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Characterization and source apportionment of volatile organic compounds in Hong Kong:A 5-year study for three different archetypical sites 被引量:2
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作者 Yuchen Mai Vincent Cheung +5 位作者 Peter K.K.Louie Kenneth Leung Jimmy C.H.Fung Alexis K.H.Lau Donald R.B.lake Dasa Gu 《Journal of Environmental Sciences》 2025年第5期424-440,共17页
Initial success has been achieved in Hong Kong in controlling primary air pollutants,but ambient ozone levels kept increasing during the past three decades.Volatile organic compounds(VOCs)are important for mitigating ... Initial success has been achieved in Hong Kong in controlling primary air pollutants,but ambient ozone levels kept increasing during the past three decades.Volatile organic compounds(VOCs)are important for mitigating ozone pollution as its major precursors.This study analyzed VOC characteristics of roadside,suburban,and rural sites in Hong Kong to investigate their compositions,concentrations,and source contributions.Herewe showthat the TVOC concentrations were 23.05±13.24,12.68±15.36,and 5.16±5.48 ppbv for roadside,suburban,and rural sites between May 2015 to June 2019,respectively.By using Positive Matrix Factorization(PMF)model,six sources were identified at the roadside site over five years:Liquefied petroleum gas(LPG)usage(33%–46%),gasoline evaporation(8%–31%),aged air mass(11%–28%),gasoline exhaust(5%–16%),diesel exhaust(2%–16%)and fuel filling(75–9%).Similarly,six sources were distinguished at the suburban site,including LPG usage(30%–33%),solvent usage(20%–26%),diesel exhaust(14%–26%),gasoline evaporation(8%–16%),aged air mass(4%–11%),and biogenic emissions(2%–5%).At the rural site,four sources were identified,including aged airmass(33%–51%),solvent usage(25%–30%),vehicular emissions(11%–28%),and biogenic emissions(6%–12%).The analysis further revealed that fuel filling and LPG usage were the primary contributors to OFP and OH reactivity at the roadside site,while solvent usage and biogenic emissions accounted for almost half of OFP and OH reactivity at the suburban and rural sites,respectively.These findings highlight the importance of identifying and characterizing VOC sources at different sites to help policymakers develop targeted measures for pollution mitigation in specific areas. 展开更多
关键词 Volatile organic compounds Positive matrix factorization Source apportionment Ozone formation
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Long Story of Long Antennae:Mesozoic Origins of the Subfamily Macrocerinae(Diptera:Keroplatidae)
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作者 Alicja PEŁCZYŃSKA Vladimir BLAGODEROV +1 位作者 Wiesław KRZEMIŃSKI Agnieszka SOSZYŃSKA 《Acta Geologica Sinica(English Edition)》 2025年第5期1225-1248,共24页
The early evolutionary history of the Macrocerinae subfamily(Diptera:Keroplatidae)is poorly understood.However,new material from the Cretaceous,particularly in amber,provides a better understanding of this subject.We ... The early evolutionary history of the Macrocerinae subfamily(Diptera:Keroplatidae)is poorly understood.However,new material from the Cretaceous,particularly in amber,provides a better understanding of this subject.We reassign the oldest known species of Macrocerinae,Hegalari minor Blagoderov&Arillo,2002,from the amber of Álava(~105 Mya),to the genus Macrocera(M.minor comb.nov.).Furthermore,we reassess the systematic position of the problematic genus Burmacrocera Cockerell,1917 from Cenomanian Burmese amber(~99 Mya),providing evidence that it should be classified within this subfamily.Most significantly,we describe five new species from Burmese amber,including a new genus,Electrocera Pełczyńska&Soszyńska,gen.nov.,with two new species(E.prima Pełczyńska&Soszyńska,gen.et sp.nov.and E.payini Pełczyńska&Soszyńska,gen.et.sp.nov.)and three new Macrocera species(M.vonneguti Pełczyńska&Blagoderov,sp.nov.,M.sevciki Pełczyńska&Krzemiński,sp.nov.and M.pawli Pełczyńska,sp.nov.). 展开更多
关键词 new species palaeoentomology Álava amber Burmese amber Cretaceous Sciaroidea
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Connecting volatile organic compounds exposure to osteoporosis risk via oxidative stress based on adverse outcome pathway methodology
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作者 Haolong Zhou Zhangbo Cui +4 位作者 Dongsheng Di Ziwei Chen Xinyue Zhang Danyang Ling Qi Wang 《Journal of Environmental Sciences》 2025年第9期806-817,共12页
