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Water-soluble organic matter with various polarities in PM_(2.5) over Xi'an,China:Abundance,functional groups,and light absorption

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Particuology 2024年第1期84卷 281-289页

作者： Xueting Yang Shasha Huang Dan Li Hongmei Xu Yaling Zeng Liu Yang Diwei Wang Ningning Zhang Junji Cao Zhenxing Shen Department of environmental science and Engineering Xi'an Jiaotong UniversityXi'an710049China School of environmental science and Engineering Southern University of Science and TechnologyShenzhen518055China State Key Laboratory of Loess and Quaternary geology Institute of Earth EnvironmentChinese Academy of SciencesXi'an710049China

Humic-like substances(HULIS)are a major component of brown carbon and consequently play a major role in climate *** this study,70 PM_(2.5) samples were collected from Xi'an in winter 2019 and summer *** HULIS(HULIS-n),acidic HULIS(HULIS-a),and high-polarity water-soluble organic compounds(HP-WSOC)were analyzed to determine their carbon concentrations and measure their ultraviolet-visible absorption and infrared *** the three components,HULIS-n had the highest carbon content in both winter(3.29±1.45μg m^(-3))and in summer(1.38±1.10μg m^(-3)).The semi-quantitative results for the functional groups revealed that HP-WSOC was rich in carboxylic acids and had high aromaticity in winter,whereas HULIS-n was rich in carboxylic acids in ***,HULJS-a was richer in nitrate esters and saturated aliphatic hydrocarbons in summer than in *** results for specific ultraviolet absorbance(SUVA)and E_(250)/E_(365) revealed that HULIS had higher molecular weight and aromaticity in winter than in ***-n dominated in the total light absorption of HULIS+HP-WSOC in both winter(73.08%)and summer(48.57%).Overall,the results on the carbon content,optical properties,and functional groups of WSOCs with differing polarity can improve un-derstanding of environmental and climatic effects.

关键词： Humic-like substances(HULIS) Aromaticity Fourier-transform infrared(FTIR) spectroscopy Light absorbance

Mass extinctions, their causes and consequences: an interview with Douglas *** and Shuzhong Shen

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National science Review 2024年第1期11卷 66-70页

作者： Shucheng Xie State Key Laboratory of Biogeology and environmental geology China University of Geosciences at Wuhan

‘Mass extinctions’ have been a hot topic for several decades. What triggers a mass extinction? How does a mass extinction impact the evolution of life? How does our ecosystem recover after a mass extinction? These questions attracted the interest of both scientists and the public *** spoke to two renowned researchers in the field of mass extinctions: Prof. Douglas H. Erwin from the National Museum of Natural History of the USA, and Prof. Shuzhong Shen from Nanjing University, China.

关键词： Stratigraphy

Multiple isotopes reveal the driving mechanism of high NO_(3)^(-) level and key processes of nitrogen cycling in the lower reaches of Yellow River

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Journal of environmental sciences 2024年第4期138卷 597-606页

作者： Qianqian Zhang Huiwei Wang Lu Liu Tianlun Zhai Xueqing Zhang Hebei and China Geological Survey Key Laboratory of Groundwater Remediation Institute of Hydrogeology and Environmental GeologyChinese Academy of Geological SciencesHebei 050061China Geo-environmental Monitoring Institute of Hebei Province Hebei 050011China Hebei Provincial Laboratory of Water environmental science Hebei 050037China Hebei Provincial Academy of Ecological environmental science Hebei 050037China

