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Science China Chemistry 2010年第3期53卷 650-662页

作者： CHANG ChihChung CHOU C.K.Charles Andreas Wahner research center for environmental changes Academia SinicaTaipei 11529China Forschungszentrum Juelich ICG-Ⅱ:TroposphereJuelichGermany

An intensive field campaign including measurements from the environmental monitoring network and from two super sites took place in the Pearl River Delta region in summer *** routinely measured O3 and NOx concentrations,the spatial and temporal variation of O3 and of the total oxidant concentrations was *** to the spatial variability of NO2/NO,the two super sites were found to be representative of polluted urban and downwind suburban *** addition,both sites were located in high O3 ***-depth diagnostic of photochemical ozone production processes and their key controlling factors are achieved with an observation-based model(OBM) to gain regional *** analysis and sensitivity model runs show that aldehyde and HONO chemistry had significant impacts on local photochemical ozone production *** analysis of calculated Relative Incremental Reactivities shows that photochemical ozone production rates are mainly sensitive to anthropogenic hydrocarbons(HCs) in the polluted urban *** the suburban areas,sensitivity to nitrogen oxide(NO) concentrations *** anthropogenic HCs in both areas are alkenes and *** differences of ozone production efficiencies are identified between the urban and suburban regions,consistent with the OBM diagnosed results.

关键词： ozone Pearl River Delta photochemical ozone productions HONO relative incremental reactivity

Trends of Regional Precipitation and Their Control Mechanisms during 1979–2013

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Advances in Atmospheric Sciences 2016年第2期33卷 164-174页

作者： Run LIU Shaw Chen LIU Chein-Jung SHIU Jun LI Yuanhang ZHANG State Key Joint Laboratory of environmental Simulation and Pollution Control College of Environmental Sciences and Engineering Peking University research center for environmental changes Academia Sinica Department of Atmospheric Science NCU

Trends in precipitation are critical to water resources. Considerable uncertainty remains concerning the trends of regional precipitation in response to global warming and their controlling mechanisms. Here, we use an interannual difference method to derive trends of regional precipitation from GPCP （Global Precipitation Climatology Project） data and MERRA （Modern- Era Retrospective Analysis for research and Applications） reanalysis in the near-global domain of 60~ S-60~N during a major global warming period of 1979-2013. We find that trends of regional annual precipitation are primarily driven by changes in the top 30% heavy precipitation events, which in turn are controlled by changes in precipitable water in response to global warming, i.e., by thermodynamic processes. Significant drying trends are found in most parts of the U.S. and eastern Canada, the Middle East, and eastern South America, while significant increases in precipitation occur in northern Australia, southern Africa, western India and western China. In addition, as the climate warms there are extensive enhancements and expansions of the three major tropical precipitation centers-the Maritime Continent, Central America, and tropical Africa-leading to the observed widening of Hadley cells and a significant strengthening of the global hydrological cycle.

关键词： regional precipitation global warming water resources

Characterization and reactivity of biogenic manganese oxides for ciprofloxacin oxidation

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Journal of environmental Sciences 2014年第5期26卷 1154-1161页

作者： Jinjun Tu Zhendong Yang Chun Hu Jiuhui Qu State Key Laboratory of environmental Aquatic Chemistry Research Center for Eco-Environmental SciencesResearch Center for Eco-Environmental Sciences

Biogenic manganese oxides （BioMnOx） were synthesized by the oxidation of Mn（II） with Mn- oxidizing bacteria Pseudomonas sp. G7 under different initial pH values and Mn（II） dosages, and were characterized by X-ray diffraction, X-ray photoelectron spectroscopy, and UV-Vis absorption spectroscopy. The crystal structure and Mn oxidation states of BioMnOx depended on the initial pH and Mn（lI） dosages of the medium. The superoxide radical （O2） was observed in Mn-containing （III/IV） BioMnOx suspensions by electron spin resonance measurements. BioMnOx（0.4）-7, with mixed valence of Mn（II/III/IV） and the strongest O^- signals, was prepared in the initial pH 7 and Mn（II） dosage of 0.4 mmol/L condition, and exhibited the highest activity for ciproftoxacin degradation and no Mn（II） release. During the degradation of ciprofloxacin, the oxidation of the Mn（II） formed came from biotic and abiotic reactions in BioMnOx suspensions on the basis of the Mn（II） release and O2- formation from different BioMnOx. The degradation process of ciprofloxacin was shown to involve the cleavage of the hexatomic ring having a secondary amine and carbon-carbon double bond connected to a carboxyl group, producing several compounds containing amine groups as well as small organic acids.

