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Identification of secondary organic aerosols based on aerosol mass spectrometry

中国科学：化学英文版 2010年第12期53卷 2593-2599页

作者： HUANG XiaoFeng 1,ZHAO QianBiao 1,2,HE LingYan 1,HU Min 2,BIAN QiJing 3,XUE Lian 1 & ZHANG YuanHang 2 1 Key Laboratory for Urban Habitat environmental science and technology School of environment and Energy,peking university Shenzhen Graduate School,Shenzhen 518055,china 2 State Key Joint Laboratory of environmental Simulation and Pollution Control college of environmental sciences and engineering,peking university,beijing 100871,china 3 division of environment,hong kong university of science & technology,hong kong,china 1. Key Laboratory for Urban Habitat environmental science and technology School of environment and Energy Peking University Shenzhen Graduate School Shenzhen 518055 China2. State Key Joint Laboratory of Environmental Simulation and Pollution Control college of environmental sciences and engineering Peking University Beijing 100871 China3. Division of Environment Hong Kong University of Science & Technology Hong Kong China

Secondary organic aerosol (SOA) is one of the major components of aerosols in the atmosphere and has not been well understood so *** to the complex chemical composition of organic aerosols,the identification of SOA has been a hotspot and difficult issue in the field of aerosol *** study attempts to quantitatively identify SOA in winter of Shenzhen based on positive matrix factorization (PMF) *** sources were resolved and SOA was identified subsequently according to the characteristic ion fragments measured by highly time-resolved aerosol mass spectrometer *** showed that in the winter of Shenzhen the average SOA concentration was 9.41±6.33 g/m 3,accounting for 39.9±21.8% of the total organic *** with primary organic aerosol (POA),the SOA concentrations had no large variation,suggestive of characteristics of regional secondary *** ratio of SOA/BC had pronounced diurnal variation,similar to that of O x (O3+NO2),indicating SOA formation was significantly controlled by activity of photochemistry in the *** most effective period for SOA formation was from 9 am～3 pm since the SOA/BC ratio increased by 122% during this *** study provides a new technical method and a new idea for SOA investigation.

关键词： secondary organic aerosol aerosol mass spectrometry positive matrix factorization (PMF)

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Research progress and prospect of low-carbon biological technology for nitrate removal in wastewater treatment

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Frontiers of environmental science & engineering 2024年第7期18卷 1-21页

作者： Ru Zheng Kuo Zhang Lingrui kong Sitong Liu college of environmental sciences and engineering Peking UniversityBeijing 100871China Key Laboratory of Water and Sediment sciences Ministry of Education of ChinaBeijing 100871China Eco-environment and Resource Efficiency Research Laboratory School of Environment and EnergyPeking University Shenzhen Graduate SchoolShenzhen 518055China

Wastewater treatment plants are the major energy consumers and significant sources of greenhouse gas emissions,among which biological nitrogen removal of wastewater is an important contributor to carbon ***,traditional heterotrophic denitrification still has the problems of excessive residual sludge and the requirement of external carbon ***,the development of innovative low-carbon nitrate removal technologies is *** review outlines the key roles of sulfur autotrophic denitrification and hydrogen autotrophic denitrification in low-carbon wastewater *** discovered nitrate/nitrite dependent anaerobic methane oxidation enables sustainable methane emission reduction and nitrogen removal by utilizing available methane in *** microorganisms exhibited a promising potential to achieve carbon-negative nitrate ***,the algal-bacterial symbiosis system and photogranules offer effective and prospective low-carbon options for nitrogen ***,the emerging nitrate removal technology of photoelectrotrophic denitrification and the underlying,photoelectron transfer mechanisms are ***,we summarize and prospect these technologies,highlighting that solar-driven biological nitrogen removal technology is a promising area for future sustainable wastewater *** review has important guiding significance for the design of low-carbon wastewater treatment systems.