The continuous increase of nitrate(NO_(3)^(-))level in rivers is a hot issue in the ***,the driving mechanism of high NO_(3)^(-)level in large rivers is still lacking,which has limited the use of river water and increased the cost of water *** this study,multiple isotopes and source resolution models are applied to identify the driving mechanism of high NO_(3)^(-)level and key processes of nitrogen cycling in the lower reaches of the Yellow River(LRYR).The major sources of NO_(3)^(-)were sewage and manure(SAM)in the low-flow season and soil nitrogen(SN)and chemical fertilizer(CF)in the high-flow *** was the most key process of nitrogen cycling in the ***,in the biological removal processes,denitrification may not occur *** temporal variation of contributions of NO_(3)^(-)sources were estimated by a source resolution model in the *** proportional contributions of SAM and CF to NO_(3)^(-)in the low-flow and high-flow season were 32.5%-52.3%,44.2%-46.2%and 36.0%-40.8%,54.9%-56.9%,*** driving mechanisms of high NO_(3)^(-)level were unreasonable sewage discharge,intensity rainfall runoff,nitrification and lack of nitrate removal *** control the NO_(3)^(-)concentration,targeted measures should be implemented to improve the capacity of sewage and wastewater treatment,increase the utilization efficiency of nitrogen fertilizer and construct ecological *** study deepens the understanding of the driving mechanism of high nitrate level and provides a vital reference for nitrogen pollution control in rivers to other area of the world.

关键词： Nitrate Driving mechanism Nitrogen cycle Source apportionment Transformation Yellow River

Characteristics and Genesis of Acid Drainage Contamination from a Rock Tunneling Project Site

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Journal of Earth science 2024年第1期35卷 190-200页

作者： Yanyun Li Zejiao Luo Shihua Qi Hubei Key Laboratory of Yangtze River Basin environmental Aquatic science School of Environmental StudiesChina University of GeosciencesWuhan 430078China State Key Laboratory of Biogeology and environmental geology China University of GeosciencesWuhan 430078China

While acid mine drainage(AMD)issues have become a topic of global concern,few studies have focused on acid drainage problems of non-mining *** conducted field research and a series of laboratory experiments to investigate the characteristics,release processes and formation of acid drainage *** rock samples and adjacent surface water,groundwater,soil and sediment samples were collected at a railway tunnel construction site in central China,and various parameters,such as the p H,mineral ion concentrations,and heavy metal concentrations,were *** on the measured concentrations,surface water and sediments were seriously contaminated by acids,sulfate salts and heavy *** in surface water showed a decreasing tendency as the distance from the spoils increased,while that in sediments showed a greater influence of coprecipitation and adsorption processes of heavy metal *** eluviation experiments of three rock samples indicated that R2(silty fine sandstone)was the most likely major acid drainage *** ferrooxidans was cultured and isolated from contaminated water to study the oxidation conditions during the release *** significant release of acid drainage when air and bacteria were both in the culture container suggested that oxygen and bacteria were necessary to produce acid drainage from spoils.

关键词： acid mine drainage heavy metals leaching oxidation

Superwettable interface towards biodetection in confined space

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Nano Research 2024年第2期17卷 602-617页

作者： Zexu Pang Zhikang Cao Wanlu Li Wenxia Xu Yingying Zhang Qitao Zhou Jing Pan Fan Xia State Key Laboratory of Biogeology and environmental geology Engineering Research Center of Nano-Geomaterials of the Ministry of EducationFaculty of Materials Science and ChemistryChina University of GeosciencesWuhan 430074China

The detection of biomarkers with both high sensitivity and specificity is crucial for the diagnosis and treatment of related ***,many current detections employ ex-situ detection method and non-confined condition,thus have many problems,which may eventually lead to inaccurate detection *** to detection in non-confined space,detection in confined space can better reflect the real in-vivo ***,the construction of detection for target molecules in confined space has great significance for both theoretical research and practical *** realize the detection of target molecules in confined space,the probes should accurately enter the confined space where the target molecules reside and interact with the ***,how to explore and utilize the properties of the interface(for example,bioinspired superwettability)has always been a hot and difficult topic in this ***,the recent advances and our efforts in recent 10 years on detection of bio-target molecules in confined space with superwettable interface have been introduced from the perspective of the detection *** suitable and most widely employed detection methods for target molecules in confined spaces are introduced ***,recent progresses for related detections based on visual,optical,and electrochemical detection methods are presented ***,the perspective for detection in confined space is discussed for the future development of biochemical detection.

