Airborne microplastics(MPs)are important pollutants that have been present in the environment for many years and are characterized by their universality,persistence,and potential toxicity.This study investigated the e...Airborne microplastics(MPs)are important pollutants that have been present in the environment for many years and are characterized by their universality,persistence,and potential toxicity.This study investigated the effects of terrestrial and marine transport of MPs in the atmosphere of a coastal city and compared the difference between daytime and nighttime.Laser direct infrared imaging(LDIR)and polarized light microscopy were used to characterize the physical and chemical properties of MPs,including number concentration,chemical types,shape,and size.Backward trajectories were used to distinguish the air masses from marine and terrestrial transport.Twenty chemical types were detected by LDIR,with rubber(16.7%)and phenol-formaldehyde resin(PFR;14.8%)being major components.Three main morphological types of MPs were identified,and fragments(78.1%)are the dominant type.MPs in the atmosphere were concentrated in the small particle size segment(20-50μm).The concentration of MPs in the air mass from marine transport was 14.7 items/m^(3)-lower than that from terrestrial transport(32.0 items/m^(3)).The number concentration of airborne MPs was negatively correlated with relative humidity.MPs from terrestrial transport were mainly rubber(20.2%),while those from marine transport were mainly PFR(18%).MPs in the marine transport air mass were more aged and had a lower number concentration than those in the terrestrial transport air mass.The number concentration of airborne MPs is higher during the day than at night.These findings could contribute to the development of targeted control measures and methods to reduce MP pollution.展开更多
An intense Asian dust storm invadedQinhuangdao,a coastal city ofNorth China on April 11-14,2023.We analyzed the bulk water-soluble inorganic ions(WSII)of PM_(10)and PM_(2.5)using an Ion Chromatograph and investigated ...An intense Asian dust storm invadedQinhuangdao,a coastal city ofNorth China on April 11-14,2023.We analyzed the bulk water-soluble inorganic ions(WSII)of PM_(10)and PM_(2.5)using an Ion Chromatograph and investigated individual particlemorphology and elemental composition using a scanning electron microscope coupled with energy dispersive X-ray.The results showed when the dust was directly transported to the sampling site from northwestern China(direct transport stages),the PM_(10)mass concentrations were high(675.0μg/m^(3))but the relative humidity(RH)was low.Total WSII were 19.54μg/m^(3)and 11.17μg/m^(3),accounting for 2.90%and 7.25%of the PM_(10)and PM_(2.5),respectively.In addition,the proportion of S-containing individual mineral dust was low(28.7%-35.3%).The results suggested there were limited secondary inorganic aerosol formation.However,when the dust was transported back to the sampling site across the Bohai Sea in the following days(reverse transport stages),both the PM_(10)mass concentrations(462.3μg/m^(3))and RH were high.Total WSII were 43.75μg/m^(3)and 18.71μg/m^(3),accounting for 9.62%and 14.45%of the total PM_(10)and PM_(2.5),respectively.The proportion of S-containing particles was 51.5%-72.5%.In addition,the concentration of NO_(3)^(−)was much higher than that of SO_(4)^(2−).The results suggested both the sulfate and nitrate formation occurred on coarse mineral dust but the nitrate formation exceeded sulfate formation.Interestingly,mostmineral dust,including Sirich particles contained Cl when they passed through the marine atmosphere.The results highlighted the heterogeneous reactions of dust varied in different transport stages.展开更多
There are 9 major coal-accumulating periods during geological history in China,including the Early Carboniferous,Late Carboniferous-Early Permian,Middle Permian,Late Permian,Late Triassic,Early-Middle Jurassic,Early C...There are 9 major coal-accumulating periods during geological history in China,including the Early Carboniferous,Late Carboniferous-Early Permian,Middle Permian,Late Permian,Late Triassic,Early-Middle Jurassic,Early Cretaceous,Paleogene and Neogene.The coal formed in these periods were developed in different coal-accumulating areas(CAA)including the North China,South China,Northwest China,Northeast China,the Qinghai–Tibet area,and China offshore area.In this paper,we investigated depositional environments,sequence stratigraphy,lithofacies paleogeography and coal accumulation pattern of five major coal-accumulating periods including the Late Carboniferous to Middle Permian of the North China CAA,the Late Permian of the South China CAA,the Late Triassic of the South China CAA,the Early-Middle Jurassic of the North and Northwest China CAA,and the Early Cretaceous in the Northeast China CAA.According to distribution of the coal-bearing strata and the regional tectonic outlines,we have identified distribution range of the coal-forming basins,sedimentary facies types and coal-accumulating models.The sequence stratigraphic frameworks of the major coal-accumulating periods were established based on recognition of a variety of sequence boundaries.The distribution of thick coals and migration patterns of the coal-accumulating centers in the sequence stratigraphic framework were analyzed.The lithofacies paleogeography maps based on third-order sequences were reconstructed and the distribution of coal accumulation centers and coal-rich belts were predicted.展开更多
Aerosol samples were collected in summer in Macao, a coastal city of the Pearl River Delta Region in China. Morphology, size, elemental composition, and mixing state of individual aerosol particles were determined by ...Aerosol samples were collected in summer in Macao, a coastal city of the Pearl River Delta Region in China. Morphology, size, elemental composition, and mixing state of individual aerosol particles were determined by scanning electron microscopy coupled energy dispersive X-ray （SEM/EDX） and transmission electron microscopy （TEM）. Based on the morphologies of 5711 aerosol particles, they consist of soot （32%）, mineral （17%）, secondary-（22%）, and unknown fine particles （29%）. The sizes of these particles were mostly distributed between 0.1 and 0.4 μm. Compositions of 202 mineral particles were obtained by SEM/EDX. Mineral particles were mainly classified into three types： Si-rich, Ca-rich, and Na-rich. The compositions of typical mineral particles can indicate their sources in sampling location. For example, mineral particles, collected along the main street, were associated with trace amounts of heavy metals, such as Zn, Ti, Mn, Ba, Pb, and As. TEM observations indicate that most Na-rich particles were aged sea salt particles （e.g., Na2SO4 and NaNO3） which formed through heterogeneous chemical reactions between sea salt and acidic gases. Additionally, aging time of soot was short in Macao due to high humidity, high temperature, and high levels of sunlight in Macao. Most of soot and fine mineral dust particles were internally mixed with secondary particles.展开更多
