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Journal of environmental Sciences 2022年第11期34卷 122-135页

作者： Yuye Luo Cheng Liu Congcong Li Yiwen Shan Tariq Mehmood Key Laboratory of Integrated Regulation and resource Development on Shallow Lake of Ministry of Education College of EnvironmentHohai UniversityNanjing 210098China college of environment Hohai UniversityNanjing 210098China

Dissolved organic nitrogen(DON) has attracted much attention in drinking water treatment due to its potential to produce nitrogenous disinfection by-products(N-DBPs). This work was designed to explore the transformation and fate of DON and dissolved inorganic nitrogen(DIN) in drinking water treatment. The changes of DON and formation of N-DBPs were evaluated along the water treatment route(i.e., pre-ozonation and biologicalcontact oxidation, delivery pipes’ transportation, coagulation-sedimentation, sand filtration, post-ozonation, biological activated carbon, ultrafiltration and disinfection) of drinking water treatment plant(DWTP). The transformation mechanism of DON was comprehensively investigated by molecular weight fractionation, three-dimensional fluorescence, LCOCD(Liquid Chromatography-Organic Carbon Detection), total free amino acids. A detailed comparison was made between concentrations and variations of DON and DIN affected by seasons in the drinking water treatment. Regardless of seasonal variation in raw water concentration, the DON removal trends between different treatment processes remain constant in the present study. Compared to other treatment processes, pre-ozonation and coagulation-sedimentation exhibited the dominant DON removal in different seasons, i.e.,11.13%-14.45% and 14.98%-22.49%, respectively. Contrary, biological-contact oxidation and biological activated carbon negatively impacted the DON removal, in which DON increased by 1.76%-6.49% in biological activated carbon. This may be due to the release of soluble microbial products(SMPs) from bacterial metabolism, which was further validated by the rise of biopolymers in LC-OCD.

关键词： Dissolved organic nitrogen Nitrogenous disinfection byproducts Drinking water treatment Soluble microbial products

Abnormal energy metabolism and tau phosphorylation in the brains of middle-aged mice in response to atmospheric PM2.5 exposure

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Journal of environmental Sciences 2017年第12期29卷 145-153页

作者： Rui Gao Tingting Ku Xiaotong Ji Yingying Zhang Guangke Li Nan Sang college of environment and resource Research Center of Environment and HealthShanxi UniversityTaiyuan 030006China

In light of the accelerated aging of the global population and the deterioration of the atmosphere pollution, we sought to clarify the potential mechanisms by which fine particulate matter（PM_（2.5）） can cause cognitive impairment and neurodegeneration through the alteration of mitochondrial structure and function. The results indicate that PM_（2.5） inhalation reduces ATP production by disrupting the aerobic tricarboxylic acid cycle and oxidative phosphorylation, thereby causing the hypophosphorylation of tau in the cortices of middle-aged mice. Furthermore, excessive reactive oxygen species generation was involved in the impairment. Interestingly, these alterations were partially reversed after exposure to PM_（2.5） ended. These findings clarify the mechanism involved in mitochondrial abnormality-related neuropathological dysfunction in response to atmospheric PM_（2.5） inhalation and provide an optimistic sight for alleviating the adverse health outcomes in polluted areas.

关键词： Fine particulate matter（PM_（2.5）） Mitochondrial structure and function Energy metabolism Reactive oxygen species（ROS） Tau phosphorylation

Evidence of Glacial Erratic Rollover Revealed by ^(10)Be and ^(26)Al Concentration Variations

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Acta Geologica Sinica(English Edition) 2022年第1期96卷 369-375页

作者： ZHANG Zhigang WANG Jian XU Xiaobin CHANG Zhiyang CUI Haitao LIANG Zhong CHEN Xia SHANG Zhiyuan School of Geography Nanjing Normal UniversityNanjing 210023China Key Laboratory of Virtual Geographic environment(Nanjing Normal University) Ministry of EducationNanjing 210023China State Key Laboratory Cultivation Base of Geographical environment Evolution(Jiangsu Province) Nanjing 210023China Jiangsu Center for Collaborative Innovation in Geographical Information resource Development and Application Nanjing 210023China Jiangsu Second Normal University Nanjing 210013China tourism and Social Administration college Nanjing Xiaozhuang UniversityNangjing 211171China

Cosmogenic nuclide exposure dating is one of the most intensively applied dating methods with which to study glacial geomorphology.Glacial erratics have been the major dating objective in many studies.Some research has proposed that glacial erratics may undergo rollover and re-transportation during the late exposure stage,which can affect the dating results.However,there is no direct evidence to confirm this possibility.In this study,we collected seven samples from a vertical section inside a glacial erratic in the paleo-Daocheng ice cap in the southeastern Tibetan Plateau,measuring their contents of the cosmogenic nuclides ^(10)Be and ^(26)Al.The results show that from the top to the bottom,the concentrations of 10Be were(1.21±0.05)×10^(6),(1.00±0.02)×10^(6),(0.88±0.03)×10^(6),(0.77±0.02)×10^(6),(0.75±0.03)×10^(6),(0.95±0.03)×10^(6) and(1.46±0.04)×10^(6) atoms/g.The ^(10)Be concentrations decreased from(1.21±0.05)×10^(6) atoms/g to(0.75±0.03)×10^(6) atoms/g and then increased to(1.46±0.04)×10^(6) atoms/g,which is not consistent with the theoretical prediction of a gradual decrease.This phenomenon indicates that the glacial erratic may have rolled over at least once.The lower surface of the erratic could have been on top at some time in the past.Therefore,its exposure age was greater than the exposure age that was expected,based on its current orientation.This study provides numerical evidence for an erratic rollover event.