关键词： Carbon emissions Low-carbon Biological nitrogen removal Denitrification

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Effects of genistein, daidzein and glycitein on the osteogenic and adipogenic differentiation of bone marrow stromal cells and on the adipogenic trans-differentiation of osteoblasts

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Progress in Natural science:Materials International 2005年第11期15卷 993-999页

作者： LI Xianghui, ZHANG Jinchao, SUI Senfang and YANG Mengsu (State Key Laboratory of Biomembrane, Department of Biological sciences and Biotechnology, Tsinghua university, beijing 100084, china Department of Chemistry, college of Chemistry & environmental science, Hebei university, Baoding 071002, china Department of Biology and Chemistry, City university of hong kong, hong kong, china) State Key Laboratory of Biomembrane Department of Biological Sciences and Biotechnology Tsinghua University Beijing 100084 China. Department of Chemistry College of Chemistry & Environmental Science Hebei University Baoding 071002 China. Department of Biology and Chemistry City University of Hong Kong Hong Kong China

The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT), alkaline phosphatase (ALP) activity and oil red O assays were used to examine the effects of genistein, daidzein and glycitein on the osteogenic and adipogenic differentiation of primary mouse bone marrow stromal cells (MSCs) and the adipogenic trans-differentiation of primary mouse osteoblasts. The results indicated that daidzein, genistein and glycitein at concentrations from 1×10-8 mol/L to 1×10-5mol/L promoted the proliferation of MSCs and osteoblasts; genistein, daidzein and glycitein promoted osteogenic differentiation and inhibited adipogenic differentiation of MSCs, and inhibited adipocytic transdifferentiation of osteoblasts at appropriate concentrations as 17β-estradiol. It suggests that genistein, daidzein and glycitein regulate a dual differentiational process of MSCs into the osteogenic and adipogenic lineages, and trans-differentiational process of primary osteoblasts into the adipocyte lineages, causing a lineage shift toward osteoblast. Protective effects of them on bone may be mediated by a reversal of adipogenesis which may promote the proliferation, differentiation and mineralization of osteoblasts, and make adipocytes secrete less cytokines which may promote osteoclast formation and activation. In addition, the results also indicated that genistein, daidzein and glycitein may be helpful in preventing the development of steroid induced osteonecrosis.

关键词： genistein daidzein glycitein bone marrow stromal cells osteoblasts osteogenic differentiation adipogenic differentiation adipogenic trans-differentiation.

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The impact of vegetation restoration on erosion-induced sediment yield in the middle Yellow River and management prospect

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science china Earth sciences 2005年第6期48卷 724-741页

作者： CHEN Hao1, ZHOU Jinxing2, CAI Qiangguo1, YUE Zhongqi3, LU Zhongchen4, LIANG Guanglin1& HUANG Jianguo5 1. Key Laboratory of Water Cycle and Related Land Surface Processes, Institute of Geographic sciences and Natural Resources Re-search, Chinese Academy of sciences, beijing 100101, china 2. Institute of Forestry, Chinese Academy of Forestry sciences, beijing 100091, china 3. Department of Civil engineering, university of hong kong, hong kong, china 4. Eco-environmental Research Center, Chinese Academy of sciences, beijing 100085, china 5. college of Resources and environment, Southwest Agricultural university, Chongqing 400716, china Correspondence should be addressed to Chen Hao 1. Key Laboratory of Water Cycle and Related Land Surface Processes Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences 100101 Beijing China 2. Institute of Forestry Chinese Academy of Forestry Sciences 100091 Beijing China 3. Department of Civil engineering University of Hong Kong Hong Kong China 4. Eco-environmental Research Center Chinese Academy of Sciences 100085 Beijing China 5. college of Resources and environment Southwest Agricultural University 400716 Chongqing China

According to the characteristics of water and erosion environments of different natural zones on the Loess Plateau, this paper studies changes of vegetation types, distribution boundaries of forest and grass as well as restoration capacity of vegetation in different natural zones in the middle Yellow River. The annual precipitation of 530 mm is the critical annual pre-cipitation for forest and grass distribution in the middle Yellow River. Among the zonal and azonal environmental factors affecting watershed sediment yield, the intermediate diameter D50 (mm) of suspended load and forest coverage (V, %) play the leading role. Of them the effect weight of forest coverage (V, %) on catchments sediment yield is only 3.4% less than the role of the intermediate diameter (D50, mm), they are almost the same. To effectively control soil erosion in semiarid, especially in hilly-gullied areas and make sediment transport modulus reduce to less than 6000 t/km2, it is rather difficult by merely relying on natural restoration of forest. In the process of cultivated land conversion into forest land and grassland, measures suiting local conditions should be adopted in tree species selection and artificial afforestation (grass planting) based on management with biological measures for slopeland and engineering measures for hilly-gullied areas, so that watershed forest coverage in key counties can reach at least over 30%.Compared with the standard period of precipitation prior to the 1960s, with the decrease of an-nual precipitation at various periods, plant productivities decline to different degrees under natural conditions. The main reason accountable for the low survival rate of new seedlings and grass over years is due to precipitation decrease. In light with regression models of annual pre-cipitation and natural vegetation productivities, it is possible to obtain estimated values of wa-tershed natural vegetation productivity and eco-water consumption needed for the restoration to

关键词： vegetation restoration, eco-water requirement, watershed sediment yield, the middle Yellow River.

