new field for studying mercury removal from industrial flue gas pollutants.Besides the advantages of good Hg^(0) capture performance and lowsecondary pollution of the mineral selenium compounds,the most noteworthy is the relatively low regeneration temperature,allowing adsorbent regeneration with low energy consumption,thus reducing the utilization cost and enabling recovery of mercury resources.This paper reviews the recent progress of mineral selenium compounds in flue gas mercury removal,introduces in detail the different types ofmineral selenium compounds studied in the field ofmercury removal,reviews the adsorption performance of various mineral selenium compounds adsorbents on mercury and the influence of flue gas components,such as reaction temperature,air velocity,and other factors,and summarizes the adsorption mechanism of different fugitive forms of selenium species.Based on the current research progress,future studies should focus on the economic performance and the performance of different carriers and sizes of adsorbents for the removal of Hg^(0) and the correlation between the gas-particle flow characteristics and gas phase mass transfer with the performance of Hg^(0) removal in practical industrial applications.In addition,it remains a challenge to distinguish the oxidation and adsorption of Hg^(0) quantitatively.展开更多
Metal-organic frameworks(MOFs)attract broad interests in mercury(Hg)ion adsorption field,while unreasonable distribution of active groups commonly restricts their utilization efficiency.In this work,we constructed a n...Metal-organic frameworks(MOFs)attract broad interests in mercury(Hg)ion adsorption field,while unreasonable distribution of active groups commonly restricts their utilization efficiency.In this work,we constructed a new MOF(TYUST-6)with dense thiol-rich traps in the 1D pore wall.This accessible channel and rational distribution of thiols allow the smooth diffusion of Hg ions and thereby result in a high Langmuir adsorption capacity of 1347.6 mg/g,almost reaching the theoretical maximum(1444.3 mg/g).Adsorption equilibrium needs 10 and 30 min at the initial concentrations of 10 and 100 mg/L,respectively.Common co-existing ions and solution pH show almost negligible interferences on the adsorption,and adsorbent regeneration can be well achieved.Combining experimental characterizations and theoretical calculations,the thiol groups in the pore wall are proved to be the dominant interaction sites.Thus,this work reports a novel high-capacity adsorbent for Hg^(2+),and proposes a feasible guideline for designing effective adsorbents.展开更多
Objective This study investigated the impact of occupational mercury(Hg) exposure on human gene transcription and expression, and its potential biological mechanisms.Methods Differentially expressed genes related to H...Objective This study investigated the impact of occupational mercury(Hg) exposure on human gene transcription and expression, and its potential biological mechanisms.Methods Differentially expressed genes related to Hg exposure were identified and validated using gene expression microarray analysis and extended validation. Hg-exposed cell models and PTEN lowexpression models were established in vitro using 293T cells. PTEN gene expression was assessed using qRT-PCR, and Western blotting was used to measure PTEN, AKT, and PI3K protein levels. IL-6 expression was determined by ELISA.Results Combined findings from gene expression microarray analysis, bioinformatics, and population expansion validation indicated significant downregulation of the PTEN gene in the high-concentration Hg exposure group. In the Hg-exposed cell model(25 and 10 μmol/L), a significant decrease in PTEN expression was observed, accompanied by a significant increase in PI3K, AKT, and IL-6 expression.Similarly, a low-expression cell model demonstrated that PTEN gene knockdown led to a significant decrease in PTEN protein expression and a substantial increase in PI3K, AKT, and IL-6 levels.Conclusion This is the first study to report that Hg exposure downregulates the PTEN gene, activates the PI3K/AKT regulatory pathway, and increases the expression of inflammatory factors, ultimately resulting in kidney inflammation.展开更多
Mercury is a threatening pollutant in food,herein,we developed a Tb^(3+)-nucleic acid probe-based label-free assay for mix-and-read,rapid detection of mercury pollution.The assay utilized the feature of light-up fluor...Mercury is a threatening pollutant in food,herein,we developed a Tb^(3+)-nucleic acid probe-based label-free assay for mix-and-read,rapid detection of mercury pollution.The assay utilized the feature of light-up fluorescence of terbium ions(Tb^(3+))via binding with single-strand DNA.Mercury ion,Hg^(2+)induced thymine(T)-rich DNA strand to form a double-strand structure(T-Hg^(2+)-T),thus leading to fluorescence reduction.Based on the principle,Hg^(2+)can be quantified based on the fluorescence of Tb^(3+),the limit of detection was 0.0689μmol/L and the linear range was 0.1-6.0μmol/L.Due to the specificity of T-Hg^(2+)-T artificial base pair,the assay could distinguish Hg^(2+)from other metal ions.The recovery rate was ranged in 98.71%-101.34%for detecting mercury pollution in three food samples.The assay is low-cost,separation-free and mix-to-read,thus was a competitive tool for detection of mercury pollution to ensure food safety.展开更多