Existing evidence has demonstrated the association between exposure to volatile organic compounds(VOCs)and osteoporosis(OP)risk,but the underlying mechanistic framework remains unclear.This study aimed to explore pote... Existing evidence has demonstrated the association between exposure to volatile organic compounds(VOCs)and osteoporosis(OP)risk,but the underlying mechanistic framework remains unclear.This study aimed to explore potential pathways using adverse outcome pathway(AOP)analysis,and evidence this association in middle-to-old-aged American adults using the updated National Health and Nutrition Examination Survey data.Multivariable-adjusted general linear and weighted quantile sum models were employed to analyze associations of VOC metabolites(VOCMs),representing internal VOCs exposure levels,with OP-related phenotypes.An AOP framework based on network analysis was developed by extracting target genes and phenotypes.Among 3555 American adults aged≥40 years(539 OP participants),we found that increasing urinary 3-and 4-methylhippuric acid,N-acetyl-S-(n-propyl)-l-cysteine(BPMA),and N-acetyl-S-(3-hydroxypropyl)-l-cysteine were associated with elevated OP odds with odds ratios(ORs)(95%confidence intervals,95%CIs)being 1.254(1.016 to 1.548),1.182(1.014 to 1.377),and 1.244(1.029 to 1.505),respectively,per standard deviation.Urinary BPMA and N-acetyl-S-(2-cyanoethyl)-l-cysteine were inversely associated with lumbar spine bone mineral density(BMD),while urinary N-acetyl-S-(2-hydroxypropyl)-l-cysteine was positively associated with hip BMD.Additionally,OP odds increased by 46.0%(95%CI:3.9%to 105.1%)per quartile increment in the VOC mixture.AOP analysis identified 53 target genes and 9 target phenotypes,and 5 of 9 target phenotypes were oxidative stress(OS)-related.Literature and the“AOP 482”framework implied the core role of OS in the VOC exposure and prevalent OP association,with the interleukin-6 as themolecular initiating event.Our findings provided a theoretical basis for further investigation. 展开更多
关键词 Volatile organic compound OSTEOPOROSIS Adverse outcome pathway Oxidative stress
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Net effect of air pollution controls on health risk in the Beijing-Tianjin-Hebei region during the 2022 winter Olympics and Paralympics 被引量:2
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作者 Changqing Lin Peter K.K.Louie +7 位作者 Alexis K.H.Lau Jimmy C.H.Fung Zibing Yuan Minghui Tao Xuguo Zhang Md.Shakhaoat Hossain Chengcai Li Xiang Qian Lao 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2024年第1期560-569,共10页
Due to the non-linearity in ozone(O_(3))formation,reducing the emission of nitrogen oxides(NO_(x))may increase O_(3) concentration.Given the counteractive O_(3) response to NO_(x) reduction,overall impact of air pollu... Due to the non-linearity in ozone(O_(3))formation,reducing the emission of nitrogen oxides(NO_(x))may increase O_(3) concentration.Given the counteractive O_(3) response to NO_(x) reduction,overall impact of air pollution controls can be ambiguous when the assessments focus on the changes in pollutant concentrations.In this study,a risk-based method was used to gauge the net effect of air pollution controls on mortality risk in the Beijing–Tianjin–Hebei(BTH)region during the 2022 Winter Olympics and Paralympics(WOP).This mega-event presents a unique opportunity to investigate the efficacy of deep cuts in pollutant emissions.Results show that O_(3) concentrations greatly increased as nitrogen dioxide(NO_(2))concentrations decreased in the BTH.Due to the active photochemical formations,O_(3) became the dominant pollutant that affected human health during the WOP.Despite the substantial O_(3) increases,the health benefits of NO_(2) reductions overwhelmed the adverse health effects of O_(3) increases in most regions of the BTH(at 81 out of 112 stations).After considering the impacts of particulate matter,the integrated health risk of air pollution mixtures declined almost everywhere in the BTH.Our results underscore the great necessity of changing the assessment paradigm of pollution control from using concentration-based methods to using risk-based methods.Together with the carbon neutrality policy,stringent control of NO_(x)emission from combustion sources is a promising way to achieve synergistic control solutions for air pollution and climate change. 展开更多
关键词 OZONE Nitrogen dioxide Health risk Carbon neutrality MEGA-EVENTS
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Wastewater Surveillance Provides Spatiotemporal SARS-CoV-2 Infection Dynamics
