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Theoretical Researches on the Recognizing Characteristics of Atrazine Imprinted Polymers with Different Functional Monomers

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Chinese Journal of Structural Chemistry 2012年第12期31卷 1794-1802页

作者：刘俊渤孙佳妮唐珊珊陈凯尹靳瑞发 College of resource and environmental Science Jilin Agricultural University department of Chemistry Chifeng University

As a widely used herbicide, the threat of atrazine to both environment and health of people has become the focus. Therefore, the research and analysis of atrazine are getting more important. In this work, the MIT was used to detect atrazine theoretically. Atrazine was taken as a template molecule. MAA, MMA and TFMAA were taken as the functional monomers, respectively. The geometry optimization, the nature of hydrogen bonds, the NBO charge, and the binding energies of the imprinted molecule with the functional monomers were investigated at the B3LYP/6-31g（d,p） level. Results indicated that atrazine had the strongest interaction with TFMAA. When the ratio of atrazine and TFMAA was 1：6, the amount of H-bond formed from atrazine and TFMAA was the largest. Moreover, TFMAA owned the largest binding energy with atrazine while MMA owned the smallest. The study is helpful to interpret experiment phenomena of molecular imprinting and select better functional monomers.

关键词： atrazine molecular-imprinted polymer hydrogen bonds density functional theory

Comparative Mountain Hydrology: A Case Study of Wis?ok River in Poland and Chaohe River in China

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Chinese Geographical Science 2015年第1期25卷 1-12页

作者： Leszek SOBKOWIAK LIU Changming department of Hydrology and Water management Institute of Physical Geography and Environmental Planning Adam Mickiewicz University Institute of Geographic Sciences and natural resources Research Chinese Academy of Sciences

Hydrological processes in river basins of similar size and morphology may differ significantly due to different climatic conditions. This paper presents a comparative analysis of hydrological characteristics of two river basins located in different climatic zones: the Wisok River Basin in the south-eastern Poland and the Chaohe River Basin in the northern China. The criteria of their choice were similarities in the basin area, main river length and topography. The results show that climate plays a key role in shaping fluvial conditions within the two basins. It is concluded that: 1) precipitation in the Wisok River Basin is more evenly distributed in the yearly cycle, while in the Chaohe River Basin it is highly concentrated in the few summer months; 2) spring snowmelt significantly contributes to runoff in the Wisok River Basin, while its role in the Chaohe River Basin is negligible; 3) in the Wisok River Basin, besides the peak flow in spring, there is also a period of high water in summer resulting from precipitation, while in the Chaohe River Basin there is only one high water period in summer; 4) the Wisok River Basin shows relatively higher stability in terms of the magnitude of intra- and inter-seasonal discharges; 5) during the multi-year observation period, a decrease in both precipitation and runoff was recorded in the two river basins.

关键词： comparative hydrology mountain area Wislok River Basin Chaohe River Basin seasonal changes inter-annual changes

Degradation of micropolluants in flow-through VUV/UV/H2O2 reactors: Effects of H2O2 dosage and reactor internal diameter

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Journal of environmental Sciences 2021年第12期33卷 28-37页

作者： Lumeng Zhan Wentao Li Li Liu Tao Han Mengkai Li Zhimin Qiang 无 Key Laboratory of Drinking Water Science and Technology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China department of Geosciences and natural resource management University of CopenhagenFrederiksberg C 1985Denmark Sino-Danish College University of Chinese Academy of SciencesBeijing 100049China School of environmental Science and Engineering Qingdao UniversityQingdao 266071China