The interest in curtailing environmental pollution issues through physical separation processes has inspired an extensive search for novel nanoporous materials with exceptional adsorption capabilities.Covalent triazin...The interest in curtailing environmental pollution issues through physical separation processes has inspired an extensive search for novel nanoporous materials with exceptional adsorption capabilities.Covalent triazine frameworks(CTFs),emerged as a class of crystalline covalent organic frameworks(COFs),have been widely examined for various separation applications,owing to their large porosity,high stability,and rich nitrogen(N)doping.The development of CTFs for efficient adsorption of mercury(Ⅱ)(Hg^(2+))is of great importance for the field,whereas it is rarely attempted,on account of limited synthetic strategies and unknown structural-property relations of conventional CTFs derived from ionothermal approaches.Herein,we report rational synthesis of a crystalline CTF with methylthio pendant arms for efficient removal of Hg^(2+)with an exceptional capacity of 751 mg·g^(-1),ranking at the top among previously-reported adsorbents.This work may open up new possibility in the synthesis of COFs for various separations.展开更多
Mercury(Hg)is one of the most dangerous contaminants and has sparked global concern since it poses a health risk to humans when consumed through rice.Sulfur(S)is a crucial component for plant growth,and S may reduce H...Mercury(Hg)is one of the most dangerous contaminants and has sparked global concern since it poses a health risk to humans when consumed through rice.Sulfur(S)is a crucial component for plant growth,and S may reduce Hg accumulation in rice grains.However,the detailed effects of S and the mechanisms underlying S-mediated responses in Hg-stressed rice plants remain unclear.Currently,to investigate the effects of S addition on rice growth,Hg accumulation,physiological indexes,and gene expression profiles,rice seedlings were hydroponically treated with Hg(20μmol/L Hg Cl_(2))and Hg plus elemental sulfur(100 mg/L).S application significantly reduced Hg accumulation in Hg-stressed rice roots and alleviated the inhibitory effects of Hg on rice growth.S addition significantly reduced Hg-induced reactive oxygen species generation,membrane lipid peroxidation levels,and activities of antioxidant enzymes while increasing glutathione content in leaves.Transcriptomic analysis of roots identified 3,411,2,730,and 581 differentially expressed genes in the control(CK)vs.Hg,CK vs.Hg+S,and Hg vs.Hg+S datasets,respectively.The pathway of S-mediated biological metabolism fell into six groups:biosynthesis and metabolism,expression regulation,transport,stimulus response,oxidation reduction,and cell wall biogenesis.The majority of biological process-related genes were upregulated under Hg stress compared with CK treatment,but downregulated in the Hg+S treatment.The results provide transcriptomic and physiological evidence that S may be critical for plant Hg stress resistance and will help to develop strategies for reduction or phytoremediation of Hg contamination.展开更多
Ultra-low emission(ULE)technology retrofits significantly impact the particulate-bound mercury(Hg)emissions from coal-fired power plants(CFPPs);however,the distribution and bioavailability of Hg in size-fractioned par...Ultra-low emission(ULE)technology retrofits significantly impact the particulate-bound mercury(Hg)emissions from coal-fired power plants(CFPPs);however,the distribution and bioavailability of Hg in size-fractioned particulate matter(PM)around the ULE-retrofitted CF-PPs are less understood.Here,total Hg and its chemical speciation in TSP(total suspended particles),PM_(10)(aerodynamic particle diameter≤10μm)and PM_(2.5)(aerodynamic particle diameter≤2.5μm)around a ULE-retrofitted CFPP in Guizhou Province were quantified.Atmospheric PM_(2.5)concentration was higher around this ULE-retrofitted CFPP than that in the intra-regional urban cities,and it had higher mass Hg concentration than other sizefractioned PM.Total Hg concentrations in PM had multifarious sources including CFPP,vehicle exhaust and biomass combustion,while they were significantly higher in autumn and winter than those in other seasons(P<0.05).Regardless of particulate size,atmospheric PM-bound Hg had lower residual fractions(<21%)while higher HCl-soluble fractions(>40%).Mass concentrations of exchangeable,HCl-soluble,elemental,and residual Hg in PM_(2.5)were higher than those in other size-fractioned PM,and were markedly elevated in autumn and winter(P<0.05).In PM_(2.5),HCl-soluble Hg presented a significantly positive relationship with elemental Hg(P<0.05),while residual Hg showed the significantly positive relationships with HCl-soluble Hg and elemental Hg(P<0.01).Overall,these results suggested that atmospheric PM-bound Hg around the ULE-retrofitted CFPP tends to accumulate in finer PM,and has higher bioavailable fractions,while has potential transformation between chemical speciation.展开更多
Pre-combustion mercury removal via coal electrolysis was performed and investigated on a bench-scale coal electrolytic cell(CEC)systemically,and factorial design was used to determine the effect of different operating...Pre-combustion mercury removal via coal electrolysis was performed and investigated on a bench-scale coal electrolytic cell(CEC)systemically,and factorial design was used to determine the effect of different operating conditions(coal particle size,operating temperature,operating cell voltage,and flow rate of slurry)on the percentage of mercury removal,percentage of ash removal,and dry heating value change.The results showed that the operating cell voltage,as well as the interaction between operating cell voltage and coal particle size,are significant factors in the percentage of mercury removal.There is no significant factor in the percentage of ash removal and the dry heating value change,but the coal could be purified while keeping the dry heating value almost constant after electrolysis.A co-product of hydrogen could be produced during coal electrolysis with 50%lower energy consumption compared with water electrolysis.Meanwhile,a mechanism for mercury removal in coal was proposed.The facts indicate that coal electrolysis is a promising method for precombustion mercury removal.展开更多
