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Post-processing of chitosan based nanofibers prepared by electrospinning

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Post-processing of chitosan based nanofibers prepared by ele...

Response of PM_(2.5)-bound elemental species to emission variations and associated health risk assessment during the COVID-19 pandemic in a coastal megacity

第八届中国功能材料及其应用学术会议

作者： SUN Kang GE Yuan-xin LI Zhong-hui ZHANG Xiao-lin Institute of Applied Chemistry Chengdu normal university environmental monitoring station of Minhang district

ISBN: (纸本)9783037859698

Recently,electrospinning of nanofibers based on chitosan has been widely studied and numerous chitosan based nanofibers have been prepared,for the enormous possibilities of applications in various areas such as filtration,enzyme immobilization,tissue engineering,wound dressing,drug delivery,and *** most of the chitosan based nanofibers are soluble in aqueous solutions and the other properties such as mechanical properties are not suitable for the further *** is necessary to improve the properties of chitosan based *** post-processing has been done to the chitosan based nanofibers and many post-processing products have *** article discusses the post-processing of the chitosan based nanofibers involving methods,mechanisms,changes of nanofiber properties,and applications of the post-processing products in *** post-processing is divided into alkali treatment,crosslinking,and functionalizing.

关键词： chitosan nanofiber electrospinning postprocessing application

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Journal of environmental Sciences 2022年第12期34卷 115-127页

作者： Guochen Wang Kan Huang Qingyan Fu Jia Chen Juntao Huo Qianbiao Zhao Yusen Duan Yanfen Lin Fan Yang Wenjie Zhang Hao Li Jian Xu Xiaofei Qin Na Zhao Congrui Deng Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention(LAP3) Department of Environmental Science and EngineeringFudan UniversityShanghai 200433China Shanghai environmental monitoring Center Shanghai 200030China pudong new district environmental monitoring station Shanghai 200122China Chinese Research Academy of environmental Sciences Beijing 100012China IRDR ICoE on Risk Interconnectivity and Governance on Weather/Climate Extremes Impact and Public Health Fudan UniversityShanghai 200433China Institute of Eco-Chongming(IEC) Shanghai 202162China

The coronavirus(COVID-19)pandemic is disrupting the world from many *** this study,the impact of emission variations on PM_(2.5)-bound elemental species and health risks associated to inhalation exposure has been analyzed based on real-time measurements at a remote coastal site in Shanghai during the *** trace elemental species decreased significantly and displayed almost no diel peaks during the *** the lockdown,they rebounded rapidly,of which V and Ni even exceeded the levels before the lockdown,suggesting the recovery of both inland and shipping *** sources were identified based on receptor *** combustion accounted for more than 70%of the measured elemental concentrations before and during the *** emissions,fugitive/mineral dust,and waste incineration all showed elevated contributions after the *** total non-carcinogenic risk(HQ)for the target elements exceeded the risk threshold for both children and adults with chloride as the predominant species contributing to ***,the total carcinogenic risk(TR)for adults was above the acceptable level and much higher than that for *** incineration was the largest contributor to HQ,while manufacture processing and coal combustion were the main sources of *** control measures were beneficial for lowering the carcinogenic risk while unexpectedly increased the non-carcinogenic *** the perspective of health effects,priorities of control measures should be given to waste incineration,manufacture processing,and coal combustion.A balanced way should be reached between both lowering the levels of air pollutants and their health risks.

关键词： COVID-19 lockdown PM_(2.5)-bound elemental species Source apportionment Health risk Shanghai

Drip fertigation and plant hedgerows significantly reduce nitrogen and phosphorus losses and maintain high fruit yields in intensive orchards

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Journal of Integrative Agriculture 2023年第2期22卷 598-610页

作者： SONG Ke QIN Qin YANG Ye-feng SUN Li-juan SUN Ya-fei ZHENG Xian-qing Lü Wei-guang XUE Yong Eco-environmental Protection Research Institute Shanghai Academy of Agricultural SciencesShanghai 201403P.R.China pudong new district Agro-Technology Extension Service Center Shanghai 201300P.R.China