The degradation of atrazine (ATZ),sulfamethoxazole (SMX) and metoprolol (MET) in flowthrough VUV/UV/H2O2reactors was investigated with a focus on the effects of H2O2dosage and reactor internal diameter (ID).Results showed that the micropollutants were degraded efficiently in the flow-through VUV/UV/H2O2reactors following the pseudo first-order kinetics (R2>0.92).However,the steady-state assumption (SSA) kinetic model being vital in batch reactors was found invalid in flow-through reactors where fluid mixing was less *** the increase of H2O2dosage,the ATZ removal efficiency remained almost constant while the SMX and MET removal was enhanced to different extents,which could be explained by the different reactivities of the pollutants towards HO·.A larger reactor ID resulted in lower degradation rate constants for all the three pollutants on account of the lower average fluence rate,but the change in energy efficiency was much more *** reality,the electrical energy per order (EEO) of the investigated VUV/UV/H2O2treatments ranged between 0.14–0.20,0.07–0.14 and 0.09–0.26 k Wh/m3/order for ATZ,SMX and MET,respectively,with the lowest EEOfor each pollutant obtained under varied H2O2dosages and reactor *** study has demonstrated the efficiency of VUV/UV/H2O2process for micropollutant removal and the inadequacy of the SSA model in flow-through reactors,and elaborated the influential mechanisms of H2O2dosage and reactor ID on the reactor performances.

关键词： VUV/UV/H2O2 Flow-through reactor Degradation H2O2 dosage Reactor internal diameter

Simple model of sludge thickening process in secondary settlers

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Frontiers of environmental Science & Engineering 2016年第2期10卷 319-326页

作者： Yuankai ZHANG Hongchen WANG Lu QI Guohua LIU Zhijiang HE Songzhu JIANG School of Environment & natural resource Renmin University of China Beijing 100872 China

In wastewater treatment plants （WWTPs）, a secondary settler acts as a clarifier, sludge thickener, and sludge storage tank during peak flows and therefore plays an important role in the performance of the activated sludge process. Sludge thickening occurs in the lower portions of secondary clarifiers during their operation. In this study, by detecting the hindered zone from the complete thickening process of activated sludge, a simple model for the sludge thickening velocity, us = aXb （ a =0.9925SSFI3.5, b = - 3.5411n（ SS VI3.5 ）＋12.973）, describing the potential and performance of activated sludge thickening in the hindered zone was developed. However, sludge thickening in the compression zone was not studied because sludge in the compression zone showed limited thickening. This empirical model was developed using batch settling data obtained from four WWTPs and validated using measured data from a fifth WWTP to better study sludge thickening. To explore different sludge settling and thickening mechanisms, the curves of sludge thickening and sludge settling were compared. Finally, it was found that several factors including temperature, stirring, initial depth, and polymer conditioning can lead to highly concentrated return sludge and biomass in a biologic reactor.

关键词： wastewater treatment plants secondary settler,sludge thickening sludge settling hindered zone

Heavy Metals and PAHs in Sewage Sludge from Twelve Wastewater Treatment Plants in Zhejiang Province

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Biomedical and environmental Sciences 2008年第4期21卷 345-352页

作者： C. M. TIENTCHEN College of environmental and resource Sciences Zhejiang University

Objective To investigate the heavy metals （HMs） and polycyclic aromatic hydrocarbons （PAHs） in sludge of twelve wastewater treatment plants （WWTPs） in Zhejiang province of China, and to assess their potential for land application. Methods Sludge was collected from 12 WWTPs within the province. GC-MS and AAS were used to measure PAHs and HMs contents in sludge. Results Concentrations of HMs in most of the sludge samples were below the regulatory limits for the sludge to be used in agriculture in China with the exception of Zn in 2 sludge samples and Cd in 1 sample. All 16 PAHs, targeted by the USEPA agency, were found in the sludge from the twelve plants with a total concentration ranging from 33.73 mg kg^-1 to 82.58 mg kg^-1 （dry weight, d.w.）. The levels of Σ9 PAHs varied from 13.87 mg kg^-1 to 61.86 mg kg^-1 （d.w.） in the sludge, far exceeding the limitation value recommended by the Europe Union. The concentration and composition of PAHs in sewage sludge varied and depended mainly on the quantity and type of industrial wastewater accepted by the WWTPs. A significant relationship between the proportion of industrial wastewater received by WWTPs and the total content of 16 PAHs in the sludge was observed. Conclusion PAHs have become one of the primary pollutants in sludge of Zhejiang WWTPs instead of HMs. It is, therefore, essential to reduce the contents of PAHs before the sludge can be used in agriculture through proper treatment.