Oxy-combustion is a promising carbon-capture technology,but atmospheric-pressure oxy-combustion has a relatively low net efficiency,limiting its application in power plants.In pressurized oxycombustion(POC),the boiler...Oxy-combustion is a promising carbon-capture technology,but atmospheric-pressure oxy-combustion has a relatively low net efficiency,limiting its application in power plants.In pressurized oxycombustion(POC),the boiler,air separation unit,flue gas recirculation unit,and CO_(2)purification and compression unit are all operated at elevated pressure;this makes the process more efficient,with many advantages over atmospheric pressure,such as low NO_(x)emissions,a smaller boiler size,and more.POC is also more promising for industrial application and has attracted widespread research interest in recent years.It can produce high-pressure CO_(2)with a purity of approximately 95%,which can be used directly for enhanced oil recovery or geo-sequestration.However,the pollutant emissions must meet the standards for carbon capture,storage,and utilization.Because of the high oxygen and moisture concentrations in POC,the formation of acids via the oxidation and solution of SO_(x)and NO_(x)can be increased,causing the corrosion of pipelines and equipment.Furthermore,particulate matter(PM)and mercury emissions can harm the environment and human health.The main distinction between pressurized and atmospheric-pressure oxy-combustion is the former’s elevated pressure;thus,the effect of this pressure on the pollutants emitted from POC—including SO_(x),NO_(x),PM,and mercury—must be understood,and effective control methodologies must be incorporated to control the formation of these pollutants.This paper reviews recent advances in research on SO_(x),NO_(x),PM,and mercury formation and control in POC systems that can aid in pollutant control in such systems.展开更多
Space weathering is a primary factor in altering the composition and spectral characteristics of surface materials on airless planets.However,current research on space weathering focuses mainly on the Moon and certain...Space weathering is a primary factor in altering the composition and spectral characteristics of surface materials on airless planets.However,current research on space weathering focuses mainly on the Moon and certain types of asteroids.In particular,the impacts of meteoroids and micrometeoroids,radiation from solar wind/solar flares/cosmic rays,and thermal fatigue due to temperature variations are being studied.Space weathering produces various transformation products such as melted glass,amorphous layers,iron particles,vesicles,and solar wind water.These in turn lead to soil maturation,changes in visible and near-infrared reflectance spectra(weakening of characteristic absorption peaks,decreased reflectance,increased near-infrared slope),and alterations in magnetism(related to small iron particles),collectively termed the“lunar model”of space weathering transformation.Compared to the Moon and asteroids,Mercury has unique spatial environmental characteristics,including more intense meteoroid impacts and solar thermal radiation,as well as a weaker particle radiation environment due to the global distribution of its magnetic field.Therefore,the lunar model of space weathering may not apply to Mercury.Previous studies have extensively explored the eff ects of micrometeoroid impacts.Hence,this work focuses on the eff ects of solar-wind particle radiation in global magnetic-field distribution and on the weathering transformation of surface materials on Mercury under prolonged intense solar irradiation.Through the utilization of highvalence state,heavy ion implantation,and vacuum heating simulation experiments,this paper primarily investigates the weathering transformation characteristics of the major mineral components such as anorthite,pyroxene,and olivine on Mercury’s surface and compares them to the weathering transformation model of the Moon.The experimental results indicate that ion implantation at room temperature is insufficient to generate np-Fe^(0)directly but can facilitate its formation,while prolonged exposure to solar thermal radiation on Mercury’s surface can lead directly to the formation of np-Fe^(0).Therefore,intense solar thermal radiation is a crucial component of the unique space weathering transformation process on Mercury’s surface.展开更多
The tree ring has been regarded as an emerging archive to reconstruct historical atmospheric mercury(Hg)trends,but with the large knowledge gaps in the reliability.In this study,we comprehensively evaluated the Hg sou...The tree ring has been regarded as an emerging archive to reconstruct historical atmospheric mercury(Hg)trends,but with the large knowledge gaps in the reliability.In this study,we comprehensively evaluated the Hg source,radial translocation and age effect of Masson pine(Pinus massoniana)tree ring at Mt.Jinyun in Chongqing,to assess the suitability of such tree ring as the archive of atmospheric Hg.Results showed that distinct variabilities among Masson pine tree-ring Hg concentration profiles.The Hg concentration significantly increased along with stem height(P<0.05),indicating the Hg in tree rings mainly derived from foliage uptake atmospheric Hg.We found a distinct age effect that the tree ring of young trees had the higher Hg concentration.Besides,we used the advection-diffusion model to demonstrate how Hg concentration shifted by the advection or/and diffusion in tree rings.The modeling results showed that the advection induced radial translocation during the young growth period of tree was a plausible mechanism to result in the tree-ring Hg record largely different from the trend of anthropogenic Hg emissions in Chongqing.We finally suggest that in further Hg dendrochemistry,better discarding the tree-ring Hg profile of the young growth period to reduce impacts of the radial translocation and age effect.展开更多
基金supported by the Shandong Provincial Natural Science Foundation (No.ZR2022QB242)the National Natural Science Foundation of China (No.22306111 and 22306108)+1 种基金the Shandong Provincial Natural Science Foundation (No.ZR2020ZD20)the Chinese Postdoctoral Science Foundation (No.2023M732059).