As one of the most important source rocks and reservoirs of unconventional natural gas, the sedimentary environment and mode of peat swamp（the predecessor of coal seam） is important to the coal seam＇s spatial distr...As one of the most important source rocks and reservoirs of unconventional natural gas, the sedimentary environment and mode of peat swamp（the predecessor of coal seam） is important to the coal seam＇s spatial distribution, material composition, hydrocarbon generation potential, reservoir physical properties, etc. To reveal the depositional characteristics and history of environmental change in a terrestrial basin during a period of peat accumulation, the Middle Jurassic aged #7 coal from Gaoquan in the Qaidam Basin（NW China） was investigated using sedimentology, maceral composition, geochemistry and sequence stratigraphy. Based on identification of the sedimentary shoreline break belt, wave energy depletion point and position of wave base, the peat swamp system can be subdivided into（1） lakeside plain,（2） low energy lakeshore,（3） high energy lakeshore, and（4） shallow lake subfacies. A new method for determining coal facies is proposed based on the combination of environmental parameters including oxidation-reduction levels, energy conditions and the influence of terrigneous sediments. The evolution of the coal seam shows that peat was deposited mainly in the low energy lakeshore and lakeside plain subfacies. Five types of sequence stratigrpahic surface and two types of parasequence were identified. Forced lake regressions and normal lake regressions are attributed as the causes of sequence boundaries. The sequence stratigraphic framework comprises six sequences and corresponding system tracts, and the curve of base-level for each demonstrates a characteristic initial period of slow rising followed by fast rising and then returning to slow rising. A model indicating the relationship among base-level changes, coal facies evolution, and the environmental features in the swamp is proposed that shows the environmental features of the swamp were controlled by both base-level changes and coal facies. Accompanying depositional environment changes from a lakeside plain to lakeshore and shallow lake caused by increasing rate of base-level rise, water paleosalinity, acidity and the percentage of woody plants decrease, and the bog type alters from the low marsh to raised bog.展开更多
Traffic vehicles, many of which are powered by port fuel injection(PFI) engines, are major sources of particulate matter in the urban atmosphere. We studied particles from the emission of a commercial PFI-engine vehic...Traffic vehicles, many of which are powered by port fuel injection(PFI) engines, are major sources of particulate matter in the urban atmosphere. We studied particles from the emission of a commercial PFI-engine vehicle when it was running under the states of cold start, hot start, hot stabilized running, idle and acceleration, using a transmission electron microscope and an energy-dispersive X-ray detector. Results showed that the particles were mainly composed of organic, soot, and Ca-rich particles, with a small amount of S-rich and metal-containing particles, and displayed a unimodal size distribution with the peak at 600 nm. The emissions were highest under the cold start running state, followed by the hot start, hot stabilized, acceleration, and idle running states. Organic particles under the hot start and hot stabilized running states were higher than those of other running states. Soot particles were highest under the cold start running state. Under the idle running state, the relative number fraction of Ca-rich particles was high although their absolute number was low. These results indicate that PFI-engine vehicles emit substantial primary particles,which favor the formation of secondary aerosols via providing reaction sites and reaction catalysts, as well as supplying soot, organic, mineral and metal particles in the size range of the accumulation mode. In addition, the contents of Ca, P, and Zn in organic particles may serve as fingerprints for source apportionment of particles from PFI-engine vehicles.展开更多
Coal correlation cannot only guide coal and coalbed methane exploitation,but may also provide valuable information for the evolution of the paleoclimate and paleoenvironment during coalaccumulation periods.It is diffi...Coal correlation cannot only guide coal and coalbed methane exploitation,but may also provide valuable information for the evolution of the paleoclimate and paleoenvironment during coalaccumulation periods.It is difficult to undertake coal correlation in a terrestrial basin due to multiple superimposed coal seams and a lack of effective marker beds.In this study,based on the analyses of coal-bearing sedimentary environments and the observations of field outcrops and drilling cores,three key sequence surfaces of the Middle Jurassic Xishanyao Formation were identified in the middle part of the southern Junggar Basin.Three third-order sequences(S.Ⅲ1,S.Ⅲ2 and S.Ⅲ3)and ten fourth-order sequences were divided within the Xishanyao Formation.Regional coal correlation was finally identified,combined with the layered vertical pattern coal and its interval thickness,coal maceral,and coal quality data.In terms of the coal correlation within a specific sequence set,the interval of the B2–B3 coals was approximately three times thicker than that of the B3–B5 coals,which was the main marker for regional coal correlation in the Lower Xishanyao Formation.Furthermore,the phenomena of steadily developed B4 coal seam(2–3 m in thickness)across the Liuhuanggou coal mining area(eastern study region)and the large-small-large variation for intervals between the B8 and B9,B9 and B10,and B10 and B11 coal seams in the Manasi coal mining(western study region)were also an effective means for local coal correlation.Increasing vitrinite and sulphur content and decreasing inertinite content in a third-order sequence were found,which were likely to be closely related to lake level fluctuations.Based on the variation of coal macerals,the wildfire frequency gradually decreased from the bottom to the top of the Xishanyao Formation.The predicted O2level of the S.Ⅲ1,S.Ⅲ2,and S.Ⅲ3 of the Xishanyao Formation was 26.36%,24.22%,and 22.51%,respectively.Except for global paleoclimate effects,the provenance direction changes caused by the Bogda Mountains uplifts would result in a regular variation of coal maceral and coal quality across the study region.展开更多