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作者 Xiawan Zheng Kathy Leung +14 位作者 Xiaoqing Xu Yu Deng Yulin Zhang Xi Chen Chung In Yau Kenny W.K.Hui Eddie Pak Ho-Kwong Chui Ron Yang Hein Min Tun Gabriel Matthew Leung Joseph Tsz Kei Wu Malik Peiris Leo Lit Man Poon Tong Zhang 《Engineering》 SCIE EI CAS CSCD 2024年第9期70-77,共8页
Wastewater surveillance(WWS)can leverage its wide coverage,population-based sampling,and high monitoring frequency to capture citywide pandemic trends independent of clinical surveillance.Here we conducted a nine mont... Wastewater surveillance(WWS)can leverage its wide coverage,population-based sampling,and high monitoring frequency to capture citywide pandemic trends independent of clinical surveillance.Here we conducted a nine months daily WWS for severe acute respiratory syndrome coronavirus 2(SARSCoV-2)from 12 wastewater treatment plants(WWTPs),covering approximately 80%of the population,to monitor infection dynamics in Hong Kong,China.We found that the SARS-CoV-2 virus concentration in wastewater was correlated with the daily number of reported cases and reached two pandemic peaks three days earlier during the study period.In addition,two different methods were established to estimate the prevalence/incidence rates from wastewater measurements.The estimated results from wastewater were consistent with findings from two independent citywide clinical surveillance programmes(rapid antigen test(RAT)surveillance and serology surveillance),but higher than the cases number reported by the Centre for Health Protection(CHP)of Hong Kong,China.Moreover,the effective reproductive number(R_(t))was estimated from wastewater measurements to reflect both citywide and regional transmission dynamics.Our findings demonstrate that large-scale intensive WWS from WWTPs provides cost-effective and timely public health information,especially when the clinical surveillance is inadequate and costly.This approach also provides insights into pandemic dynamics at higher spatiotemporal resolutions,facilitating the formulation of effective control policies and targeted resource allocation. 展开更多
关键词 SARS-CoV-2 Wastewater surveillance PREVALENCE Effective reproductive number
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Flat-footed Females and Missing Males:A New Genus and Species of Pleciofungivoridae(Diptera:Bibionomorpha)Represents the First Record of the Family from Mid-Cretaceous Kachin Amber
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作者 ZHANG Qingqing Wiesław KRZEMINSKI +3 位作者 Jan SEVCIK Vladimir BLAGODEROV Agnieszka SOSZYNSKA Kornelia SKIBINSKA 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2024年第3期541-547,共7页
A new genus and species,Cretopleciofungivora simpsoni gen.et sp.nov.,from the extinct family Pleciofungivoridae(Diptera:Bibionomorpha),is discovered in mid-Cretaceous Kachin amber.Previously,this family was known only... A new genus and species,Cretopleciofungivora simpsoni gen.et sp.nov.,from the extinct family Pleciofungivoridae(Diptera:Bibionomorpha),is discovered in mid-Cretaceous Kachin amber.Previously,this family was known only from imprints in sedimentary rocks of the Jurassic and the Lower Cretaceous.Discovery of a representative of Pleciofungivoridae in Kachin amber confirms the presence of the family in the Upper Cretaceous.The new species has a unique structure of fore tarsus,with lobed and extended tarsal segments Ⅱ to Ⅳ,a feature hitherto known only in a few species of extant Sciaroidea.Although not particularly rare,the new species is currently known only from female specimens.Possible reasons for this phenomenon,very unusual in Sciaroidea,are briefly discussed,including parthenogenesis as a potentially plausible hypothesis. 展开更多
关键词 fungus gnats Sciaroidea Upper Cretaceous Burmese amber swollen tarsomeres
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北京大气重污染过程PM_(10)中水溶性盐的研究 被引量:28
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作者 张凯 王跃思 +3 位作者 温天雪 胡波 刘广仁 Meslmani Yousef 《中国环境科学》 EI CAS CSCD 北大核心 2006年第4期385-389,共5页
利用大气颗粒物快速捕集及化学成分在线分析系统,观测了2004年秋季北京出现的一次长时间严重污染天气过程中PM10的水溶性无机盐浓度的变化.结果表明,PM10中总水溶性无机盐浓度在这次重污染过程中升高了4.7倍.硝酸盐、硫酸盐、铵盐的浓... 利用大气颗粒物快速捕集及化学成分在线分析系统,观测了2004年秋季北京出现的一次长时间严重污染天气过程中PM10的水溶性无机盐浓度的变化.结果表明,PM10中总水溶性无机盐浓度在这次重污染过程中升高了4.7倍.硝酸盐、硫酸盐、铵盐的浓度分别升高7.9,4.1,5.4倍,这3种无机盐的日变化在污染期和非污染期有明显差异.污染期SO2、NOx向SO42-、NO3-转化率明显高于非污染期. 展开更多
关键词 重污染 PM10 硝酸盐 硫酸盐 铵盐
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ADSORPTION OF 2,4-DICHLOROPHENOL IN AQUEOUS SOLUTION ONTO ADSORPTION RESIN MODIFIED BY N-ACETYLANILINE 被引量:7