A field experiment was carried out to evaluate the effects of drip fertigation combined with plant hedgerows on nitrogen and phosphorus runoff losses in intensive pear orchards in the Tai Lake *** and phosphorus runoff over a whole year were measured by using successional runoff water collection *** four experimental treatments were conventional fertilization(CK),drip fertigation(DF),conventional fertilization combined with plant hedgerows(C+H),and drip fertigation combined with plant hedgerows(D+H).The results from one year of continuous monitoring showed a significant positive correlation between precipitation and surface runoff *** runoff discharge under the treatments without plant hedgerows totaled 15.86%of precipitation,while surface runoff discharge under the treatments with plant hedgerows totaled 12.82%of *** hedgerows reduced the number of runoff events and the amount of surface *** is the main driving force for the loss of nitrogen and phosphorus in surface runoff,and fertilization is an important factor affecting the losses of nitrogen and *** CK,approximately 7.36%of nitrogen and 2.63%of phosphorus from fertilization entered the surface water through *** fertigation reduced the accumulation of nitrogen and phosphorus in the surface soil and lowered the runoff loss concentrations of total nitrogen(TN)and total phosphorus(TP).Drip fertigation combined with plant hedgerows significantly reduced the overall TN and TP losses by 45.38 and 36.81%,respectively,in comparison to the CK *** fertigation increased the vertical migration depth of nitrogen and phosphorus nutrients and reduced the accumulation of nitrogen and phosphorus in the surface soil,which increased the pear *** promotion of drip fertigation combined with plant hedgerows will greatly reduce the losses of nitrogen and phosphorus to runoff and maintain the high fruit yields in the intensive orchards of

关键词： drip fertigation plant hedgerows surface runoff nitrogen and phosphorus losses fruit yields

Aqueous-phase formation of N-containing secondary organic compounds affected by the ionic strength

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Journal of environmental Sciences 2024年第4期138卷 88-101页

作者： Yuqi Gan Xiaohui Lu Shaodong Chen Xinghua Jiang Shanye Yang Xiewen Ma Mei Li Fan Yang Yewen Shi Xiaofei Wang Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention Department of Environmental Science and EngineeringFudan UniversityShanghai 200433China Shanghai Institute of Pollution Control and Ecological Security Shanghai 200092China Guangdong Provincial Observation and Research station for Coastal Atmosphere and Climate of the Great Bay Area Southern University of Science and TechnologyShenzhen 518055China Institute of Mass Spectrometry and Atmospheric Environment Guangdong Provincial Engineering Research Center for On-line Source Apportionment System of Air PollutionJinan UniversityGuangzhouChina environmental monitoring station of pudong new district Shanghai 201200China Shanghai Municipal Center for Disease Control&Prevention Shanghai 200336China

The reaction of carbonyl-to-imine/hemiaminal conversion in the atmospheric aqueous phase is a critical pathway to produce the light-absorbing N-containing secondary organic compounds(SOC).The formation mechanism of these compounds has been wildly investigated in bulk solutions with a low ionic ***,the ionic strength in the aqueous phase of the polluted atmosphere may be *** is still unclear whether and to what extent the inorganic ions can affect the SOC *** we prepared the bulk solution with certain ionic strength,in which glyoxal and ammonium were mixed to mimic the aqueous-phase *** characterization by High-resolution Mass Spectrometry was performed to identify the N-containing products,and the light absorption of the mixtures was measured by ultraviolet-visible ***-nine N-containing compounds were identified and divided into four categories(N-heterocyclic chromophores,high-molecular-weight compounds with N-heterocycle,aliphatic imines/hemiaminals,and the unclassified).It was observed that the longer reaction time and higher ionic strength led to the formation of more N-heterocyclic chromophores and the increasing of the lightabsorbance of the *** added inorganic ions were proposed to make the aqueous phase somewhat viscous so that the molecules were prone to undergo consecutive and intramolecular reactions to form the *** general,this study revealed that the enhanced ionic strength and prolonged reaction time had the promotion effect on the lightabsorbing SOC *** implies that the aldehyde-derived aqueous-phase SOC would contribute more light-absorbing particulate matter in the industrial or populated area where inorganic ions are abundant.