Epidemiological studies have suggested that inhalation exposure to indoor ambient air from coal-burning environments is causally associated with respiratory health risks.In order to explore the toxicological mechanism...Epidemiological studies have suggested that inhalation exposure to indoor ambient air from coal-burning environments is causally associated with respiratory health risks.In order to explore the toxicological mechanisms behind the adverse health effects,the hemolytic activity of PM_(10)(particulate matter with an aerodynamic diameter of 10 um or less)samples collected from homes burning coal in the recognized China"cancer village"Xuanwei were evaluated and matched against their trace elemental contents.The results demonstrated that the hemolytic activity of indoor PM_(10) in coal-burning environments ranged from 4.28%to 5.24%,with a clear positive dose-response relationship.Although low dose samples exhibited a reduced hemolytic activity,PM_(10) could have a toxic effect upon people in a coal-burning indoor environment for extended time periods.The concentrations of analyzed trace elements in PM_(10) samples ranged from 6966 to 12,958 ppm.Among the analyzed elements,Zn,Ti,Ni,Cu,Pb,Ba,Mn,Cr and V were found at higher concentrations and accounted for over 95%of the total elements.The concentrations of total analyzed elements in the PM_(10) samples revealed a significant positive correlation with PM_(10) hemolytic activity.Of the analyzed elements,Zn,Pb and Cs positively correlated with hemolysis,while Li,U and V negatively correlated with the hemolysis of human red blood cells(RBCs).Therefore,the heavy metal elements could be one of the main factors responsible for the hemolytic capacity of indoor PM_(10) in coal-burning environments.展开更多
Coal combustion in the domestic stoves, which is common in most parts of the Chinese countryside, can release harmful substances into the air and cause health issues. In this study, particles emitted from laboratory s...Coal combustion in the domestic stoves, which is common in most parts of the Chinese countryside, can release harmful substances into the air and cause health issues. In this study, particles emitted from laboratory stove combustion of the raw powder coals were analyzed for morphologies and chemical compositions by using transmission electron microscopy （TEM） coupled with energy-dispersive X-ray spectrometry （EDX）. The coal burning-derived individual particles were classified into two groups： carbonaceous particles （including soot aggregates and organic particles） and non-carbonaceous particles （including sulfate, mineral and metal particles）. The non-carbonaceous particles, which constituted a majority of the coal burning-derived emissions, were subdivided into Si-rich, S-rich, K-rich, Ca-rich, and Fe-rich particles according to the elemental compositions. The Si-rich, S-rich and K-rich particles are commonly observed in the coal burning emission. The proportions for particles of different types exhibit obvious coal-issue dependence. Burning of coal with high ash yield could emit more non-carbonaceous particles, and burning of coal with high sulfur content can emit more S-rich particles. By comparing the S-rich particles from this coal burning experiment with those in the atmosphere, we draw a conclusion that some S-rich particles in the atmosphere in China could be mainly sourced from coal combustion.展开更多
Corona Virus Disease 2019(COVID-19)caused by the novel coronavirus,results in an acute respiratory condition coronavirus 2(SARS-CoV-2)and is highly infectious.The recent spread of this virus has caused a global pandem...Corona Virus Disease 2019(COVID-19)caused by the novel coronavirus,results in an acute respiratory condition coronavirus 2(SARS-CoV-2)and is highly infectious.The recent spread of this virus has caused a global pandemic.Currently,the transmission routes of SARS-CoV-2 are being established,especially the role of environmental transmission.Here we review the environmental transmission routes and persistence of SARS-CoV-2.Recent studies have established that the transmission of this virus may occur,amongst others,in the air,water,soil,cold-chain,biota,and surface contact.It has also been found that the survival potential of the SARS-CoV-2 virus is dependent on different environmental conditions and pollution.Potentially important pathways include aerosol and fecal matter.Particulate matter may also be a carrier for SARS-CoV-2.Since microscopic particles can be easily absorbed by humans,more attention must be focused on the dissemination of these particles.These considerations are required to evolve a theoretical platform for epidemic control and to minimize the global threat from future epidemics.展开更多
The frequent haze days around the Chinese capital of Beijing in recent years have aroused great attention owing to the detrimental effects on visibility and public health. To discover the potential health effects of t...The frequent haze days around the Chinese capital of Beijing in recent years have aroused great attention owing to the detrimental effects on visibility and public health. To discover the potential health effects of the haze, oxidative capacities of airborne particles collected in Beijing during haze and clear days were comparably assessed by a plasmid scission assay. Eleven water-soluble trace elements （As, Cd, Cr, Cu, Mn, Ni, Pb, V, Se, T1, and Zn） in the size-segregated airborne particles were quantitatively analyzed by inductively coupled plasma mass spectrometry, and most of the water- soluble trace elements were found to mainly concentrate in the fine particle size of 0.56-1.0 μm. In comparison with clear days, the mass concentrations of 11 analyzed water-soluble trace elements remarkably increased during haze days, and the oxidative capacities determined by the plasmid scission assay were markedly elevated accordingly during the haze days under the same dosage of particles as for those during clear days. Water-soluble trace elements in airborne particles, such as Cu, V, and particularly Zn, were found to have significantly positive correlations with the plasmid DNA damage rates. Because Cu, V, and Zn have been considered as bioavailable elements, the evident increase of these elements during haze days may be greatly harmful to human health.展开更多
The Early Cretaceous is an important coal accumulation period in China.Abundant coal resources were formed in the southeastern margin of Songliao Basin.Sequence stratigraphy and coal accumulation of the Early Cretaceo...The Early Cretaceous is an important coal accumulation period in China.Abundant coal resources were formed in the southeastern margin of Songliao Basin.Sequence stratigraphy and coal accumulation of the Early Cretaceous in the southeastern margin of Songliao Basin have been studied on the basis of extensive outcrop and borehole data.Based on regional unconformity,basal erosional surfaces of incised valley fills,and abrupt depositional facies-reversal surface,six sequence boundaries have been identified,which subdivide the Early Cretaceous coal-bearing series into 5 third-order sequences.Sequence I corresponds to Huoshiling Formation,sequences II and III correspond to member I and member II of Shahezi Formation.Sequences IV and V correspond to member I and member II of Yingcheng Formation.Sequence I developed at the initial subsiding stage,sequence II and III developed during the stable subsiding stage,while sequence IV and V developed during the basin shrinkage stage.The major coal seams were developed in the sequence II and III,which ensured the relative balance between the increase rate of the accommodation space and the rate of peat accumulation for a longer period,thus forming a thick coal seam.展开更多
A severe Asian Dust Storm(ADS)event occurred on April 16-17th,2006 in northem China.Mineral components of dust samples were analyzed using X-ray diffraction(XRD).The result indicates that dust particles were dominated...A severe Asian Dust Storm(ADS)event occurred on April 16-17th,2006 in northem China.Mineral components of dust samples were analyzed using X-ray diffraction(XRD).The result indicates that dust particles were dominated by quartz(37.4%)and clay(32.9%),followed by plagioclase(13.7%),with small amounts of calcite,K-feldspar,dolomite,homblende,and gypsum(all【10%).展开更多