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作者 费正皓 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2007年第3期263-269,共7页
A hypercrosslinked adsorption resin (ZH-05) modified by N-acetylaniline in the post crosslinking process was prepared. The adsorption properties of ZH-05 toward 2,4-dichlorophenol in comparison with granular activat... A hypercrosslinked adsorption resin (ZH-05) modified by N-acetylaniline in the post crosslinking process was prepared. The adsorption properties of ZH-05 toward 2,4-dichlorophenol in comparison with granular activated carbon (GAC) and Amberlite XAD-4 were observed. The present study mainly focuses on the static equilibrium adsorption behaviors, desorption profiles and the proof of chemisorption. The results show that the Langmuir equation can give a perfect fitting to experimental data, and high temperature was favorable for adsorption of 2,4-dichlorophenol on ZH-05. A related equation was used to correlate the amount of chemisorption and the suppositionai chemisorption equilibrium concentration of adsorbate in aqueous solution. The adsorption capacities from different ranges of temperature and the static desorption experiment both reveal the same conclusion, i.e., the adsorption of 2,4-dichlorophenol from water on ZH-05 is a coexistent process of physical adsorption and chemical transition as on GAC. 展开更多
关键词 Adsorption resin 2 4-DICHLOROPHENOL CHEMISORPTION Chemical modification
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Pyrite Formation in Organic-rich Clay, Calcitic and Coal-Forming Environments 被引量:4
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作者 Gordana DEVI Petar PFENDT +1 位作者 Branimir JOVANIEVI Zoran POPOVIC 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2006年第4期574-588,共15页
The early diagenetic characteristics of pyrite formation processes in a Miocene freshwater sequence of mixed sediments (coal fragments in clays, sandstones or shales) alternating with continuous brown coal layers wa... The early diagenetic characteristics of pyrite formation processes in a Miocene freshwater sequence of mixed sediments (coal fragments in clays, sandstones or shales) alternating with continuous brown coal layers was investigated. Based on abundant minerals, the following main sedimentary environments were distinguished: the illite-montmorillonitic (I-M), calcitic (Ct) and coal-forming environment (CL). For these hydrogeochemically differing environments the effects of limiting factors on the pyrite formation process (availability of sulphate and Fe, amount of organic matter and participation of organic sulphur) were assessed by correlation analysis. Significant differences in the effects of these limiting factors in the particular environments were observed. These differences were explained taking in account the different oxidative activity, Fe-complex and surface complex forming properties of humic substances in dependence of pH of environment and the abundance of sorptionally active clay minerals. In environments having a relatively low pH and containing clay minerals (I-M- and CL-environments) the oxidative activity of humic substances (Hs) on pyrite precursors was greatly prevented however pyrite formation depended on reactive Fe availability as the consequence of complex formation. On the contrary, in environments with a relatively high pH, as it was the calcitic, the oxidative activity of Hs was greatly enhanced, thus oxidizing the sulfur precursors of pyrite. The oxidation degree of organic matter was probably also a consequence of the differing activity of the humic electron-acceptors. 展开更多
关键词 early diagenesis pyrite formation humic electron-acceptors calcitic environment illitemontmorillonitic environment COAL mixed sediments
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Comprehensive Analysis of 9-year Running Data of A^2/O-MBR in Xi an Siyuan University 被引量:8
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作者 Xuemei ZHANG Jingyuan HAO +3 位作者 Qinghua MA Dong LI Bo FU Baolan QIN 《Meteorological and Environmental Research》 CAS 2020年第5期139-143,共5页