关键词： Sludge Heavy Metal Chemical Fractions Polycyclic aromatic hydrocarbons Contribution

Uptake and accumulation of phenanthrene and pyrene in spiked soils by Ryegrass(Lolium perenne L.)

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Journal of environmental Sciences 2005年第5期17卷 817-822页

作者： XU Sheng-you CHEN Ying-xu LIN Qi WU Wei-xiang XUE Sheng-guo SHEN Chao-feng department of environmental Engineering Zhejiang University Hangzhou 310029 China department of resource and Environment Huangshan University Huangshan 245000 China

Phytoremediation has long been recognized as a cost-effective method for the removal of polycyclic aromatic hydrocarbons （PAHs） from soil. A study was conducted to investigate the uptake and accumulation of PAHs in root and shoot of Lolium perenne L. Pot experiments were conducted with series of concentrations of 3.31-378.37 mg/kg for phenanthrene and those of 4.22-365.38 mg/kg for pyrene in a greenhouse. The results showed that both ryegrass roots and shoots did take up PAHs from spiked soils, and generally increased with increasing concentrations of PAH in soil. Bioconcentration factors（BCFs） of phenanthrene by shoots and roots were 0.24- 4.25 and 0.17-2.12 for the same treatment. BCFs of pyrene by shoots were 0.20-1.5, except for 4.06 in 4.32 mg/kg treatment, much lower than BCFs of pyrene by roots （0.58-2.28）. BCFs of phenanthrene and pyrene tended to decrease with increasing concentrations of phenanthrene and pyrene in soil. Direct uptake and accumulation of these compounds by Lolium perenne L. was very low compared with the other loss pathways, which meant that plant-promoted microbial biodegradation might be the main contribution to plant-enhanced removal of phenanthrene and pyrene in soil. However, the presence of Lolium perenne L. significantly enhanced the removal of phenanthrene and pyrene in spiked soil. At the end of 60 d experiment, the extractable concentrations of phenanthrene and pyrene were lower in planted soil than in non-planted soil, about 83.24%-91.98% of phenanthrene and 68.53%-84.10% of pyrene were removed from soils, respectively. The results indicated that the removal of PAHs in contaminated soils was a feasible approach by using Lolium perenne L.

关键词： phytoremediation polycyclic aromatic hydrocarbons(PAHs) phenanthrene and pyrene uptake and accumulation

Variation of karst spring discharge in the recent five decades as an indicator of global climate change: A case study at Shanxi, northern China

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Science China Earth Sciences 2005年第11期48卷 2001-2010页

作者： GUO Qinghai1, WANG Yanxin1, MA Teng1 & LI Luxiu2 1. School of environmental Studies, China University of Geosciences, Wuhan 430074, China 2. Office of Water resource management of Shanxi Province, Taiyuan 030001, China School of environmental Studies China University of Geosciences Wuhan China Office of Water resource management of Shanxi Province Taiyuan China

Karst in Shanxi Province is representative of that in northern China, and karst water systems discharge in the form of springs that are among the most important sources for local water supply. Since the 1950s, attenuation has been the major trend of discharge variation of most karst springs at Shanxi. Based on the case study of 7 karst springs including Niangziguan, Xin’an, Guozhuang, Shentou, Jinci, Lancun, and Hongshan springs, the discharge variation process of karst springs was divided into natural fluctuation phase and anthropogenic impact phase. Discharge attenuation of the 7 karst springs was controlled mainly by climate and human activities, with their contributions being respectively about 60% and 40%. According to the dif-ference of the effect of climate and human activities for each spring, attenuation modes of spring discharge fall into three types: natural process dominated attenuation type, exploitation induced process dominated attenuation type, and mixed attenuation type. The total restored discharge variation of 7 karst springs matched well with the global air temperature change in 1956―2000, clearly indicating the trend of global warming and aridity in the last several decades, and the analysis of discharge variation processes of karst springs can be used as a new tool for global change studies.