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Unveiling the mechanisms of Fe(Ⅲ)-loaded chitosan composite(CTS-Fe)in enhancing anaerobic digestion of waste activated sludge

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Journal of environmental sciences 2024年第4期138卷 200-211页

作者： Boaiqi Zhang Ziwen Zhao RuiMa Nan Chen Zhe kong Zhongfang Lei Zhenya Zhang Graduate School of Life and environmental sciences University of Tsukuba1-1-1 TennodaiTsukubaIbaraki 305-8572Japan The Key Laboratory of Water and Sediment sciences Ministry of Education/State Environmental Protection Key Laboratory of All Material Fluxes in River Ecosystems/College of Environmental Sciences and EngineeringPeking UniversityBeijing 100871China South china Institute of environmental sciences Ministry of Ecology and EnvironmentGuangzhou 510345China School of Water Resources and environment China University of Geosciences(Beijing)Beijing 100083China School of environmental science and engineering Suzhou University of Science and TechnologySuzhou 215009China

Anaerobic digestion(AD)of waste activated sludge(WAS)is usually limited by the low generation efficiency of ***(Ⅲ)-loaded chitosan composite(CTS-Fe)have been reported to effectively enhanced the digestion of WAS,but its role in promoting anaerobic sludge digestion remains *** present study,the effects of CTS-Fe on the hydrolysis and methanogenesis stages of WAS anaerobic digestion were *** addition of CTSFe increased methane production potential by 8%-23%under the tested conditions with the addition of 5-20 g/L ***,the results demonstrate that the addition of CTS-Fe could effectively promote the hydrolysis of WAS,evidenced by lower protein or polysaccharides concentration,higher soluble organic carbon in rector adding CTS-Fe,as well as the increased activity of extracellular hydrolase with higher CTS-Fe ***,the enrichment of Clostridia abundance(iron-reducing bacteria(IRBs))was observed in CTS-Fe adding reactor(8.9%-13.8%),which was higher than that in the control reactor(7.9%).The observation further suggesting the acceleration of hydrolysis through dissimilatory iron reduction(DIR)process,thus providing abundant substrates for ***,the presence of CTS-Fe was inhibited the acetoclastic and hydrogenotrophic methanogenesis process,which could be ascribed to the Fe(Ⅲ)act as electron acceptor coupled to methane for anaerobic ***,coenzyme F420 activity in the CTS-Fe added reactor was 34.9% lower than in the blank,also abundance of microorganisms involved in hydrogenotrophic methanogenesis was *** from this study could provide theoretical support for the practical applications of CTS-Fe.

关键词： Chitosan-Fe(Ⅲ)composite Methanogenesis Dissimilatory iron reduction Enzyme activity Microbial community structure

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Analysis of china’s PM_(2.5)and ozone coordinated control strategy based on the observation data from 2015 to 2020

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Journal of environmental sciences 2024年第4期138卷 385-394页

作者： Liuwei kong Mengdi Song Xin Li Ying Liu Sihua Lu Limin Zeng Yuanhang Zhang State Key Joint Laboratory of environmental Simulation and Pollution Control College of Environmental Sciences and EngineeringPeking UniversityBeijing 100871China

The coordinated control of PM_(2.5)and ozone has become the strategic goal of national air pollution *** the gradual decline in PM_(2.5)concentration and the aggravation of ozone pollution,a better understanding of the coordinated control of PM_(2.5)and ozone is urgently ***,we collected and sorted air pollutant data for 337 cities from 2015 to 2020 to explore the characteristics of PM_(2.5)and ozone pollution based on china’s five major air pollution *** results show that it is necessary to continue to strengthen the emission reduction in PM_(2.5)and ozone precursors,and control NO_(x) and VOCs while promoting a dramatic emission reduction in PM_(2.5).The primary method of curbing ozone pollution is to strengthen the emission control of VOCs,with a long-term strategy of achieving substantial emission reductions in NO_(x),because VOCs and NO_(x) are also precursors to PM_(2.5);hence,their reductions also contribute to the reduction in PM_(2.5).Therefore,the implementation of a multipollutant emission reduction control strategy aimed at the prevention and control of PM_(2.5)and ozone pollution is the only means to realize the coordinated control of PM_(2.5)and ozone.