关键词： biodetection superwettability confined space interface

Effect of Reclamation on the Groundwater-Lake Water Interaction in Chen Lake

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Journal of Earth science 2024年第3期35卷 1083-1086页

作者： Kun Lei Teng Ma Liuzhu Chen Zhenxing Li Yu Chen School of environmental Studies State Key Laboratory of Biogeology and Environmental GeologyChina University of GeosciencesWuhan 430078China

0 INTRODUCTION To relieve the short supply of suitable land for residing,cultivating,and commerce,it is accepted to reclaim land from lakes,river estuaries,and coastal regions in many countries(Mancini et al.,2020).The large-scale reclamation activities have an irreversible effect on the mico-geomorphology and hydrodynamic system of seasonally flooded areas(Zhang et al.,2019;Yu et al.,2018).For example,coastal regions reclaimed extended the groundwater flow paths,as well as created groundwater level rise,resulting in water-logging in the reclaimed area(Hu et al.,2008).Similar changes in groundwater flow systems may alter groundwater-lake water interactions,and it can ultimately affect the water cycle in the lake ***,such detailed studies are presently *** addition,natural exchanges between the lake and groundwater systems can be strongly affected by physical hydrological processes(Javadzadeh et al.,2020),chemical properties(Kamtchueng et al.,2015),and bioto behavior(Hancock et al.,2005).

关键词： groundwater coastal logging

Bulk geochemistry,Rb-Sr,Sm-Nd,and stable O-H isotope systematics of the Metzimevin high-grade iron ore deposit,Mbalam iron ore district,southern Cameroon

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Acta Geochimica 2024年第4期43卷 677-706页

作者： Samndong Cyril Tufoin Cheo Emmanuel Suh Tabod Charles Tabod George Lemewihbwen Ngiamte Department of geology Mining and Environmental ScienceThe University of BamendaB.P.39BambiliNorth West RegionCameroon Economic geology Unit Department of GeologyUniversity of BueaP.O.63BueaSouth West RegionCameroon Department of Physics Faculty of ScienceThe University of BamendaB.P.39BambiliNorth West RegionCameroon Department of geology Pan-African University Life and Earth Sciences Institute(PAULESI)University of IbadanIbadanNigeria

Bulk geochemistry,Sr,Nd,and O-H isotope systematics are reported for the first time on banded iron formation(BIF)-hosted high-grade iron ore at the northwestern segment of Congo Craton(CC).Located in Mbalam iron ore district,Southern Cameroon,Metzimevin iron ore deposit is a hematite-magnetite BIF system,dominated by SiO_(2)+Fe_(2)O_(3)(97.1 to 99.84 wt%),with low concentrations of clastic elements e.g.,Al_(2)O_(3),TiO_(2),and HFSE,depicting a nearly pure chemical *** REE+Y signature of the iron deposit displays strong positive Eu anomaly,strong negative Ce anomaly,and chondritic to superchondritic Y/Ho ratios,suggestive of formation by mixed seawater-high temperature hydrothermal fluids in oxidising ***^(87)Sr/^(86)Sr ratios of the BIF are higher than the maximum^(87)Sr/^(86)Sr evolution curves for all Archean reservoirs(bulk silicate earth,Archean crust and Archean seawater),indicating involvement of continentally-derived components during BIF formation and ***Ɛ_(Nd)(t)(+2.26 to+3.77)and Nd model age indicate that chemical constituents for the BIF were derived from undifferentiated crustal source,between 3.002 and 2.88 *** variable and diverse O and H isotope data(−1.9‰to 17.3‰and−57‰to 136‰respectively)indicate that the Metzimevin iron ore formed initially from magmatic plumes and later enriched by magmatic-metamorphic-modified meteoric *** balance calculations indicate mineralisation by combined leaching and precipitation,with an average iron enrichment factor of>2.67 and SiO_(2)depletion factor of>*** is associated with an overall volume reduction of 28.27%,reflecting net leaching and volume collapse of the BIF protholith.