Emission from burning coals is one of the major sources of the airborne particles in China.We carried out a study on the rare earth elements(REEs)in the inhalable particulate matter(PM10)emitted from burning coals and...Emission from burning coals is one of the major sources of the airborne particles in China.We carried out a study on the rare earth elements(REEs)in the inhalable particulate matter(PM10)emitted from burning coals and soil-coal honeycomb briquettes with different volatile contents and ash yields in a combustion-dilution system.Gravimetric analysis indicates that the equivalent mass concentration of the PM10 emitted from burning the coals is higher than that emitted from burning the briquettes.The ICP-MS analysis indicates that the contents of total REEs in the coal-burning PM10 are lower than those in the briquetteburning PM10.In addition,the contents of the light rare earth elements(LREEs)are higher than those of the heavy rare earth elements(HREEs)in the PM10 emitted from burning the coals and briquettes,demonstrating that the REEs in both the coal-burning and briquetteburning PM10 are dominated by LREEs.The higher contents of total REEs and LREEs in the coal-burning PM10 are associated with the higher ash yields and lower volatile contents in the raw coals.A comparative analysis indicates that the La/Sm ratios in the PM10 emitted from burning the coals and briquettes,being lower than 2,are lower than those in the particles from gasoline-powered vehicle emission.展开更多
Previous studies of coal sequence stratigraphy have concentrated on coals associated with paralic depositional systems.Little attention has been paid to their counterparts in non-marine intra-mountain coal basins.The ...Previous studies of coal sequence stratigraphy have concentrated on coals associated with paralic depositional systems.Little attention has been paid to their counterparts in non-marine intra-mountain coal basins.The northern Qaidam Basin of northwestern China has been extensively developed with abundant oil and gas as well as coal resources in its Jurassic non-marine successions.展开更多
This paper analyses the sequence stratigraphy and palaeogeography of the Early and early Middle Jurassic coal measures in the Turpan-Hami Basin,northwestern China.The controls of the palaeogeography and sequence strat...This paper analyses the sequence stratigraphy and palaeogeography of the Early and early Middle Jurassic coal measures in the Turpan-Hami Basin,northwestern China.The controls of the palaeogeography and sequence stratigraphy on the coal accumulation in this basin have been discussed.The results show that the coal measures were formed in a fluvial-delta-lacustrine sedimentary system,and a total of 4 third-order sequences were developed.展开更多
The Qinshui Basin in southeastern Shanxi Province is an important base for coalbed methane exploration and production in China.The methane reservoirs in this area are the Carboniferous and Permian coals and their thic...The Qinshui Basin in southeastern Shanxi Province is an important base for coalbed methane exploration and production in China.The methane reservoirs in this area are the Carboniferous and Permian coals and their thickness are strongly controlled by the depositional environments and the sequence stratigraphic framework.This paper analyzes the high-resolution sequence stratigraphy of the Permo-Carbo-niferous Taiyuan and Shanxi Formations.展开更多
The northern type Longtan Formation of the Late Permian in central Hunan is dominated by an assemblage of greyish black mudstone,siltstone,sandy mudstone,fine sandstone and coals,and contains a variety of sedimentary ...The northern type Longtan Formation of the Late Permian in central Hunan is dominated by an assemblage of greyish black mudstone,siltstone,sandy mudstone,fine sandstone and coals,and contains a variety of sedimentary structures such as thin sandstone-mudstone interbedded bedding,flaser beddings,lenticular beddings.展开更多
Based on analyses of the lithofacies palaeo-geography of the Taiyuan and the Shanxi Formations in the Qinshui Basin, the spatial variations of the coal seam thickness, coal maceral composition, coal quality, and gas c...Based on analyses of the lithofacies palaeo-geography of the Taiyuan and the Shanxi Formations in the Qinshui Basin, the spatial variations of the coal seam thickness, coal maceral composition, coal quality, and gas content, together with the lithofacies of the surrounding rocks in each palaeogeographic unit were investigated. The results show that the thick coals of the Taiyuan Formation are mainly distributed in delta and barrier island depositional units in the Yangquan area in the northern part of the basin and the Zhangzi area in the southeastern part of the basin. The thick coals of the Shanxi Formation are located within transitional areas between delta plain and delta front depositional units in the central southern part of the basin. The Taiyuan Formation generally includes mudstone in its lower part, thick, continuous coal seams and limestones in its middle part, and thin, discontinuous coal seams and limestone and sand-mud interbeds in its top part. The Shanxi Formation consists of thick, continuous sandstones in its lower part, thick coal seams in its middle part, and thin coal seams, sandstone, and thick mudstone in its upper part. From the perspective of coal-bearing sedimentology and coalbed methane (CBM) geology, the lithology and thickness of the surrounding rocks of coal seams play more significant roles in controlling gas content variation than other factors such as coal thickness, coal macerals, and coal quality. Furthermore, it is found that the key factors influencing the gas content variation are the thicknesses of mudstone and limestone overlying a coal seam. At similar burial depths, the gas content of the Taiyuan coal seams decreases gradually in the lower delta plain, barrier-lagoon,delta front, barrier-tidal flat, and carbonate platform depositional units. The CBM enrichment areas tend to be located in zones of poorly developed limestone and well-developed mudstone. In addition, the gas content of the Shanxi Formation is higher in the coals of the delta front facies compared to those in the lower delta plain. The CBM enrichment areas tend to be associated with the thicker mudstones. Therefore, based on the lithologic distribution and thickness of the rocks overlying the coal seam in each palaeogeographic unit of the Taiyuan and Shanxi Formations, the areas with higher gas content are located in the north-central basin for the Taiyuan coals and in the southern basin for the Shanxi coals. Both of these areas should be favorable for CBM exploration in the Qinshui Basin.展开更多
基金supported by the National Natural Science Foundation of China (No.42075107)the Fundamental Research Funds for the Central Universities (No.2022YJSDC05)+1 种基金the China Scholarship Council (No.202206430058)the Yueqi Scholar Fund of China University of Mining and Technology (Beijing).