文摘Mercury(Hg),especially methylmercury(MeHg),accumulation in rice grain due to rice paddy possessing conditions conducive to Hg methylation has led to human Hg exposure through consumption of rice-based daily meals.In addition to being a food staple,rice is widely used as a raw material to produce a vast variety of processed food products.Little is known about Hg levels in snacking rice-food products and potential Hg exposure from consumption of them,besides previous studies on infant rice cereals.Aiming to provide complementary information for a more complete assessment on Hg exposure risk originated from Hgcontaining rice,this study determined total Hg(THg)and MeHg levels in 195 rice-containing and rice-free processed food products covering all major types of snack foods marketed in China and the estimated daily intake(EDI)of dietary Hg from the consumption of these foods.The results clearly showed THg and MeHg contents in rice-containing foods were significantly higher than rice-free products,suggesting the transfer of Hg and MeHg from the rice to the end products,even after manufacturing processes.Moreover,significant positive correlations were observed between THg,MeHg,or MeHg/THg ratio and rice content for samples containing multiple grains as ingredients,further indicating the deciding role of rice for Hg levels in the end food products.Although the EDI of THg and MeHg via ricebased food products were relatively low compared to the reference dose,it should be considered these snacking food products would contribute additive Hg intake outside of the daily regular meals.
基金The research project was co-funded by the National Natural Science Foundation of China(No.42072172,No.41772120)Shandong Province Natural Science Fund for Distinguished Young Scholars(No.JQ201311)the Graduate Scientific and Technological Innovation Project Financially Supported by Shandong University of Science and Technology(No.SDKDYC190313).
文摘The high-pressure mercury intrusion (HPMI) experiment is widely used to assess the pore architecture oftight sandstone reservoirs. However, the conventional analysis of the high- pressure mercury intrusionhas always focused on the mercury injection curves themselves, neglecting the important geologicalinformation conveyed by the mercury ejection curves. This paper quantitatively describes the fractalcharacteristics of ejection curves by using four fractal models, i.e.,. Menger model, Thermodynamicmodel, Sierpinski model, and multi- fractal model. In comparison with mercury injection curves, weexplore the fractal significance of mercury ejection curves and define the applicability of different fractalmodels in characterizing pore architectures. Investigated tight sandstone samples can be divided intofour types (Types A, B, C and D) based on porosity, permeability, and mercury removal efficiency. Type Dsamples are unique in that they have higher permeability (>0.6 mD) but lower mercury removal effi-ciency (<35%). Fractal studies of the mercury injection curve show that it mainly reflects the pore throatcharacteristics, while the mercury ejection curve serves to reveal the pore features, and porosity andpermeability correlate well with the fractal dimension of the injection curve, while mercury removalefficiency correlates only with the Ds' value of the ejection curve. The studies on the mercury ejectioncurves also reveal that the small pores and micropores of the Type C and Type D samples are moredeveloped, with varying pore architecture. The fractal dimension Ds' value of Type D samples is greaterthan that of Type C samples, and the dissolution of Type D samples is more intense than that of Type Csamples, which further indicates that the Type D samples are smaller in pore size, rougher in surface, andwith greater difficulty for the hydrocarbon to enter, resulting in their reservoir capacity probably lessthan that of Type C samples. In this regard, the important information characterized by the mercuryejection curve should be considered in evaluating the tight sandstone reservoirs. Finally, the Menger andThermodynamic models prove to be more suitable for describing the total pore architecture, while theSierpinski model is better for characterizing the variability of the interconnected pores.
基金supported by the National Natural Science Foundation of China(22278066,21776039)the National Key R&D Program of China(2023YFB4103001)The Fundamental Research Funds for the Central Universities(DUT2021TB03).
文摘Mercury removal from coal combustion flue gas remains a significant challenge for environmental protection due to the lack of cost-effective sorbents.In this study,a series of red mud(RM)-based sorbents impregnated with sodium halides(NaBr and NaI)are presented to capture elemental mercury(Hg^(0))from flue gas.The modified RM underwent comprehensive characterization,including analysis of its textural qualities,crystal structure,chemical composition,and thermal properties.The results indicate that the halide impregnation substantially impacts the surface area and pore size of the RM.Hg^(0) removal performance was evaluated on a fixed-bed reactor in simulated flue gas(consisting of N_(2),O_(2),CO_(2),NO and SO_(2),etc.)on a modified RM.At an optimal adsorption temperature of 160℃,NaI-modified sorbent(RMI5)offers a removal efficiency of 98%in a mixture of gas,including O_(2),NO and HCl.Furthermore,pseudo-second-order model fitting results demonstrate the chemisorption mechanism for the adsorption of Hg^(0) in kinetic investigations.
基金supported by the Second Tibetan Plateau Scientific Expedition and Research Program(STEP)(No.2019QZKK0605)the National Natural Science Foundation of China(No.42201161)the Startup Foundation for Introducing Talent of NUIST(No.2022r024)。
文摘Since scarce knowledge of soil mercury(Hg)concentrations and risks in the vulnerable Xinjiang,topsoils(0-15 cm)from its typical landscapes were extensively sampled.Topsoil total mercury(THg)concentrations varied broadly between 0.9 and 35.3 ng/g,of which16.8%exceeded the background value of soil Hg for Xinjiang.Topsoil THg concentrations across various landscapes exhibited a declining order:farmland(11.7±6.0 ng/g)>grassland(10.5±8.5 ng/g)>woodland(10.2±8.2 ng/g)>desert(7.0±5.8 ng/g).The average topsoil THg concentration was higher in northwestern Xinjiang(11.3±7.2 ng/g)than that in southeastern Xinjiang(6.3±6.1 ng/g).Relatively high topsoil THg concentrations were observed near the cities with intensive human activities,followed by a gradual decline to the surroundings.The concentrations of topsoil THg were strongly correlated with the contents of total organic carbon(TOC),clay,silty,and sandy,and the distance from each sampling site to its nearest city,suggesting that the variation of topsoil Hg was significantly influenced by TOC content,soil granularity,and anthropogenic Hg emissions.Silty and TOC were the principal affecting factors,explaining 48.7%and 7.9%of the THg variation,respectively.The contamination and potential ecological risk evaluations revealed that topsoils in regions with dense populations were polluted with Hg and contained higher potential ecological risks.The health risk evaluations indicated that exposure risks of topsoil Hg were higher for children than those for adults.Fortunately,topsoil Hg posed acceptable risks to human health.