Since September 2011,A 2/O-MBR wastewater treatment plant in Xi'an Siyuan University has been successfully running without replacing any of membrane modules.A total of 6.661 million m^3 of campus wastewater has be... Since September 2011,A 2/O-MBR wastewater treatment plant in Xi'an Siyuan University has been successfully running without replacing any of membrane modules.A total of 6.661 million m^3 of campus wastewater has been treated,and 4.405 million m^3 of water reaching the national urban miscellaneous water standard has been reclaimed and reused.A total of 25 km pipeline,5 pits,scenery fountains,lakes,and 12 pump stations have been constructed for flushing toilets,irrigating green grass lawn and afforest,and cleaning hardened pavement.The design and construction of 5 pits,scenery fountains,and lakes are important to meet the national urban miscellaneous water standard under occasional phosphorus and/or nitrogen exceed concentration.The unit water cost is 4.19 yuan/m^3,including membrane modules depreciation and amortization.After the A 2/O-MBR system passes the membrane modules depreciation and amortization period,the unit water cost is 2.82 yuan/m^3.The water productivity of the membrane stack rises first at the beginning of operation,reaches the maximum value,and then decreases.The average annual transmembrane pressure difference increases by 1.12 kPa.The average VMD of industrial permeability decreases annually by 0.45 m^3. 展开更多
关键词 Wastewater treatment and reuse system A 2/O-MBR system Economic feasibility Industrial permeability Membrane fouling
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Effects of ketogenic diet and ketone bodies on the cardiovascular system:Concentration matters 被引量:6
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作者 Souad Nasser Varvara Vialichka +2 位作者 Marta Biesiekierska Aneta Balcerczyk Luciano Pirola 《World Journal of Diabetes》 SCIE 2020年第12期584-595,共12页
Ketone bodies have emerged as central mediators of metabolic health,and multiple beneficial effects of a ketogenic diet,impacting metabolism,neuronal pathologies and,to a certain extent,tumorigenesis,have been reporte... Ketone bodies have emerged as central mediators of metabolic health,and multiple beneficial effects of a ketogenic diet,impacting metabolism,neuronal pathologies and,to a certain extent,tumorigenesis,have been reported both in animal models and clinical research.Ketone bodies,endogenously produced by the liver,act pleiotropically as metabolic intermediates,signaling molecules,and epigenetic modifiers.The endothelium and the vascular system are central regulators of the organism’s metabolic state and become dysfunctional in cardiovascular disease,atherosclerosis,and diabetic micro-and macrovascular complications.As physiological circulating ketone bodies can attain millimolar concentrations,the endothelium is the first-line cell lineage exposed to them.While in diabetic ketoacidosis high ketone body concentrations are detrimental to the vasculature,recent research revealed that ketone bodies in the low millimolar range may exert beneficial effects on endothelial cell(EC)functioning by modulating the EC inflammatory status,senescence,and metabolism.Here,we review the long-held evidence of detrimental cardiovascular effects of ketoacidosis as well as the more recent evidence for a positive impact of ketone bodies—at lower concentrations—on the ECs metabolism and vascular physiology and the subjacent cellular and molecular mechanisms.We also explore arising controversies in the field and discuss the importance of ketone body concentrations in relation to their effects.At low concentration,endogenously produced ketone bodies upon uptake of a ketogenic diet or supplemented ketone bodies(or their precursors)may prove beneficial to ameliorate endothelial function and,consequently,pathologies in which endothelial damage occurs. 展开更多
关键词 Endothelial cells Ketone bodies Vascular physiology β-Hydroxybutyrate β-Hydroxybutyrylation Histone post-translational modifications
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Experimental research on adsorption/desorption for petroleum pollutants in the soil in Daqing oilfield 被引量:1
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作者 Xiaoyan LIU Yingli LI +4 位作者 Guocheng MAO Jungang LI Chun LI Jingxin SUN Qianya ZHU 《Chinese Journal Of Geochemistry》 EI CAS 2006年第B08期260-260,共1页
关键词 大庆市 石油污染 土壤 吸附作用 污染化学
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Calibration of GPS receivers based on IGS and CORS techniques 被引量:1
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作者 SHI Kun QIU Yunfeng +2 位作者 ZHAO Biyun NIE Jin CHEN Yuhan 《Geo-Spatial Information Science》 SCIE EI 2012年第3期213-217,共5页