文摘Airborne microplastics(MPs)are important pollutants that have been present in the environment for many years and are characterized by their universality,persistence,and potential toxicity.This study investigated the effects of terrestrial and marine transport of MPs in the atmosphere of a coastal city and compared the difference between daytime and nighttime.Laser direct infrared imaging(LDIR)and polarized light microscopy were used to characterize the physical and chemical properties of MPs,including number concentration,chemical types,shape,and size.Backward trajectories were used to distinguish the air masses from marine and terrestrial transport.Twenty chemical types were detected by LDIR,with rubber(16.7%)and phenol-formaldehyde resin(PFR;14.8%)being major components.Three main morphological types of MPs were identified,and fragments(78.1%)are the dominant type.MPs in the atmosphere were concentrated in the small particle size segment(20-50μm).The concentration of MPs in the air mass from marine transport was 14.7 items/m^(3)-lower than that from terrestrial transport(32.0 items/m^(3)).The number concentration of airborne MPs was negatively correlated with relative humidity.MPs from terrestrial transport were mainly rubber(20.2%),while those from marine transport were mainly PFR(18%).MPs in the marine transport air mass were more aged and had a lower number concentration than those in the terrestrial transport air mass.The number concentration of airborne MPs is higher during the day than at night.These findings could contribute to the development of targeted control measures and methods to reduce MP pollution.
基金supported by the Natural Science Foundation of Hebei Province(Nos.B2022407001 and D2021501004)the National Natural Science Foundation of China(No.42075107)the Fundamental Research Funds for the Central Universities(No.N2223011).
文摘An intense Asian dust storm invadedQinhuangdao,a coastal city ofNorth China on April 11-14,2023.We analyzed the bulk water-soluble inorganic ions(WSII)of PM_(10)and PM_(2.5)using an Ion Chromatograph and investigated individual particlemorphology and elemental composition using a scanning electron microscope coupled with energy dispersive X-ray.The results showed when the dust was directly transported to the sampling site from northwestern China(direct transport stages),the PM_(10)mass concentrations were high(675.0μg/m^(3))but the relative humidity(RH)was low.Total WSII were 19.54μg/m^(3)and 11.17μg/m^(3),accounting for 2.90%and 7.25%of the PM_(10)and PM_(2.5),respectively.In addition,the proportion of S-containing individual mineral dust was low(28.7%-35.3%).The results suggested there were limited secondary inorganic aerosol formation.However,when the dust was transported back to the sampling site across the Bohai Sea in the following days(reverse transport stages),both the PM_(10)mass concentrations(462.3μg/m^(3))and RH were high.Total WSII were 43.75μg/m^(3)and 18.71μg/m^(3),accounting for 9.62%and 14.45%of the total PM_(10)and PM_(2.5),respectively.The proportion of S-containing particles was 51.5%-72.5%.In addition,the concentration of NO_(3)^(−)was much higher than that of SO_(4)^(2−).The results suggested both the sulfate and nitrate formation occurred on coarse mineral dust but the nitrate formation exceeded sulfate formation.Interestingly,mostmineral dust,including Sirich particles contained Cl when they passed through the marine atmosphere.The results highlighted the heterogeneous reactions of dust varied in different transport stages.
基金This research was supported by the Project for the Survey of Land and Resources in China(1212010633901)National Natural Science Foundation of China(Grant No.41572090)。
文摘There are 9 major coal-accumulating periods during geological history in China,including the Early Carboniferous,Late Carboniferous-Early Permian,Middle Permian,Late Permian,Late Triassic,Early-Middle Jurassic,Early Cretaceous,Paleogene and Neogene.The coal formed in these periods were developed in different coal-accumulating areas(CAA)including the North China,South China,Northwest China,Northeast China,the Qinghai–Tibet area,and China offshore area.In this paper,we investigated depositional environments,sequence stratigraphy,lithofacies paleogeography and coal accumulation pattern of five major coal-accumulating periods including the Late Carboniferous to Middle Permian of the North China CAA,the Late Permian of the South China CAA,the Late Triassic of the South China CAA,the Early-Middle Jurassic of the North and Northwest China CAA,and the Early Cretaceous in the Northeast China CAA.According to distribution of the coal-bearing strata and the regional tectonic outlines,we have identified distribution range of the coal-forming basins,sedimentary facies types and coal-accumulating models.The sequence stratigraphic frameworks of the major coal-accumulating periods were established based on recognition of a variety of sequence boundaries.The distribution of thick coals and migration patterns of the coal-accumulating centers in the sequence stratigraphic framework were analyzed.The lithofacies paleogeography maps based on third-order sequences were reconstructed and the distribution of coal accumulation centers and coal-rich belts were predicted.
基金supported by the National Basic Research Program (973) of China (No.2006CB403701)the Macao Foundation for Development of Science and Technology (No.023/2006/A)+3 种基金the State Key Laboratory of Coal Resources and Safe Mining (China University of Mining and Technology) (No.SKLCRSM09KFB04)the China Postdoctoral Science Foundation Funded Project(No.20090461213)the Shandong Postdoctoral Science Innovation Foundation (No.200902016)the Independent Innovation Foundation of Shandong University
文摘Aerosol samples were collected in summer in Macao, a coastal city of the Pearl River Delta Region in China. Morphology, size, elemental composition, and mixing state of individual aerosol particles were determined by scanning electron microscopy coupled energy dispersive X-ray （SEM/EDX） and transmission electron microscopy （TEM）. Based on the morphologies of 5711 aerosol particles, they consist of soot （32%）, mineral （17%）, secondary-（22%）, and unknown fine particles （29%）. The sizes of these particles were mostly distributed between 0.1 and 0.4 μm. Compositions of 202 mineral particles were obtained by SEM/EDX. Mineral particles were mainly classified into three types： Si-rich, Ca-rich, and Na-rich. The compositions of typical mineral particles can indicate their sources in sampling location. For example, mineral particles, collected along the main street, were associated with trace amounts of heavy metals, such as Zn, Ti, Mn, Ba, Pb, and As. TEM observations indicate that most Na-rich particles were aged sea salt particles （e.g., Na2SO4 and NaNO3） which formed through heterogeneous chemical reactions between sea salt and acidic gases. Additionally, aging time of soot was short in Macao due to high humidity, high temperature, and high levels of sunlight in Macao. Most of soot and fine mineral dust particles were internally mixed with secondary particles.