基金supported by the National Key Research and Development Program of China(2024YFC3907904).
文摘Carbon-supported mercury catalysts are extensivelyemployed in calcium carbide-based polyvinyl chloride(PVC)industries,but the usage of mercury-based catalysts can pose an environmental threat due to the release of mercury into the surrounding area during the operation period.In this study,a highly active and stable mercury-based catalyst was developed,utilizing the nitrogen atom of the support as the anchor site to enhance the interaction between active sites(HgCl_(2))and the carbon support(N-AC).Thermal loss rate testing and thermogravimetric analysis results demonstrate that,compared to commercial activated carbon,N-doped carbon can effectively increase the heat stability of HgCl_(2).The obtained mercury-based catalysts(HgCl_(2)/N-AC)exhibit significant catalytic performance,achieving 2.5 times the C2H2 conversion of conventional HgCl_(2)/AC catalysts.Experimental analysis combined with theoretical calculations reveals that,contrary to the Eley-Rideal(ER)mechanism of HgCl_(2)/AC,the HgCl_(2)/N-AC catalyst follows the Langmuir-Hinshelwood(LH)adsorption mechanism.The nitrogen sites and HgCl_(2) on the catalyst enhance the adsorption capabilities of the HCl and C2H2,thereby improving the catalytic performance.Based on the modification of the active center by these solid ligands,the loading amount of HgCl_(2) on the catalyst can be further reduced from the current 6.5%to 3%.Considering the absence of successful industrial applications for mercury-free catalysts,and based on the current annual consumption of commercial mercury chloride catalysts in the PVC industry,the widespread adoption of this technology could annually reduce the usage of chlorine mercury by 500 tons,making a notable contribution to mercury compliance,reduction,and emissions control in China.It also serves as a bridge between mercury-free and low-mercury catalysts.Moreover,this solid ligand technology can assist in the application research of mercury-free catalysts.
基金Supported by Key Scientific and Technological Projects of Sinopec(No.P21104-2).
文摘The pore structure of rocks significantly influences the porosity and permeability of reservoirs and the migration ability of oil and gas,and being the key task on the development of volcanic gas reservoirs.Nine volcanic rock samples from the Yingcheng Formation and Huoshiling Formation in the Longfengshan area of the Changling Fault Depression in the Songliao Basin were selected for this study.The pore structures of the volcanic rocks in the study area were investigated using high-pressure mercury injection,X-ray diffraction combined with fractal theory.The relationships between the fractal dimension and physical properties characteristics,pore structure parameters,and mineral content were analyzed to provide guidance for the development of volcanic rock gas reservoirs.The results show that the reservoir can be divided into 3 types(I,II,and III)based on the shape of the capillary pressure curve,and the physical properties deteriorate successively.Different types of reservoirs exhibit different fractal characteristics.For typesⅠ,ⅡandⅢ,the average total fractal dimensions were 2.3418,2.6850,and 2.9203,respectively.The larger the fractal dimension,the stronger the heterogeneity of reservoir.A small number of macro-pores primarily contributed to permeability.The fractal dimension was negatively correlated with porosity and permeability.The fractal dimension of the rock was strongly correlated with quartz and feldspar contents,and the mineral composition and content are closely related to the pore evolution of the reservoir,which are the internal factors affecting the fractal dimension of volcanic rock.
基金supported by the National Key R&D Projects of China(No.2018YFC1801706-01)the National Natural Science Foundation of China(No.22162007)+2 种基金the Science and Technology Supporting Project of Guizhou Province(No.[2021]480,[2023]379)the Wengfu(Group)Co.,Ltd.Technology Development Project(No.WH-220787(YF))the Project from Guizhou Institute of Innovation and Development of Dual-carbon and New Energy Technologies(No.DCRE-2023-05)。
文摘This study used steel slag,fly ash,and metakaolin as raw materials(SFM materials)to create silica-alumina-based geopolymers that can solidify Hg^(2+)when activated with sodiumbased water glass.The experiments began with a triangular lattice point mixing design experiment,and the results were fitted,analyzed,and predicted.The optimum SFM material mass ratio was found to be 70%steel slag,25%fly ash,and 5%metakaolin.The optimum modulus of the activator was identified by comparing the unconfined compressive strength and solidifying impact on Hg^(2+)of geosynthetics with different modulus.The SFM geopolymer was then applied in the form of potting to cure the granulated mercury tailings.The inclusion of 50%SFM material generated a geosynthetic that reduced mercury transport to the surface soil by roughly 90%.The mercury concentration of herbaceous plant samples was also reduced by 78%.It indicates that the SFM material can effectively attenuate the migration transformation of mercury.Finally,characterization methods such as XPS and FTIR were used to investigate the mechanism of Hg^(2+)solidification by geopolymers generated by SFM materials.The possible solidification mechanisms were proposed as alkaline environment-induced mercury precipitation,chemical bonding s,surface adsorption of Hg^(2+)and its precipitates by the geopolymer,and physical encapsulation.