关键词： glacial erratics ^(10)Be and^(26)Al rollover Tibetan Plateau

Evaluation of tourism Development Potential in Kubuqi Desert

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Evaluation of Tourism Development Potential in Kubuqi Desert

Spatiotemporal changes in vegetation coverage and its driving factors in the Three-River Headwaters Region during 2000-2011

作者： Jin ZHU Zhibao DONG Li CHENG Nan XIAO School of Geographic Science and tourism Shaanxi Normal University college of resources and environment Baotou Teachers College

From the four aspects namely the tourist resources,regional traffic conditions,tourism service ability,social economic foundation,we choose 13 factors to establish desert tourism development potential evaluation index system,using the analytic hierarchy process（AHP） to determine the index weight,using multi-objective linear weighting function method to evaluate the tourism development potential of desert region,aims to provide reference for tourism development in the region and provide reference for tourism resources development.The results show that:The quality,abundance,road accessibility,hotel reception capacity and location of tourism resources are the main factors that affect the tourism development in Kubuqi Desert;At present,the desert tourism development potential of Dalad Banner is better than Hangjin Banner and Junger Banner;The desert tourism development of the three places has the condition of similar projects,not obvious characteristics,and they three compete with each other but could not develop co-operatively.

关键词： desert tourism potential evaluation Kubuqi

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Journal of Geographical Sciences 2014年第2期24卷 288-302页

作者： LIU Xianfeng ZHANG Jinshui ZHU Xiufang PAN Yaozhong LIU Yanxu ZHANG Donghai LIN Zhihui State Key Laboratory of Earth Surface Processes and resource Ecology Beijing Normal University Beijing 100875 China college of resources Science & Technology Beijing Normal University Beijing 100875 China college of Urban and environmental Sciences Peking University Beijing 100871 China college of tourism and environment Shaanxi Normal University Xi'an 710062 China

The Three-River Headwaters Region （TRHR）, which is the source area of the Yangtze River, Yellow River, and Lancang River, is of key importance to the ecological secu- rity of China. Because of climate changes and human activities, ecological degradation oc- curred in this region. Therefore, ＂The nature reserve of Three-River Sou,＇ce Regions＂ was established, and ＂The project of ecological protection and construction for the Three-River Headwaters Nature Reserve＂ was implemented by the Chinese government. This study, based on MODIS-NDVI and climate data, aims to analyze the spatiotemporal changes in vegetation coverage and its driving factors in the TRHR between 2000 and 2011, from three dimensions. Linear regression, Hurst index analysis, and partial correlation analysis were employed. The results showed the following：（1） In the past 12 years （2000-2011）, the NDVI of the study area increased, with a linear tendency being 1.2%/10a, of which the Yangtze and Yellow River source regions presented an increasing trend, while the Lancang River source region showed a decreasing trend. （2） Vegetation coverage presented an obvious spatial difference in the TRHR, and the NDVI frequency was featured by a bimodal structure. （3） The area with improved vegetation coverage was larger than the degraded area, being 64.06% and 35.94%, respectively during the study period, and presented an increasing trend in the north and a decreasing trend in the south. （4） The reverse characteristics of vegetation cov- erage change are significant. In the future, degradation trends will be mainly found in the Yangtze River Basin and to the north of the Yellow River, while areas with improving trends are mainly distributed in the Lancang River Basin. （5） The response of vegetation coverage to precipitation and potential evapotranspiration has a time lag, while there is no such lag in the case of temperature. （6） The increased vegetation coverage is mainly attributed to the warm-wet climate change and the implementation of the ecological protectio

关键词： vegetation coverage spatiotemporal change future trend influence factors Three-River HeadwatersRegion

Diffuse pollution from livestock production in China

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Chinese Journal Of Geochemistry 2005年第2期24卷 189-193页

作者：王晓燕 college of resource Environment & Tourism Capital Normal University Beijing 100037 China Key Lab. of 3D Information Acquisition and Application MOE Beijing 100037 China

With economic development and living standard improvement, livestock and poultry production has grown up rapidly, also has become the leading source of pollution in vast rural areas in China. The estimated annual loss amount of COD, BOD, NH-3-N from manure in 2001 is {7.28} million ton, {4.99} million ton and {1.32} million ton, respectively. The COD loss amount from manure is close to the sum of COD from industrial and domestic wastewater. Because animal waste and wastewater can enter water bodies from spills or breaks of waste storage structures (due to accidents or excessive rain), and non-agricultural application of manure to cropland, this contamination has resulted in quality degradation of surface and underground drinking water supplies. Areas with concentrated livestock operations are showing elevated nutrients and organic pollutant contents in surface waters. This widespread contamination of water has prompted governments at various levels to adopt regulations and measures to control the spreading of livestock pollution.