基金the National Natural Science Foundation of China (Nos. 41472131, 41772161)New Century Excellent Talents Fund of Chinese Ministry of Education (No. 2013102050020)
文摘As one of the most important source rocks and reservoirs of unconventional natural gas, the sedimentary environment and mode of peat swamp（the predecessor of coal seam） is important to the coal seam＇s spatial distribution, material composition, hydrocarbon generation potential, reservoir physical properties, etc. To reveal the depositional characteristics and history of environmental change in a terrestrial basin during a period of peat accumulation, the Middle Jurassic aged #7 coal from Gaoquan in the Qaidam Basin（NW China） was investigated using sedimentology, maceral composition, geochemistry and sequence stratigraphy. Based on identification of the sedimentary shoreline break belt, wave energy depletion point and position of wave base, the peat swamp system can be subdivided into（1） lakeside plain,（2） low energy lakeshore,（3） high energy lakeshore, and（4） shallow lake subfacies. A new method for determining coal facies is proposed based on the combination of environmental parameters including oxidation-reduction levels, energy conditions and the influence of terrigneous sediments. The evolution of the coal seam shows that peat was deposited mainly in the low energy lakeshore and lakeside plain subfacies. Five types of sequence stratigrpahic surface and two types of parasequence were identified. Forced lake regressions and normal lake regressions are attributed as the causes of sequence boundaries. The sequence stratigraphic framework comprises six sequences and corresponding system tracts, and the curve of base-level for each demonstrates a characteristic initial period of slow rising followed by fast rising and then returning to slow rising. A model indicating the relationship among base-level changes, coal facies evolution, and the environmental features in the swamp is proposed that shows the environmental features of the swamp were controlled by both base-level changes and coal facies. Accompanying depositional environment changes from a lakeside plain to lakeshore and shallow lake caused by increasing rate of base-level rise, water paleosalinity, acidity and the percentage of woody plants decrease, and the bog type alters from the low marsh to raised bog.
基金supported by the Projects of International Cooperation and Exchanges of National Science Foundation of China (No.41571130031)the National Basic Research Program of China (No.2013CB228503)partly supported by a Grant-in-Aid for Scientific Research (B) (No.16H02942) from the JSPS
文摘Traffic vehicles, many of which are powered by port fuel injection(PFI) engines, are major sources of particulate matter in the urban atmosphere. We studied particles from the emission of a commercial PFI-engine vehicle when it was running under the states of cold start, hot start, hot stabilized running, idle and acceleration, using a transmission electron microscope and an energy-dispersive X-ray detector. Results showed that the particles were mainly composed of organic, soot, and Ca-rich particles, with a small amount of S-rich and metal-containing particles, and displayed a unimodal size distribution with the peak at 600 nm. The emissions were highest under the cold start running state, followed by the hot start, hot stabilized, acceleration, and idle running states. Organic particles under the hot start and hot stabilized running states were higher than those of other running states. Soot particles were highest under the cold start running state. Under the idle running state, the relative number fraction of Ca-rich particles was high although their absolute number was low. These results indicate that PFI-engine vehicles emit substantial primary particles,which favor the formation of secondary aerosols via providing reaction sites and reaction catalysts, as well as supplying soot, organic, mineral and metal particles in the size range of the accumulation mode. In addition, the contents of Ca, P, and Zn in organic particles may serve as fingerprints for source apportionment of particles from PFI-engine vehicles.
基金supported by the National Science and Technology Major Project(No.2016ZX05041004-003)the China Geological Survey Scientific Research Project(No.DD20160204)+1 种基金the Guiding Program of Liaoning Natural Science Founds(No.2019-ZD-0046)the Scientific Research Funding Project of Liaoning Education Department(No.LJ2019JL004)。
文摘Coal correlation cannot only guide coal and coalbed methane exploitation,but may also provide valuable information for the evolution of the paleoclimate and paleoenvironment during coalaccumulation periods.It is difficult to undertake coal correlation in a terrestrial basin due to multiple superimposed coal seams and a lack of effective marker beds.In this study,based on the analyses of coal-bearing sedimentary environments and the observations of field outcrops and drilling cores,three key sequence surfaces of the Middle Jurassic Xishanyao Formation were identified in the middle part of the southern Junggar Basin.Three third-order sequences(S.Ⅲ1,S.Ⅲ2 and S.Ⅲ3)and ten fourth-order sequences were divided within the Xishanyao Formation.Regional coal correlation was finally identified,combined with the layered vertical pattern coal and its interval thickness,coal maceral,and coal quality data.In terms of the coal correlation within a specific sequence set,the interval of the B2–B3 coals was approximately three times thicker than that of the B3–B5 coals,which was the main marker for regional coal correlation in the Lower Xishanyao Formation.Furthermore,the phenomena of steadily developed B4 coal seam(2–3 m in thickness)across the Liuhuanggou coal mining area(eastern study region)and the large-small-large variation for intervals between the B8 and B9,B9 and B10,and B10 and B11 coal seams in the Manasi coal mining(western study region)were also an effective means for local coal correlation.Increasing vitrinite and sulphur content and decreasing inertinite content in a third-order sequence were found,which were likely to be closely related to lake level fluctuations.Based on the variation of coal macerals,the wildfire frequency gradually decreased from the bottom to the top of the Xishanyao Formation.The predicted O2level of the S.Ⅲ1,S.Ⅲ2,and S.Ⅲ3 of the Xishanyao Formation was 26.36%,24.22%,and 22.51%,respectively.Except for global paleoclimate effects,the provenance direction changes caused by the Bogda Mountains uplifts would result in a regular variation of coal maceral and coal quality across the study region.