关键词： karst, Shanxi, spring discharge, attenuation, climate, human activity, global change

Vegetation composition differentiation and species-environment relationships in the northern part of Isfahan Province, Iran

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Journal of Arid Land 2017年第2期9卷 161-175页

作者： Hadi KARGAR-CHIGANI Seyed Akbar JAVADI Ghavamodin ZAHEDI-AMIRI Seyed Jamaleddin KHAJEDDIN Mohamad JAFARI department of Range management Science and Research Branch Islamic Azad University Faculty of natural resources University of Tehran Range and Watershed management Division Department of Natural Resources Isfahan University of Technology

A considerable proportion of Iran＇s territory is covered with arid and semi-arid rangelands and mismanagement and overexploitation of those rangelands have resulted in serious ecological degradation. Thus, the need is pressing to examine the present species composition and the relationships with environmental factors for providing the needed scientific references to species conservation and ecological rehabilitation efforts. The aims of this study were to examine the species composition and to delineate the most important factors influencing the distributions of plant species and groups in the northern rangelands of Isfahan Province （Iran） using two-way indicator species analysis （TWINSPAN）, detrended correspondence analysis （DCA）, principal component analysis （PCA）, and canonical correspondence analysis （CCA）. Field investigations were conducted in the growing season of 2014 using stratified random method in 22 homogeneous sampling units. In total, 75 plant species belonging to 52 genera and 19 families were identified. The most important families were Asteraceae and Papilionaceae, the most important genera were Astragalus, Cousinia, and Acanthophyllum, and the most important species were Artemisia aucheri and Artemisia sieberi. Plant species were classified into 10 groups using TWINSPAN. DCA was used to estimate the magnitude of changes in species composition along the first two ordination axes to provide gradient length estimations for PCA and CCA ordinations. The first three PCA axes and the first three CCA axes demonstrated similar cumulative percentage of variance, indicating that the environmental factors （selected by PCA） used in CCA ordination were acceptable for explaining the species composition and the distributions. CCA ordination showed that the first axis was closely related to elevation, slope, surface bare soil cover, surface litter cover, gravel proportion, organic matter, total nitrogen, CaCO3 content, and grazing intensity and that the second axi

关键词： rangeland classification ordination multivariate analysis plant groups Isfahan Province

A long way to go:impacts of urbanization on migrants’livelihoods and rural ecology in less industrialized regions

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Journal of Mountain Science 2023年第12期20卷 3450-3463页

作者： ZHANG Zhi-qi LI Ming-jing LI Wen-jun WEI Yi-ran SHI Yi-lu department of environmental management Peking UniversityBeijing 100871China

Urbanization,often coupled with industrialization,is generally considered as a boost for improving livelihood as well as alleviating ecological pressures of the rural ***,this experience needs to be tested in less industrialized areas,particularly where the urbanization is driven by non-economic factors such as urban public services and relevant government policies rather than employment *** two villages on the Qinghai-Tibet Plateau as examples,through the field investigation by using semi-structured questionnaires and in-depth interviews,and statistical data analysis,we explored the impacts of urbanization on migrants’livelihoods and the ecological conditions of their original village *** found that the disposable income and savings of emigrant households were less than the stay households,which might be correlated to the limited employment due to the lagged industrialization in the local township,and the mismatch between their traditional labor skills and the demands of urban *** home-village rangeland overuse was not alleviated since the increasing grazing pressure caused by the stay households,though the emigrant households intended to decrease the number of livestock on their home *** concluded that the urbanization misaligned with local industrialization may fail to improve migrant livelihoods and local ecological conditions in less industrialized *** research supplements the previous urbanization theory by highlighting the non-industrialization driven urbanization,and is particularly pertinent for the transitional countries worldwide.

关键词： Urbanization Industrialization Livelihoods Ecological conditions Pastoral areas Qinghai-Tibet Plateau