关键词： PM_(2.5) Ozone Coordinated control Multipollutant reduction

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Bacterial Communities in a Buried Ancient Paddy Soil from the Neolithic Age

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Pedosphere 2010年第3期20卷 389-398页

作者： SHEN Wei-Shou YIN Rui LIN Xian-Gui CAO Zhi-hong State Key Laboratory of Soil and Sustainable Agriculture Institute of Soil Science Chinese Academy of SciencesNanjing 210008 (China) college of Chemistry and environmental science Nanjing Normal University Nanjing 210097 (China) Joint Open Laboratory of Soil and environment Institute of Soil Science Chinese Academy of Sciences and Hong KongBaptist University Nanjing 210008 (China)

An ancient irrigated paddy soil from the Neolithic age was excavated at Chuodunshan Site in the Yangtze River Delta, close to Suzhou, china. The soil organic matter (SOM) content in the prehistoric rice soil is comparable to the average SOM content of present rice soils in this region, but it is about 5 times higher than that in the parent materials. As possible biomarkers to indicate the presence of the prehistoric paddy soil, the bacterial communities were investigated using the techniques of aerobic and anaerobic oligotrophic bacteria enumeration, Biolog analysis, and polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE). The results showed that in the buried soil layers, the prehistoric paddy soil had the largest number of aerobic and anaerobic oligotrophic bacteria, up to 6.12 and 5.86 log cfu g-1 dry soil, respectively. The prehistoric paddy soil displayed better carbon utilization potential and higher functional diversity compared to the parent materials and a prehistoric loess layer. The Shannon index and richness based on DGGE profiles of bacterial 16S rRNA genes were higher in prehistoric paddy soil than those in the prehistoric loess soil. It might be concluded that the prehistoric irrigated rice cultivation accumulated the SOM in plowed soil layer, and thus increased soil bacterial populations, metabolic activity, functional diversity and genetic diversity. Bacterial communities might be considered as the sensitive indicators of the presence of the prehistoric paddy soil in china's Yangtze River Delta.

关键词： biomarker denaturing gradient gel electrophoresis oligotrophic bacteria paleosols prehistoric paddy soil

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Long-term thinning decreases the contribution of heterotrophic respiration to soil respiration in subalpine plantations

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Journal of Forestry Research 2024年第3期35卷 189-204页

作者： Longfei Chen Zhibin He Wenzhi Zhao Xi Zhu Qin Shen Mingdan Song Zhengpeng Li Junqia kong Shuping Yang Yuan Gao Northwest Institute of Eco-environment and Resources Chinese Academy of SciencesLanzhou 730000People's Republic of China State Forestry Administration Key Laboratory of Forest Resources and environmental Management Beijing Forestry UniversityBeijing 100083People's Republic of China Academy of Agriculture and Forestry sciences Qinghai UniversityXining 810000People's Republic of China college of Landscape Architecture Zhejiang A&F UniversityHangzhou 310000People's Republic of China

Interest in the dynamics of soil respiration(R_(S))in subalpine forest ecosystems is increasing due to their high soil carbon density and potential sensitivity to environmental ***,as a principal silvicultural practice,the long-term impacts of thinning on R_(S) and its heterotrophic and autotrophic respiration components(R_(h) and Ra,respectively)in subalpine plantations are poorly understood,espe-cially in winter.A 3-year field observation was carried out with consideration of winter CO_(2) efflux in middle-aged sub-alpine spruce plantations in northwestern china.A trench-ing method was used to explore the long-term impacts of thinning on Rs,Rn and R_(a).Seventeen years after thinning,mean annual Rs,Rn and R_(a) increased,while the contribu-tion of R_(h) to R_(s) decreased with thinning *** significantly decreased winter R,because of the reduction in R_(n) but had no significant effect on *** temperature sensitivity(Q_(10))of R_(h) and R_(a) also increased with thinning intensity,with lower Q_(10) values for R_(h)(2.1-2.6)than for Ra(2.4-2.8).The results revealed the explanatory variables and pathways related to R_(n) and R_(a) *** increased soil moisture and nitrate nitrogen(NO_(3)^(-)-N),and the enhanced nitrogen and water availability promoted R_(h) and R_(a) by improving fine root biomass and microbial *** results highlight the positive roles of NO_(3)^(-)-N in stimulating R_(s) components following long-term ***,applications of nitrogen fertilizer are not recommended while thinning subalpine spruce plantations from the perspective of reducing soil CO_(2) *** increased Q_(10) values of R_(s) components indicate that a large increase in soil CO_(2) emissions would be expected following thinning because of more pronounced climate warming in alpineregions.