基金supported by the National Natural Science Foundation of China(NSFC)(Grant Nos.42075107 and 41572090)the Yueqi Scholar fund of China University of Mining and Technology(Beijing)。
文摘Epidemiological studies have suggested that inhalation exposure to indoor ambient air from coal-burning environments is causally associated with respiratory health risks.In order to explore the toxicological mechanisms behind the adverse health effects,the hemolytic activity of PM_(10)(particulate matter with an aerodynamic diameter of 10 um or less)samples collected from homes burning coal in the recognized China"cancer village"Xuanwei were evaluated and matched against their trace elemental contents.The results demonstrated that the hemolytic activity of indoor PM_(10) in coal-burning environments ranged from 4.28%to 5.24%,with a clear positive dose-response relationship.Although low dose samples exhibited a reduced hemolytic activity,PM_(10) could have a toxic effect upon people in a coal-burning indoor environment for extended time periods.The concentrations of analyzed trace elements in PM_(10) samples ranged from 6966 to 12,958 ppm.Among the analyzed elements,Zn,Ti,Ni,Cu,Pb,Ba,Mn,Cr and V were found at higher concentrations and accounted for over 95%of the total elements.The concentrations of total analyzed elements in the PM_(10) samples revealed a significant positive correlation with PM_(10) hemolytic activity.Of the analyzed elements,Zn,Pb and Cs positively correlated with hemolysis,while Li,U and V negatively correlated with the hemolysis of human red blood cells(RBCs).Therefore,the heavy metal elements could be one of the main factors responsible for the hemolytic capacity of indoor PM_(10) in coal-burning environments.
基金supported by the National Basic Research Program of China (973 Program) (No. 2013CB228503)the Projects of International Cooperation and Exchanges NSFC (No. 41571130031)
文摘Coal combustion in the domestic stoves, which is common in most parts of the Chinese countryside, can release harmful substances into the air and cause health issues. In this study, particles emitted from laboratory stove combustion of the raw powder coals were analyzed for morphologies and chemical compositions by using transmission electron microscopy （TEM） coupled with energy-dispersive X-ray spectrometry （EDX）. The coal burning-derived individual particles were classified into two groups： carbonaceous particles （including soot aggregates and organic particles） and non-carbonaceous particles （including sulfate, mineral and metal particles）. The non-carbonaceous particles, which constituted a majority of the coal burning-derived emissions, were subdivided into Si-rich, S-rich, K-rich, Ca-rich, and Fe-rich particles according to the elemental compositions. The Si-rich, S-rich and K-rich particles are commonly observed in the coal burning emission. The proportions for particles of different types exhibit obvious coal-issue dependence. Burning of coal with high ash yield could emit more non-carbonaceous particles, and burning of coal with high sulfur content can emit more S-rich particles. By comparing the S-rich particles from this coal burning experiment with those in the atmosphere, we draw a conclusion that some S-rich particles in the atmosphere in China could be mainly sourced from coal combustion.
基金supported by the National Natural Science Foundation of China(NSFC)(Grant No.42075107)the Projects of International Cooperation and Exchanges NSFC(Grant No.41571130031)the Yueqi Scholar fund of China University of Mining and Technology(Beijing).
文摘Corona Virus Disease 2019(COVID-19)caused by the novel coronavirus,results in an acute respiratory condition coronavirus 2(SARS-CoV-2)and is highly infectious.The recent spread of this virus has caused a global pandemic.Currently,the transmission routes of SARS-CoV-2 are being established,especially the role of environmental transmission.Here we review the environmental transmission routes and persistence of SARS-CoV-2.Recent studies have established that the transmission of this virus may occur,amongst others,in the air,water,soil,cold-chain,biota,and surface contact.It has also been found that the survival potential of the SARS-CoV-2 virus is dependent on different environmental conditions and pollution.Potentially important pathways include aerosol and fecal matter.Particulate matter may also be a carrier for SARS-CoV-2.Since microscopic particles can be easily absorbed by humans,more attention must be focused on the dissemination of these particles.These considerations are required to evolve a theoretical platform for epidemic control and to minimize the global threat from future epidemics.
基金supported by the"Strategic Priority Research Program-Formation Mechanism and Control Strategies of Haze in China"of the Chinese Academy of Sciences(No.XDB05010100),the National Basic Research Program(973)of China(No.2013CB228503,2010CB732304)
文摘The frequent haze days around the Chinese capital of Beijing in recent years have aroused great attention owing to the detrimental effects on visibility and public health. To discover the potential health effects of the haze, oxidative capacities of airborne particles collected in Beijing during haze and clear days were comparably assessed by a plasmid scission assay. Eleven water-soluble trace elements （As, Cd, Cr, Cu, Mn, Ni, Pb, V, Se, T1, and Zn） in the size-segregated airborne particles were quantitatively analyzed by inductively coupled plasma mass spectrometry, and most of the water- soluble trace elements were found to mainly concentrate in the fine particle size of 0.56-1.0 μm. In comparison with clear days, the mass concentrations of 11 analyzed water-soluble trace elements remarkably increased during haze days, and the oxidative capacities determined by the plasmid scission assay were markedly elevated accordingly during the haze days under the same dosage of particles as for those during clear days. Water-soluble trace elements in airborne particles, such as Cu, V, and particularly Zn, were found to have significantly positive correlations with the plasmid DNA damage rates. Because Cu, V, and Zn have been considered as bioavailable elements, the evident increase of these elements during haze days may be greatly harmful to human health.
基金This research is supported by the National Science and Technology Major Project(2016ZX05041004-003)the National Natural Science Foundation of China(41572090)+1 种基金Fundamental Research Funds for Central Universities of China University of Mining and Technology(Beijing)Yue Qi Scholar Project of China University of Mining and Technology(Beijing).