Concerning the traditional methods,more technical details and more strict conditions are required for global positioning system(GPS)receiver’s calibration especially for mid and long baseline which influenced by the ... Concerning the traditional methods,more technical details and more strict conditions are required for global positioning system(GPS)receiver’s calibration especially for mid and long baseline which influenced by the environment around easily,and more investigations have to be done.In this paper,a new method on how to calibrate GPS receivers is suggested,which is based on the convenient condition that Kunming has one international GPS service station and its own continuously operating reference stations,and the method is confirmed by a test using six different types of GPS receivers.Compared with the traditional methods,the new method is more efficient by decreasing routine calibration works up to 50%. 展开更多
关键词 IGS CORS GPS receiver CALIBRATION BASELINE
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TiO2/EDTA-rich carbon composites: Synthesis, characterization and visible-light-driven photocatalytic reduction of Cr(Ⅵ) 被引量:4
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作者 Zhijun Luo Lingling Qu +4 位作者 Jianzhong Ji Jing wang Suying Jiang Zhiren WU Xiangyang Wu 《Chinese Chemical Letters》 SCIE CAS CSCD 2018年第3期547-550,共4页
TiO2/EDTA-rich carbon composites (TiO2/EDTA-RC) have been successfully synthesized via a low temperature carbonization process. TiO2/EDTA-RC exhibits marked absorption of visible light and excellent photoreduction o... TiO2/EDTA-rich carbon composites (TiO2/EDTA-RC) have been successfully synthesized via a low temperature carbonization process. TiO2/EDTA-RC exhibits marked absorption of visible light and excellent photoreduction of Cr(Ⅵ) activity under visible light irradiation (λ 〉 420 nm). Due to the high carboxyl group content and strong coordination ability of EDTA, TiO2-EDTA complex can be easily fabricated between EDTA incorporated in carbon sheet and titanol group on the surface of TiO2. TiO2- EDTA complexes on the surface of TiO2/EDTA-RC, the LMCT complex, are responsible for the prominent photoreduction of Cr(Ⅵ) properties of TiO2/EDTA-RC under visible light irradiation. In addition, the unique structure of TiO2/EDTA-RC is also propitious to the visible-light photocatalytic reduction of Cr(Ⅵ). Carbon sheet of TiO2/EDTA-RC acts as a supporter. Tio2 nanoparticles and EDTA homogeneously disperse into the carbon sheet supporter and form the TiO2-EDTA complexes, which can avoid the aggregation of TiO2 nanoparticles in the aqueous solution and provide more photocatalytic reaction points for the reduction of Cr(Ⅵ). 展开更多
关键词 TiO2 Carbon-based materials Nanostructures Photocatalysis Reduction of Cr(Ⅵ)
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Forest land use discontinuity and northern red oak Quercus rubra introduction change biomass allocation and life strategy of lingonberry Vaccinium vitis-idaea 被引量:1
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作者 Beata Woziwoda Marcin K.Dyderski Andrzej M.Jagodziński 《Forest Ecosystems》 SCIE CSCD 2021年第1期109-123,共15页
Background:Multi-purpose use of forests in a sustainable way forces a recognition of how introduction of alien woody species in forests with different land use histories affect native plants other than trees.Lingonber... Background:Multi-purpose use of forests in a sustainable way forces a recognition of how introduction of alien woody species in forests with different land use histories affect native plants other than trees.Lingonberry Vaccinium vitis-idaea is an important understory component of temperate and boreal forests and provider of valuable non-wood forest products.Here we studied effects of land use changes and introduction of Northern red oak Quercus rubra on lingonberry in mesic Scots pine forests(in central Poland).We measured lingonberry cover,height of shoots,biomass of stems and leaves,and fruit productivity.Shoots were collected within 200 research plots located in recent and ancient Scots pine forests,with and without Q.rubra.Results:We found that V.vitis-idaea reached lower cover,aboveground biomass and fruit production in recent than ancient forests and in forests with than without Q.rubra.The fruit production in recent pine forest was only 2%of that reported in ancient pine forest,and V.vitis-idaea did not reproduce generatively in forests with Q.rubra.Biomass and carbon sequestration of V.vitis-idaea in forests with alien(invasive)trees decreased by 75%compared to ancient pine forest.Effects were also clear at the individual shoot level–in less suitable conditions we found taller heights and higher biomass allocation into stems than