基金supported by the Basic Research Business Fund Grant Program for University of Science and Technology Beijing (No.06500227)the Fundamental Research Funds for the Central Universities (No.FRF-TP-22-091A1).
文摘Mercury(Hg)pollution has been a global concern in recent decades,posing a significant threat to entire ecosystems and human health due to its cumulative toxicity,persistence,and transport in the atmosphere.The intense interaction between mercury and selenium has opened up a new field for studying mercury removal from industrial flue gas pollutants.Besides the advantages of good Hg^(0) capture performance and lowsecondary pollution of the mineral selenium compounds,the most noteworthy is the relatively low regeneration temperature,allowing adsorbent regeneration with low energy consumption,thus reducing the utilization cost and enabling recovery of mercury resources.This paper reviews the recent progress of mineral selenium compounds in flue gas mercury removal,introduces in detail the different types ofmineral selenium compounds studied in the field ofmercury removal,reviews the adsorption performance of various mineral selenium compounds adsorbents on mercury and the influence of flue gas components,such as reaction temperature,air velocity,and other factors,and summarizes the adsorption mechanism of different fugitive forms of selenium species.Based on the current research progress,future studies should focus on the economic performance and the performance of different carriers and sizes of adsorbents for the removal of Hg^(0) and the correlation between the gas-particle flow characteristics and gas phase mass transfer with the performance of Hg^(0) removal in practical industrial applications.In addition,it remains a challenge to distinguish the oxidation and adsorption of Hg^(0) quantitatively.
基金supported by the National Natural Science Foundation of China(No.22208230)Fundamental Research Program of Shanxi Province(No.202103021223281)。
文摘Metal-organic frameworks(MOFs)attract broad interests in mercury(Hg)ion adsorption field,while unreasonable distribution of active groups commonly restricts their utilization efficiency.In this work,we constructed a new MOF(TYUST-6)with dense thiol-rich traps in the 1D pore wall.This accessible channel and rational distribution of thiols allow the smooth diffusion of Hg ions and thereby result in a high Langmuir adsorption capacity of 1347.6 mg/g,almost reaching the theoretical maximum(1444.3 mg/g).Adsorption equilibrium needs 10 and 30 min at the initial concentrations of 10 and 100 mg/L,respectively.Common co-existing ions and solution pH show almost negligible interferences on the adsorption,and adsorbent regeneration can be well achieved.Combining experimental characterizations and theoretical calculations,the thiol groups in the pore wall are proved to be the dominant interaction sites.Thus,this work reports a novel high-capacity adsorbent for Hg^(2+),and proposes a feasible guideline for designing effective adsorbents.
基金supported by the Jiangsu Province’s Outstanding Medical Academic Leader Program [CXTDA2017029]the Jiangsu Provincial Key Medical Discipline [ZDXK202249].
文摘Objective This study investigated the impact of occupational mercury(Hg) exposure on human gene transcription and expression, and its potential biological mechanisms.Methods Differentially expressed genes related to Hg exposure were identified and validated using gene expression microarray analysis and extended validation. Hg-exposed cell models and PTEN lowexpression models were established in vitro using 293T cells. PTEN gene expression was assessed using qRT-PCR, and Western blotting was used to measure PTEN, AKT, and PI3K protein levels. IL-6 expression was determined by ELISA.Results Combined findings from gene expression microarray analysis, bioinformatics, and population expansion validation indicated significant downregulation of the PTEN gene in the high-concentration Hg exposure group. In the Hg-exposed cell model(25 and 10 μmol/L), a significant decrease in PTEN expression was observed, accompanied by a significant increase in PI3K, AKT, and IL-6 expression.Similarly, a low-expression cell model demonstrated that PTEN gene knockdown led to a significant decrease in PTEN protein expression and a substantial increase in PI3K, AKT, and IL-6 levels.Conclusion This is the first study to report that Hg exposure downregulates the PTEN gene, activates the PI3K/AKT regulatory pathway, and increases the expression of inflammatory factors, ultimately resulting in kidney inflammation.
基金financially supported by National Natural Science Foundation of China(22074100)the Young Elite Scientist Sponsorship Program by CAST(YESS20200036)+3 种基金the Researchers Supporting Project Number RSP-2021/138King Saud University,Riyadh,Saudi ArabiaTechnological Innovation R&D Project of Chengdu City(2019-YF05-31702266-SN)Sichuan University-Panzhihua City joint Project(2020CDPZH-5)。
文摘Mercury is a threatening pollutant in food,herein,we developed a Tb^(3+)-nucleic acid probe-based label-free assay for mix-and-read,rapid detection of mercury pollution.The assay utilized the feature of light-up fluorescence of terbium ions(Tb^(3+))via binding with single-strand DNA.Mercury ion,Hg^(2+)induced thymine(T)-rich DNA strand to form a double-strand structure(T-Hg^(2+)-T),thus leading to fluorescence reduction.Based on the principle,Hg^(2+)can be quantified based on the fluorescence of Tb^(3+),the limit of detection was 0.0689μmol/L and the linear range was 0.1-6.0μmol/L.Due to the specificity of T-Hg^(2+)-T artificial base pair,the assay could distinguish Hg^(2+)from other metal ions.The recovery rate was ranged in 98.71%-101.34%for detecting mercury pollution in three food samples.The assay is low-cost,separation-free and mix-to-read,thus was a competitive tool for detection of mercury pollution to ensure food safety.