关键词：污染扩散中国牲畜排泄物 COD BOD 工业废水

Combining environmental Factors and Lab VNIR Spectral Data to Predict SOM by Geospatial Techniques

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Chinese Geographical Science 2019年第2期29卷 258-269页

作者： GUO Long ZHANG Haitao CHEN Yiyun QIAN Jing college of resources and environment Huazhong Agricultural University School of resource and environment Wuhan University

Soil organic matter(SOM) is an important parameter related to soil nutrient and miscellaneous ecosystem services. This paper attempts to improve the performance of traditional partial least square regression(PLSR) model by considering the spatial autocorrelation and soil forming factors. Surface soil samples(n = 180) were collected from Honghu City located in the middle of Jianghan Plain, China. The visible and near infrared(VNIR) spectra and six environmental factors(elevation, land use types, roughness, relief amplitude, enhanced vegetation index, and land surface water index) were used as the auxiliary variables to construct the multiple linear regression(MLR), PLSR and geographically weighted regression(GWR) models. Results showed that: 1) the VNIR spectra can increase about 39.62% prediction accuracy than the environmental factors in predicting SOM; 2) the comprehensive variables of VNIR spectra and the environmental factors can improve about 5.78% and 44.90% relative to soil spectral models and soil environmental models, respectively; 3) the spatial model(GWR) can improve about 3.28% accuracy than MLR and PLSR. Our results suggest that the combination of spectral reflectance and the environmental variables can be used as the suitable auxiliary variables in predicting SOM, and GWR is a promising model for predicting soil properties.

关键词： visible near infrared spectral reflectance environmental factors spatial characteristics partial least squares regression geographically weighted regression

Simulation study on ultrasonic tomography for grouted reinforced concrete by finite element

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Journal of Central South University 2015年第7期22卷 2791-2799页

作者：朱自强喻波李亚楠肖嘉莹周勇 School of Geosciences and Info-Physics Engineering Central South University Hunan Chaji Expressway Construction and Development Co. Ltd. college of resource and environment and tourism Hunan University of Arts and Science

A finite element reconstruction algorithm for ultrasound tomography based on the Helmholtz equation in frequency domain is presented to monitor the grouting defects in reinforced concrete structures.In this algorithm,a hybrid regularizations-based iterative Newton method is implemented to provide stable inverse solutions.Furthermore,a dual mesh scheme and an adjoint method are adopted to reduce the computation cost and improve the efficiency of reconstruction.Simultaneous reconstruction of both acoustic velocity and attenuation coefficient for a reinforced concrete model is achieved with multiple frequency data.The algorithm is evaluated with numerical simulation under various practical scenarios including varied transmission/receiving modes,different noise levels,different source/detector numbers,and different contrast levels between the heterogeneity and background region.Results obtained suggest that the algorithm is insensitive to noise,and the reconstructions are quantitatively accurate in terms of the location,size and acoustic properties of the target over a range of contrast levels.

关键词：钢筋混凝土结构超声波成像仿真有限元重建算法层析锚固亥姆霍兹方程

Dominant bacteria correlated with elimination of sludge in an innovative reactor

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Progress in Natural Science:Materials International 2009年第12期19卷 1765-1771页

作者： Shanshan Lin~a,Ying Wang~a,Jifang Lin~a,Xinrui Wang~b,Huili Gong~(c,*) a School of Urban and environmental Science,Northeast Normal University,Changchun 130024,China b college of Medicine,Jilin University,Changchun 130064,China c School of resource environment and tourism,Capital Normal University,Beijing 100048,China School of Urban and environmental Science Northeast Normal University Changchun 130024 China college of Medicine Jilin University Changchun 130064 China School of resource environment and tourism Capital Normal University Beijing 100048 China

This study was conducted to identify bacteria responsible for the elimination of sludge in an innovative gravel contact oxidation reactor (GCOR) and a conventional activated sludge reactor(ASR).Fluorescent in situ hybridization revealed thatα-,β-,γ- andε-Proteobacteria and Bacteroidetes were present in both reactors.In the GCOR,γ-Proteobacteria accounted for 13%of the biofilm biomass on the carrier,whileα-,ε- andβ-Proteobacteria accounted for 12%.However,the predominant bacteria in the pores of the carrier in the GCOR were Bacteroidetes(18%),ε-Proteobacteria(13%),β- andα-Proteobacteria(10%) andγ-Proteobacteria(9%).Conversely,β-Proteobacteria(18%),Bacteroidetes(13%),α- andγ-Proteobacteria(12%) andε-Proteobacteria(5%) dominated the sediment community of the ASR.

关键词： Predominant bacteria Gravel contact oxidation reactor(GCOR) Excess sludge elimination Fluorescent in situ hybridization(FISH)