foliage.Biomass allocation in fruiting and non-fruiting shoots in pine forests was also different–less of the dry biomass of fruiting shoots was allocated to leaves than to stems.Conclusions:In the age of high interest in ecosystem services and discussions about usage of alien tree species as alternatives in forest management,our results clearly indicate disruption of ecosystem services provided by V.vitisidaea in the presence of Q.rubra.Lingonberry benefited from the continuity of forest land use,however,regardless of land-use legacy,alien tree introduction led to decline in abundance of species crucial for ecosystem functioning.Therefore,to maintain valuable native species and for conservation of ecosystem services delivery,we suggest limiting the introduction of Q.rubra in areas with abundant V.vitis-idaea,especially in forests with continuous forest land-use history. 展开更多
关键词 Ancient and recent forest Understory biomass Ecosystem services Invasive tree LINGONBERRY Non wood forest products Red oak introduction Scots pine monoculture
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Heavy Metals Contamination in Greenhouse Soils and Vegetables in Guanzhong, China 被引量:2
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作者 Ling Liu Jinyin Lu +3 位作者 Zhenwen Zhang Hai Zheng Xiaoqing Gao Wei Zhang 《Journal of Encapsulation and Adsorption Sciences》 2014年第3期80-88,共9页
This study used a flame atomic absorption spectrometer (FAAS) and atomic fluorescence spec-trophotometer (AFS) to detect the concentrations of chromium (Cr), cadmium (Cd), lead (Pb), hy-drargyrum (Hg) and arsenic (As)... This study used a flame atomic absorption spectrometer (FAAS) and atomic fluorescence spec-trophotometer (AFS) to detect the concentrations of chromium (Cr), cadmium (Cd), lead (Pb), hy-drargyrum (Hg) and arsenic (As) in soils and three genotypes of vegetables in greenhouse, as well as analyzed the physical and chemical properties of soils, including soil pH, soil organic matter (OM), basic nutrients, electrical conductivity (EC) and cation exchange capacity (CEC) in Guan- zhong areas, Shaanxi province, China. The results showed that comparing to subsoil, the sampled topsoil is enriched in Cr, Cd, Pb, As and Hg. Cd (0.83 - 3.17 mg·kg-1) and Hg (0.40 - 1.44 mg·kg-1) are exceeding the limited value stated in “the 2006 Greenhouse Vegetable Producing Environmental Quality Evaluation Standards” of 0.40 mg·kg-1 and 0.35 mg·kg-1 respectively. However, Nanzhuang greenhouse soil is within the limits. The heavy metal pollution index (HPI) of soil in Sanyuan (8.10) is the highest and in Dongzhang (4.23) is the lowest. The contents of Pb (0.201 - 0.376 mg·kg-1) were exceeding the limited value (0.20 mg·kg-1) in vegetables species, and Cd (0.0363 - 0.0572 mg·kg-1) in some place were also exceeding the limited value (0.05 mg·kg-1). Greenhouse soils were becoming acidified year after year;the ratios of N, P and K in soil were seriously imbalanced. According to the impacting factors, OM, pH, available P, EC and CEC have obviously effected the accumulation of Cr and Hg. However, there was not enough evidence for the effects of available nitrogen and available potassium. 展开更多
关键词 HEAVY Metals SOILS VEGETABLES GREENHOUSE
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Microstructure characterization and electrochemical corrosion behavior of Zn and Zn/Mg alloys in H_2SO_4 solution
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作者 S.H.Ettefagh Far A.Rahimi +1 位作者 M.Chaghazardi A.Davoodi 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第6期2007-2013,共7页
The three systems of pure Zn, Zn-0.10% Mg(mass fraction), and Zn-0.15% Mg(mass fraction) were cast under controlled atmosphere and their microstructures were characterized by SEM/EDS analysis. The electrochemical corr... The three systems of pure Zn, Zn-0.10% Mg(mass fraction), and Zn-0.15% Mg(mass fraction) were cast under controlled atmosphere and their microstructures were characterized by SEM/EDS analysis. The electrochemical corrosion behavior of these three samples was examined in the very aggressive solution of 50% H2SO4(mass fraction) using electrochemical impedance spectroscopy(EIS) and potentiodynamic polarization measurements. The results show that magnesium improves in some extent the corrosion resistance of pure Zn in 50% H2SO4(mass fraction) confirmed by EIS test. Results of polarization measurment also demonstrate that small amount of Mg significantly improves the passivation of Zn in the test solution. Results of surface morphology of the samples and EDS analysis reveal that Mg reduced the corrosion attacks to pure Zn. 展开更多