基金The National Natural Science Foundation of China(22078349,22005319,52170109)Self-deployment Program from Lanzhou Institute of Chemical Physics(E30159SQ).
文摘The interest in curtailing environmental pollution issues through physical separation processes has inspired an extensive search for novel nanoporous materials with exceptional adsorption capabilities.Covalent triazine frameworks(CTFs),emerged as a class of crystalline covalent organic frameworks(COFs),have been widely examined for various separation applications,owing to their large porosity,high stability,and rich nitrogen(N)doping.The development of CTFs for efficient adsorption of mercury(Ⅱ)(Hg^(2+))is of great importance for the field,whereas it is rarely attempted,on account of limited synthetic strategies and unknown structural-property relations of conventional CTFs derived from ionothermal approaches.Herein,we report rational synthesis of a crystalline CTF with methylthio pendant arms for efficient removal of Hg^(2+)with an exceptional capacity of 751 mg·g^(-1),ranking at the top among previously-reported adsorbents.This work may open up new possibility in the synthesis of COFs for various separations.
基金supported by the National Natural Science Foundation of China (Nos.42030702 and 41877143)the Guangdong Key Research and Development Project (No.2019B110207002)the Local Innovative and Research Teams Project of the Guangdong Pearl River Talents Program (No.2017BT01Z176)。
文摘Mercury(Hg)is one of the most dangerous contaminants and has sparked global concern since it poses a health risk to humans when consumed through rice.Sulfur(S)is a crucial component for plant growth,and S may reduce Hg accumulation in rice grains.However,the detailed effects of S and the mechanisms underlying S-mediated responses in Hg-stressed rice plants remain unclear.Currently,to investigate the effects of S addition on rice growth,Hg accumulation,physiological indexes,and gene expression profiles,rice seedlings were hydroponically treated with Hg(20μmol/L Hg Cl_(2))and Hg plus elemental sulfur(100 mg/L).S application significantly reduced Hg accumulation in Hg-stressed rice roots and alleviated the inhibitory effects of Hg on rice growth.S addition significantly reduced Hg-induced reactive oxygen species generation,membrane lipid peroxidation levels,and activities of antioxidant enzymes while increasing glutathione content in leaves.Transcriptomic analysis of roots identified 3,411,2,730,and 581 differentially expressed genes in the control(CK)vs.Hg,CK vs.Hg+S,and Hg vs.Hg+S datasets,respectively.The pathway of S-mediated biological metabolism fell into six groups:biosynthesis and metabolism,expression regulation,transport,stimulus response,oxidation reduction,and cell wall biogenesis.The majority of biological process-related genes were upregulated under Hg stress compared with CK treatment,but downregulated in the Hg+S treatment.The results provide transcriptomic and physiological evidence that S may be critical for plant Hg stress resistance and will help to develop strategies for reduction or phytoremediation of Hg contamination.
基金supported by the Science and Technology Project of Guizhou Province(No.QKHJC[2020]1Y187)the National Natural Science Foundation of China(Nos.41265008,42007305,and 22166009)。
文摘Ultra-low emission(ULE)technology retrofits significantly impact the particulate-bound mercury(Hg)emissions from coal-fired power plants(CFPPs);however,the distribution and bioavailability of Hg in size-fractioned particulate matter(PM)around the ULE-retrofitted CF-PPs are less understood.Here,total Hg and its chemical speciation in TSP(total suspended particles),PM_(10)(aerodynamic particle diameter≤10μm)and PM_(2.5)(aerodynamic particle diameter≤2.5μm)around a ULE-retrofitted CFPP in Guizhou Province were quantified.Atmospheric PM_(2.5)concentration was higher around this ULE-retrofitted CFPP than that in the intra-regional urban cities,and it had higher mass Hg concentration than other sizefractioned PM.Total Hg concentrations in PM had multifarious sources including CFPP,vehicle exhaust and biomass combustion,while they were significantly higher in autumn and winter than those in other seasons(P<0.05).Regardless of particulate size,atmospheric PM-bound Hg had lower residual fractions(<21%)while higher HCl-soluble fractions(>40%).Mass concentrations of exchangeable,HCl-soluble,elemental,and residual Hg in PM_(2.5)were higher than those in other size-fractioned PM,and were markedly elevated in autumn and winter(P<0.05).In PM_(2.5),HCl-soluble Hg presented a significantly positive relationship with elemental Hg(P<0.05),while residual Hg showed the significantly positive relationships with HCl-soluble Hg and elemental Hg(P<0.01).Overall,these results suggested that atmospheric PM-bound Hg around the ULE-retrofitted CFPP tends to accumulate in finer PM,and has higher bioavailable fractions,while has potential transformation between chemical speciation.
基金Chemical and Biomolecular Engineering Department in Ohio University。
文摘Pre-combustion mercury removal via coal electrolysis was performed and investigated on a bench-scale coal electrolytic cell(CEC)systemically,and factorial design was used to determine the effect of different operating conditions(coal particle size,operating temperature,operating cell voltage,and flow rate of slurry)on the percentage of mercury removal,percentage of ash removal,and dry heating value change.The results showed that the operating cell voltage,as well as the interaction between operating cell voltage and coal particle size,are significant factors in the percentage of mercury removal.There is no significant factor in the percentage of ash removal and the dry heating value change,but the coal could be purified while keeping the dry heating value almost constant after electrolysis.A co-product of hydrogen could be produced during coal electrolysis with 50%lower energy consumption compared with water electrolysis.Meanwhile,a mechanism for mercury removal in coal was proposed.The facts indicate that coal electrolysis is a promising method for precombustion mercury removal.