关键词： Ionic strength Carbonyl-to-imine/hemiaminal Heterocyclic Brown carbon Mass spectrometry Aqueous-phase reaction

Mixing states and secondary formation processes of organic nitrogen-containing single particles in Guangzhou,China

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Journal of environmental Sciences 2024年第4期138卷 62-73页

作者： Lijun Yun Chunlei Cheng Suxia Yang Zaihua Wang Mei Li Qi En Zhong LiyuanMao Sulin Liu Xiaoya Cheng Duanying Chen Fan Yang Zhen Zhou Institute of Mass Spectrometry and Atmospheric Environment Guangdong Provincial Engineering Research Center for on-line source apportionment system of air pollutionJinan UniversityGuangzhou 510632China Guangdong-Hongkong-Macao Joint Laboratory of Collaborative Innovation for environmental Quality Guangzhou 510632China State Key Laboratory of Loess and Quaternary Geology Institute of Earth EnvironmentChinese Academy ScienceXi’an 710061China Institute for Environment and Climate Research Jinan UniversityGuangzhou 510632China Guangdong Academy of Sciences Institute of Resources Utilization and Rare Earth DevelopmentGuangzhou 510650China environmental monitoring station of pudong new district Shanghai 201200China

Organic nitrogen(ON)compounds play a significant role in the light absorption of brown carbon and the formation of organic aerosols,however,the mixing state,secondary formation processes,and influencing factors of ON compounds are still *** paper reports on the mixing state of ON-containing particles based on measurements obtained using a highperformance single particle aerosol mass spectrometer in January 2020 in *** ON-containing particles accounted for 21% of the total detected single particles,and the particle count and number fraction of the ON-containing particles were two times higher at night than during the *** prominent increase in the content of ON-containing particles with the enhancement of NO_xmainly occurred at night,and accompanied by high relative humidity and nitrate,which were associated with heterogeneous reactions between organics and gaseous NO_(x)and/or NO_(3)*** synchronous decreases in ON-containing particles and the mass absorption coefficient of water-soluble extracts at 365 nm in the afternoon may be associated with photo-bleaching of the ON species in the *** addition,the positive matrix factorization analysis found five factors dominated the formation processes of ON particles,and the nitrate factor(33%)mainly contributed to the production of ON particles at *** results of this study provide unique insights into the mixing states and secondary formation processes of the ON-containing particles.

关键词： Organic nitrogen compounds Single particles Mixing state Secondary formation Nighttime chemistry

Studies on Ecological monitoring of Plant Community and Plant Diversity in Shenzhen, Southern China

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Open Journal of Forestry 2021年第4期11卷 352-380页

作者： Yuyuan Huang Xinfan Yu Hong Liang Zhiming Yang Haiyang Wen Zhen Ye Yunhe Lu Ruoyu Wei Lijun Yang Song Ma Kangsai Zhao Fan Wang Zhijie Chen Huina Yang Chengxi Jiang Bin Xu Weimin Wang Wang Xu Zhu Ming Shizhen Lin Hao Liu Hualiang Luo Suni Deng Lijuan Huang Yanjun Lei Xiaoli Wan Yahe Li Wanmin Zhou Shun Zhao Zhenliang Duan Dongyao Liao Xiaobo Qiu Haoqun Huang Linlin Jiang College of Agriculture and Biology Zhongkai University of Agriculture and Engineering Guangzhou China Shenzhen environmental monitoring Center Shenzhen China South China Institute of environmental Sciences Ministry of Ecology and Environment Guangzhou China environmental monitoring station of Nanshan district Shenzhen China Ecological and environmental Protection monitoring station of Dapeng district Shenzhen China Construction Public Service Bureau of Dapeng new district Shenzhen China

From Jan. 2013 to Nov. 2018, we carried out the investigation on vegetation studies in the ecological monitoring programs, Shenzhen and totally researched 170 plant communities of mountain areas etc., few areas of street regions and parks etc., for communities’ structural characteristics and plant diversity. We comparatively analyzed natural forests, semi-natural forest and artificial forest composition and structural characters and family, genus and species diversity level and the main affected factors. We also researched and analyzed these communities’ structural characteristics and pant diversity, comparatively analyzed natural forests, semi-natural forest and artificial forest composition and structural characters and family, genus and species diversity level, the main affected factors;researched and analyzed the relationship between plant community structure characteristics with the absorbing ability to PM2.5 pollutants. The result showed that the structure and plant diversity of natural forest were obviously better than artificial disturbed forest or artificial forest, the semi-natural forest was the middle level of the forests, In the indices of height, DBH, coverage and crow width etc. of tree layer, natural forests and semi-natural forests were obvious

关键词： Shenzhen Vegetation Community Structure Diversity PM2.5 Ecological monitoring Natural Forest Artificial Forest