关键词 COMPOSITES CORROSION zinc-magnesium alloys potentiodynamic polarization electrochemical impedance spectroscopy
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Advances on bioremediation of oil-contaminated soil in cold region
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作者 Xiaoyan LIU Jingxin SUN +4 位作者 Guocheng MAO Chunlei DAI Chun LI Qianya ZHU Yingli LI 《Chinese Journal Of Geochemistry》 EI CAS 2006年第B08期96-97,共2页
关键词 寒冷地区 土壤污染 石油 生物降解作用
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Bacterial signal C10-HSL stimulates spore germination of Galactomyces geotrichum by transboundary interaction
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作者 Xin Lu Yue Wang +2 位作者 Zhixuan Feng Liang Fu Dandan Zhou 《Chinese Chemical Letters》 SCIE CAS CSCD 2023年第4期374-377,共4页
The coevolution and coexistence of bacterial–fungal consortium have been widely reported in various natural ecosystems. The transboundary communication mediated by bacterial acyl–homoserine lactone signals probably ... The coevolution and coexistence of bacterial–fungal consortium have been widely reported in various natural ecosystems. The transboundary communication mediated by bacterial acyl–homoserine lactone signals probably is the driving force of fungal spore germination. This study aimed to report a functional bacterial signal molecule, C10-acyl homoserine lactone, which could be sensed by Galactomyces geotrichum. The spore germination rates of G. geotrichum increased by 22%. Meanwhile, carbohydrate production improved by 1.0-to 2.5-fold. G. geotrichum signaled to C10-HSL through receptor gene Rho1and made a response in cell wall assembly and carbohydrate biosynthesis by the upregulated expression(above 1-fold) of functional genes, such as Smi1, Utr2, and Chs2. It contributed to spore germination and morphology transformation together. This study provides a novel perspective for understating the transboundary cooperation between fungi and bacteria by cell-to-cell communication. 展开更多
关键词 Cell wall C10-HSL Galactomyces geotrichum Spore germination Transboundary communication
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Happy together? Avoidance of conspecifics by gregarious mussels
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作者 Anna DZIERZYNSKA-BIALONCZYK Aleksandra SKRZYPCZAK Jaroslaw KOBAK 《Current Zoology》 SCIE CAS CSCD 2018年第1期53-61,共9页
Zebra mussel Dreissena polymorpha is a Ponto-Caspian species invasive in Europe and North America, with great environmental impact. It lives byssally attached to hard substrata in large aggregations, which is often ex... Zebra mussel Dreissena polymorpha is a Ponto-Caspian species invasive in Europe and North America, with great environmental impact. It lives byssally attached to hard substrata in large aggregations, which is often explained by its preferences for conspecifics, though direct evidence for such preferences has been rather limited so far. We studied the reactions of zebra mussels to con- specifics, hypothesizing that they may either be attracted to one another or form aggregations only in the absence of alternative attachment sites, in Experiment 1, we tested mussel tendency to detach from existing druses depending on druse size (2-25 individuals) and substratum type (soft: sand; hard: glass). Mussels detached significantly more often on the hard substratum and from larger druses compared to soft substratum and smaller druses, respectively. This indicates that mussels tended to avoid conspecifics at high density, particularly when alternative substratum was available. In Experiment 2, we tested the responses of single mussels to distant (3 or 15cm) conspecifics (0, 3, 15 individuals per 2.51 tank) on the sandy substratum. The presence of conspecifics, regardless of their distance and density, resulted in single unattached mussels staying more often in their initial positions. Mussels did not move preferentially towards or away from the conspecifics. Thus, even on unsuitable substratum mussels were not attracted by conspecifics and probably exhibited an avoidance reaction by reducing their movement. This suggests that dense mussel aggregations are formed due to the lack of available alternative attachment sites rather than due to their preferences for conspecifics. 展开更多
关键词 active detachment Dreissena polymorpha movement mussel aggregations zebra mussel.
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