基金support of the National Key Research and Development Program of China(2022YFE0206600)the National Natural Science Foundation of China(52376125)Fundamental Research Funds for the Central Universities.
文摘Oxy-combustion is a promising carbon-capture technology,but atmospheric-pressure oxy-combustion has a relatively low net efficiency,limiting its application in power plants.In pressurized oxycombustion(POC),the boiler,air separation unit,flue gas recirculation unit,and CO_(2)purification and compression unit are all operated at elevated pressure;this makes the process more efficient,with many advantages over atmospheric pressure,such as low NO_(x)emissions,a smaller boiler size,and more.POC is also more promising for industrial application and has attracted widespread research interest in recent years.It can produce high-pressure CO_(2)with a purity of approximately 95%,which can be used directly for enhanced oil recovery or geo-sequestration.However,the pollutant emissions must meet the standards for carbon capture,storage,and utilization.Because of the high oxygen and moisture concentrations in POC,the formation of acids via the oxidation and solution of SO_(x)and NO_(x)can be increased,causing the corrosion of pipelines and equipment.Furthermore,particulate matter(PM)and mercury emissions can harm the environment and human health.The main distinction between pressurized and atmospheric-pressure oxy-combustion is the former’s elevated pressure;thus,the effect of this pressure on the pollutants emitted from POC—including SO_(x),NO_(x),PM,and mercury—must be understood,and effective control methodologies must be incorporated to control the formation of these pollutants.This paper reviews recent advances in research on SO_(x),NO_(x),PM,and mercury formation and control in POC systems that can aid in pollutant control in such systems.
基金supported by the Strategic Priority Research Program of the Chinese Academy of Sciences(XDB 41000000)the National Natural Science Foundation of China(42273042 and 41931077)+1 种基金the Youth Innovation Promotion Association,the Chinese Academy of Sciences(2020395)the Guizhou Provincial Science and Technology Projects(QKHJC-ZK[2023]-General 473).
文摘Space weathering is a primary factor in altering the composition and spectral characteristics of surface materials on airless planets.However,current research on space weathering focuses mainly on the Moon and certain types of asteroids.In particular,the impacts of meteoroids and micrometeoroids,radiation from solar wind/solar flares/cosmic rays,and thermal fatigue due to temperature variations are being studied.Space weathering produces various transformation products such as melted glass,amorphous layers,iron particles,vesicles,and solar wind water.These in turn lead to soil maturation,changes in visible and near-infrared reflectance spectra(weakening of characteristic absorption peaks,decreased reflectance,increased near-infrared slope),and alterations in magnetism(related to small iron particles),collectively termed the“lunar model”of space weathering transformation.Compared to the Moon and asteroids,Mercury has unique spatial environmental characteristics,including more intense meteoroid impacts and solar thermal radiation,as well as a weaker particle radiation environment due to the global distribution of its magnetic field.Therefore,the lunar model of space weathering may not apply to Mercury.Previous studies have extensively explored the eff ects of micrometeoroid impacts.Hence,this work focuses on the eff ects of solar-wind particle radiation in global magnetic-field distribution and on the weathering transformation of surface materials on Mercury under prolonged intense solar irradiation.Through the utilization of highvalence state,heavy ion implantation,and vacuum heating simulation experiments,this paper primarily investigates the weathering transformation characteristics of the major mineral components such as anorthite,pyroxene,and olivine on Mercury’s surface and compares them to the weathering transformation model of the Moon.The experimental results indicate that ion implantation at room temperature is insufficient to generate np-Fe^(0)directly but can facilitate its formation,while prolonged exposure to solar thermal radiation on Mercury’s surface can lead directly to the formation of np-Fe^(0).Therefore,intense solar thermal radiation is a crucial component of the unique space weathering transformation process on Mercury’s surface.
基金supported by the Natural Science Foundation of Chongqing(No.cstc2020jcyj-msxmX0063)the National Natural Science Foundation of China(No.41977272)。
文摘The tree ring has been regarded as an emerging archive to reconstruct historical atmospheric mercury(Hg)trends,but with the large knowledge gaps in the reliability.In this study,we comprehensively evaluated the Hg source,radial translocation and age effect of Masson pine(Pinus massoniana)tree ring at Mt.Jinyun in Chongqing,to assess the suitability of such tree ring as the archive of atmospheric Hg.Results showed that distinct variabilities among Masson pine tree-ring Hg concentration profiles.The Hg concentration significantly increased along with stem height(P<0.05),indicating the Hg in tree rings mainly derived from foliage uptake atmospheric Hg.We found a distinct age effect that the tree ring of young trees had the higher Hg concentration.Besides,we used the advection-diffusion model to demonstrate how Hg concentration shifted by the advection or/and diffusion in tree rings.The modeling results showed that the advection induced radial translocation during the young growth period of tree was a plausible mechanism to result in the tree-ring Hg record largely different from the trend of anthropogenic Hg emissions in Chongqing.We finally suggest that in further Hg dendrochemistry,better discarding the tree-ring Hg profile of the young growth period to reduce impacts of the radial translocation and age effect.