关键词： Heterotrophic respiration Autotrophic respiration Long-term thinning impacts Cold seasons Subalpine plantations Temperature sensitivity

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Fate of organophosphate esters from the Northwestern Pacific to the Southern Ocean:Occurrence,distribution,and fugacity model simulation

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Journal of environmental sciences 2024年第3期137卷 347-357页

作者： Tengda Shi Ruijing Li Jie Fu Chao Hou Hui Gao Guanjie Cheng Haibo Zhang Shuaichen Jin Liang kong Guangshui Na college of Marine technology and environment Dalian Ocean UniversityDalian 116023China Laboratory for coastal marine eco-environment process and carbon sink of Hainan province/Yazhou Bay Innovation Institute Hainan Tropical Ocean UniversitySanya 572022China National Marine environmental Monitoring Center Dalian 116023China college of Marine Ecology and environment Shanghai Ocean UniversityShanghai 201306China NCS Testing technology Co. Ltd.Beijing 10081China

Eleven organophosphate esters(OPEs)in the air and seawater were investigated from the northwestern Pacific Ocean to the Southern Ocean during the 2018 Chinese 34th Antarctic Scientific *** concentration of total OPEs ranged from 164.82 to 3501.79 pg/m~3in air and from 4.54 to 70.09 ng/L in *** halogenated OPEs,tri(chloropropyl)phosphate(TCPP)and tri(2-chloroethyl)phosphate(TCEP),were generally more abundant than the non-halogenated OPEs.A levelⅢfugacity model was developed to simulate the transfer and fate of seven OPEs in the air and seawater regions of the central Ross *** model results indicate that OPEs are transferred from the air to the seawater in the central Ross Sea in summer,during which the Ross Sea acts as a final OPE *** and wet deposition dominated the processes involving OPE transfer to *** OPE degradation process was also found to be more pervasive in the atmosphere than in the seawater *** findings highlights the importance of long-range transport of OPEs and their air–seawater interface behavior in the Antarctic.

关键词： Organophosphate esters(OPEs) Long-range transport Fugacity model Antarctic Fate

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Effect of daidzin,genistin,and glycitin on osteogenic and adipogenic differentiation of bone marrow stromal cells and adipocytic transdifferentiation of osteoblasts

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Acta Pharmacologica Sinica 2005年第9期26卷 1081-1086页

作者： Xiang-hui LI~1 Jin-chao ZHANG~(2,3) Sen-fang SUI~(1,4) Meng-su YANG~(3,4)1 State Key Laboratory of Biomembrane Department of Biological sciences and Biotechnology,Tsinghua university,beijing 100084,china 2 Department of Chemistry college of Chemistry and environmental science,Hebei university,Baoding 071002,china 3 Department of Biology and Chemistry,City university of hong kong,hong kong,china StateKeyLaboratoryofBiomembrane DepartmentofBiologicalSciencesandBiotechnologyTsinghuaUniversityBeijing10008

Aim:To examine the effect of daidzin,genistin,and glycitin on the osteogenic andadipogenic differentiation of bone marrow stromal cells（MSC）and the adipogenictransdifferentiation of ***:MTT test,alkaline phosphatase（ALP）activity measurement,Oil Red O stain and measurement were ***:Daidzin,genistin,and glycitin 1×10-8,5×10-7,1×10-6,5×10-6,and 1×10-5mol/L all promoted the proliferation of primary mouse bone MSC and *** 5×10-7mol/L and genistin 1×10-6mol/L promoted the osteogenesis *** 1×10-8,5×10-7,1×10-6,5×10-6,and 1×10-5mol/L and glycitin 1×10-8,1×10-6,and 1×10-5mol/L inhibited the adipogenesis of ***,genistin,and glycitin 1×10-8,5×10-7,1×10-6,5×10-6,and 1×10-5mol/L all inhibited the adipocytictransdifferentiation of ***:Daidzin,genistin,and glycitinmay modulate differentiation of MSC to cause a lineage shift toward the osteo-blast and away from the adipocytes,and could inhibit adipocytic transdifferen-tiation of *** could also be helpful in preventing the developmentof osteonecrosis.

关键词： daidzin genistin glycitin bone marrow stro-real cells osteogenic differentiation adipogenic differentiation osteoblasts adipocytic transdifferentiation

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