Comprehensive Management and Protection of Lakes in Kaifeng

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Meteorological and environmental Research 2015年第2期6卷 25-28页

作者： Wang Guanghua Kaifeng environmental monitoring station

Through analysing pollution source and status quo of the main lakes in Kaifeng,such as Dragon Pavilion Lake and Baogong Lake,the conclusion is that Kaifeng＇s lake environment has been in a greater pollution condition. For lake pollution situation,we put forward comprehensive management and protection approaches of lakes,including the relocation of businesses around the lake,plugging the sewage outfall surrounding lakes,dredging and deeply digging to increase the water environment capacity of lake. By dredging the river,the lakes in urban district connect together. Controlling aquaculture scale of lakes,the ecological function of the lake is played. Constructing drainage network around the lake,integration of landscape and lake flood control is formed. Adding new water into lakes,stagnant water becomes flowing water. We sum up the experience of lake management and protection： strengthening protection awareness is the key; lake remediation is the fundamental; attention to ecological protection of the lake is the most important factor in the development of lakes; exploiting a variety of functions of the lakes including landscaping,tourism,recreation,aquaculture,public health is the goal.

关键词： Kaifeng City Lake management and protection Pollution China

Interaction of DNA with aromatic hydrocarbons fraction in atmospheric particulates of Xigu district of Lanzhou,China

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Journal of environmental Sciences 2007年第8期19卷 948-954页

作者： GAO Hong MA Min-quan ZHOU Lei JIA Run-ping CHEN Xing-guo HU Zhi-de Key Laboratory of Western China＇s environmental Systems （Ministry of Education） College of Earth and Environment Sciences Lanzhou University Lanzhou 730000 China. Lanzhou environmental monitoring station Lanzhou 730000 China Department of Chemistry Lanzhou University. Lanzhou 730000 China

Voluminously epidemiological studies show that the relationships exist between the air pollution and human health and cancer. Aromatic hydrocarbons （AHs） in air form a large class of organic pollutants, which are widely in environment and many of them are known to be carcinogenic and/or mutagenic and contribute to ambient air pollution. In the past decades, bioassays mainly have been used to evaluate the toxicity of chemical mixtures in atmospheric particulates or aqueous environment. However, it is well known that the covalent complexes formed by carcinogens with DNA may be exert negative results in bioassay. So the main aim of this paper is to develop an evaluation method of toxicity effects of chemical mixtures in atmospheric particulates from chemical standpoint. In this study, the in vitro interaction of the AHs with DNA was investigated by absorption, fluorescence and resonance light scattering （RLS） spectroscopic techniques. The results showed that the AHs in the atmospheric particulates could combine with calf thymus DNA （ctDNA） and herring sperm DNA （hsDNA） without being activated or metabolized by organism, respectively. Intercalation may be present in the mechanism of interaction. The binding constants of the AHs with ctDNA and hsDNA were 2.5x102 and 2.0x103, respectively, which indicated that the interaction of the AHs with hsDNA is stronger than that with ctDNA. In addition, the relationships of dose-effect between the total mole concentration of chemical components and the ability of binding ctDNA and hsDNA were confirmed. This research made it possible to study the toxicity effects of chemical mixtures in atmospheric particulates by chemical method. It is believed that the composition and contents of unknown AHs and the interaction of DNA with AHs in atmospheric particulates of Xigu district of Lanzhou City, China are first reported in the past twenty years.

关键词： atmospheric particulates aromatic hydrocarbons fraction interaction with DNA

Analysis of the Current Water Environment Quality of Xiaoquan Tributary in Ba'nan district

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Asian Agricultural Research 2015年第3期7卷 80-81 88,88页

作者： Shuang HU Ba'nan environmental monitoring station

With the class V water standards of Surface Water Quality Standards( GB3838-2002) as a basis for evaluation,this paper monitors the water quality of Hongqi Village and Hongxing Village monitoring sections in Xiaoquan tributary of Huaxi River,and uses the single factor index method for *** monitoring results show that the water quality of the two sections falls within inferior class V,and Xiaoquan tributary can not meet the water functional *** main reason for pollution lies in the pollution from the upstream sewage,and it is recommended to strengthen inter-regional water pollution control coordination mechanism and effectively address river pollution problems.

关键词： Ba’nan district Xiaoquan tributary Water environme