文摘The Early Cretaceous is an important coal accumulation period in China.Abundant coal resources were formed in the southeastern margin of Songliao Basin.Sequence stratigraphy and coal accumulation of the Early Cretaceous in the southeastern margin of Songliao Basin have been studied on the basis of extensive outcrop and borehole data.Based on regional unconformity,basal erosional surfaces of incised valley fills,and abrupt depositional facies-reversal surface,six sequence boundaries have been identified,which subdivide the Early Cretaceous coal-bearing series into 5 third-order sequences.Sequence I corresponds to Huoshiling Formation,sequences II and III correspond to member I and member II of Shahezi Formation.Sequences IV and V correspond to member I and member II of Yingcheng Formation.Sequence I developed at the initial subsiding stage,sequence II and III developed during the stable subsiding stage,while sequence IV and V developed during the basin shrinkage stage.The major coal seams were developed in the sequence II and III,which ensured the relative balance between the increase rate of the accommodation space and the rate of peat accumulation for a longer period,thus forming a thick coal seam.
文摘A severe Asian Dust Storm(ADS)event occurred on April 16-17th,2006 in northem China.Mineral components of dust samples were analyzed using X-ray diffraction(XRD).The result indicates that dust particles were dominated by quartz(37.4%)and clay(32.9%),followed by plagioclase(13.7%),with small amounts of calcite,K-feldspar,dolomite,homblende,and gypsum(all【10%).
基金supported by the Projects of International Cooperation and Exchanges NSFC(No.41571130031)the National Basic Research Program of China(No.2013CB228503)the Yueqi Scholar Fund of China University of Mining and Technology(Beijing)。
文摘Emission from burning coals is one of the major sources of the airborne particles in China.We carried out a study on the rare earth elements(REEs)in the inhalable particulate matter(PM10)emitted from burning coals and soil-coal honeycomb briquettes with different volatile contents and ash yields in a combustion-dilution system.Gravimetric analysis indicates that the equivalent mass concentration of the PM10 emitted from burning the coals is higher than that emitted from burning the briquettes.The ICP-MS analysis indicates that the contents of total REEs in the coal-burning PM10 are lower than those in the briquetteburning PM10.In addition,the contents of the light rare earth elements(LREEs)are higher than those of the heavy rare earth elements(HREEs)in the PM10 emitted from burning the coals and briquettes,demonstrating that the REEs in both the coal-burning and briquetteburning PM10 are dominated by LREEs.The higher contents of total REEs and LREEs in the coal-burning PM10 are associated with the higher ash yields and lower volatile contents in the raw coals.A comparative analysis indicates that the La/Sm ratios in the PM10 emitted from burning the coals and briquettes,being lower than 2,are lower than those in the particles from gasoline-powered vehicle emission.
文摘Previous studies of coal sequence stratigraphy have concentrated on coals associated with paralic depositional systems.Little attention has been paid to their counterparts in non-marine intra-mountain coal basins.The northern Qaidam Basin of northwestern China has been extensively developed with abundant oil and gas as well as coal resources in its Jurassic non-marine successions.
文摘This paper analyses the sequence stratigraphy and palaeogeography of the Early and early Middle Jurassic coal measures in the Turpan-Hami Basin,northwestern China.The controls of the palaeogeography and sequence stratigraphy on the coal accumulation in this basin have been discussed.The results show that the coal measures were formed in a fluvial-delta-lacustrine sedimentary system,and a total of 4 third-order sequences were developed.
文摘The Qinshui Basin in southeastern Shanxi Province is an important base for coalbed methane exploration and production in China.The methane reservoirs in this area are the Carboniferous and Permian coals and their thickness are strongly controlled by the depositional environments and the sequence stratigraphic framework.This paper analyzes the high-resolution sequence stratigraphy of the Permo-Carbo-niferous Taiyuan and Shanxi Formations.
文摘The northern type Longtan Formation of the Late Permian in central Hunan is dominated by an assemblage of greyish black mudstone,siltstone,sandy mudstone,fine sandstone and coals,and contains a variety of sedimentary structures such as thin sandstone-mudstone interbedded bedding,flaser beddings,lenticular beddings.
文摘Based on analyses of the lithofacies palaeo-geography of the Taiyuan and the Shanxi Formations in the Qinshui Basin, the spatial variations of the coal seam thickness, coal maceral composition, coal quality, and gas content, together with the lithofacies of the surrounding rocks in each palaeogeographic unit were investigated. The results show that the thick coals of the Taiyuan Formation are mainly distributed in delta and barrier island depositional units in the Yangquan area in the northern part of the basin and the Zhangzi area in the southeastern part of the basin. The thick coals of the Shanxi Formation are located within transitional areas between delta plain and delta front depositional units in the central southern part of the basin. The Taiyuan Formation generally includes mudstone in its lower part, thick, continuous coal seams and limestones in its middle part, and thin, discontinuous coal seams and limestone and sand-mud interbeds in its top part. The Shanxi Formation consists of thick, continuous sandstones in its lower part, thick coal seams in its middle part, and thin coal seams, sandstone, and thick mudstone in its upper part. From the perspective of coal-bearing sedimentology and coalbed methane (CBM) geology, the lithology and thickness of the surrounding rocks of coal seams play more significant roles in controlling gas content variation than other factors such as coal thickness, coal macerals, and coal quality. Furthermore, it is found that the key factors influencing the gas content variation are the thicknesses of mudstone and limestone overlying a coal seam. At similar burial depths, the gas content of the Taiyuan coal seams decreases gradually in the lower delta plain, barrier-lagoon,delta front, barrier-tidal flat, and carbonate platform depositional units. The CBM enrichment areas tend to be located in zones of poorly developed limestone and well-developed mudstone. In addition, the gas content of the Shanxi Formation is higher in the coals of the delta front facies compared to those in the lower delta plain. The CBM enrichment areas tend to be associated with the thicker mudstones. Therefore, based on the lithologic distribution and thickness of the rocks overlying the coal seam in each palaeogeographic unit of the Taiyuan and Shanxi Formations, the areas with higher gas content are located in the north-central basin for the Taiyuan coals and in the southern basin for the Shanxi coals. Both of these areas should be favorable for CBM exploration in the Qinshui Basin.