关键词： Bulk geochemistry Rb-Sr Sm-Nd Mitzimevin High-grade iron ore

Water-soluble brown carbon in atmospheric aerosols from the resource-dependent cities:Optical properties,chemical compositions and sources

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Journal of environmental sciences 2024年第4期138卷 74-87页

作者： Haoji Wang Yue Su Yangzheng Liu Fei Xie Xingjun Zhou Ruihong Yu Changwei Lü Jiang He School of Ecology and Environment Inner Mongolia UniversityHohhot 010021China Institute of environmental geology Inner Mongolia UniversityHohhot 010021China environmental Monitoring Center of Inner Mongolia Hohhot 010011China

As a vital type of light-absorbing aerosol,brown carbon(BrC)presents inherent associations with atmospheric photochemistry and climate ***,the understanding of the chemical and optical properties of BrC is limited,especially in some resource-dependent cities with long heating periods in northwest *** study showed that the annual average abundances of Water-soluble BrC(WS-BrC)were 9.33±7.42 and 8.69±6.29μg/m^(3)in Baotou and Wuhai and the concentrations,absorption coefficient(Abs_(365)),and mass absorption efficiency(MAE365)of WS-BrC presented significant seasonal patterns,with high values in the heating season and low values in the non-heating season;while showing opposite seasonal trends for the Absorption Angstr?m exponent(AAE_(300-400)).Comparatively,the levels of WS-BrC in developing regions(such as cities in Asia)were higher than those in developed regions(such as cities in Europe and Australia),indicating the significant differences in energy consumption in these *** combining fluorescence excitation-emission matrix(EEM)spectra with the parallel factor(PARAFAC)model,humic-like(C1 and C2)and proteinlike(C3)substances were identified,and accounted for 61.40%±4.66%and 38.6%±3.78%at Baotou,and 60.33%±6.29%and 39.67%±4.17%at Wuhai,*** results of source apportionment suggested that the potential source regions of WS-BrC varied in heating ***-heating seasons and that the properties of WS-BrC significantly depended on primary emissions(e.g.,combustion emissions)and secondary formation.

关键词： Water-soluble brown carbon Atmospheric aerosols Optical properties PARAFAC Source apportionment

Paleoclimatic application of spectral parameters to the eolian red clay of the Jianzha Basin,northeastern margin of the Tibetan Plateau

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science China Earth sciences 2024年第6期67卷 1952-1966页

作者： Chaofeng FU Ju’e TIAN Xinwen XU Yougui SONG Jun ZUO Feng WANG Lin CHEN Pengfei LI Xiaoke QIANG The School of Earth science and Resources Chang’an UniversityXi’an 710054China State Key Laboratory of Loess and Quaternary geology Institute of Earth and EnvironmentCASXi’an 710061China College of Urban and environmental science Northwest UniversityXi’an 710069China CAS Center for Excellence in Quaternary science and Global Change Xi’an 710061China

Reflectance spectroscopy is rapid,inexpensive,and non-destructive and can provide important information about the mineralogy of rocks and *** measured the reflectance spectroscopy of Miocene red clay deposits on the northeastern margin of the Tibetan Plateau,with the aim of developing a rapid methodology for detecting paleoclimatic *** obtained visible/near-infrared(VNIR)and short-wave infrared(SWIR)spectroscopy data from the red clay in the Jianzha Basin,and analyzed their relationship with independent paleoclimatic records,including mineral contents and environmental magnetic *** results show that the VNIR parameters,including D500,D900,R500,and R900(where D and R represent the depth and reflectance of the absorption peaks around 500 and 900 nm,respectively)are temperature-sensitive and correlated with the magnetic susceptibility,frequency-dependent magnetic susceptibility,and the marine δ^(18)O *** results of frequency-domain analysis of the VNIR parameters show that they reflect climate change on orbital *** parameters,such as AS1400,D1400/D1900 and D1900(where AS represents the asymmetry of the absorption peaks around1400 nm),are correlated with the illite and montmorillonite content,and they are sensitive to the weathering *** spectral parameters of the eolian red clay in the Jianzha Basin reflect regional climatic changes caused by the uplift of the Tibetan Plateau at~8.5 Ma and global climatic cooling at~7.2 Ma,and thus they are applicable as both regional and global paleoenvironmental indicators.

关键词： Visible/near-infrared spectroscopy Short-wave infrared spectroscopy Paleoclimatic indicators Red clay Tibetan Plateau