关键词： Mn oxidation state Mn-oxidizing bacteria superoxide radicals ciprofloxacin degradation

Sex-dependent alterations in extracellular vesicles linking chronic spinal cord injury to brain neuroinflammation and neurodegeneration

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Neural Regeneration research 2025年第2期20卷 483-484页

作者： Yun Li Junfang Wu Department of Anesthesiology&Shock Trauma and Anesthesiology Research(STAR)CenterUniversity of Maryland School of MedicineBaltimoreMDUSA

Traumatic spinal cord injury(SCI)is a devastating exogenous injury with long-lasting consequences and a leading cause of death and disability *** in assistive technology,rehabilitative interventions,and the ability to identify and intervene in secondary conditions have significantly increased the long-term survival rate of SCI patients,with some people even living well into their seventh or eighth *** survival changes have led neurotrauma researchers to examine how SCI interacts with brain *** health and epidemiological data showed that patients with long-term SCI can have a lower life expectancy and quality of life,along with a higher risk of comorbidities and complications.

关键词： alterations inflammation injury

Effects of Bifidobacterium lactis BLa80 on fecal and mucosal flora and stem cell factor/c-kit signaling pathway in simulated microgravity rats

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World Journal of Gastroenterology 2025年第1期31卷 93-109页

作者： Ping Zhang Ying Zhu Pu Chen Tong Zhou Zhe-Yi Han Jun Xiao Jian-Feng Ma Wen Ma Peng Zang Ying Chen Graduate School Hebei North UniversityZhangjiakou 075000Hebei ProvinceChina Key Laboratory of Aerospace Nutrition and Food Engineering China Astronaut Research and Training CenterBeijing 100094China Department of Gastroenterology The Air Force Medical CenterBeijing 100142China Department of Blood Transfusion Air Force Medical CenterBeijing 100142China

BACKGROUND Simulated microgravity environment can lead to gastrointestinal motility *** pathogenesis of gastrointestinal motility disorders is closely related to the stem cell factor(SCF)/c-kit signaling pathway associated with intestinal flora and Cajal stromal ***,intestinal flora can also affect the regulation of SCF/c-kit signaling pathway,thus affecting the expression of Cajal stromal *** cells are the pacemakers of gastrointestinal *** To investigate the effects of Bifidobacterium lactis(***)BLa80 on the intestinal flora of rats in simulated microgravity and on the gastrointestinal motility-related SCF/c-kit *** The internationally recognized tail suspension animal model was used to simulate the microgravity environment,and 30 rats were randomly divided into control group,tail suspension group and drug administration tail suspension group with 10 rats in each group for a total of 28 *** tail group was given *** BLa80 by intragastric administration,and the other two groups were given water intragastric administration,the concentration of intragastric administration was 0.1 g/mL,and each rat was 1 mL/***&eosin staining was used to observe the histopathological changes in each segment of the intestine of each group,and the expression levels of SCF,c-kit,extracellular signal-regulated kinase(ERK)and p-ERK in the gastric antrum of each group were detected by Western blotting and *** fecal flora and mucosal flora of rats in each group were detected by 16S *** Simulated microgravity resulted in severe exfoliation of villi of duodenum,jejunum and ileum in rats,marked damage,increased space between villi,loose arrangement,shortened columnar epithelium of colon,less folds,narrower mucosal thickness,reduced goblet cell number and crypts,and significant improvement after probiotic *** microgravity reduced the expressions of SCF and c-kit,and increased the express

关键词： Simulated microgravity Rat Intestinal flora Gastrointestinal motility Stem cell factor/c-kit signaling pathway

A Closure Study of Aerosol Hygroscopic Growth Factor during the 2006 Pearl River Delta Campaign

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Advances in Atmospheric Sciences 2010年第4期27卷 947-956页

作者：刘新罡张远航温梦婷王京丽 Jinsang JUNG 张士煜胡敏曾立民 Young Joon KIM College of environmental Sciences and Engineering Peking University Institute for Urban Meteorology China Meteorological Administration Department of environmental Science and Engineering Gwangju Institute of Science and Technology Gwangju Korea research center for environmental changes Academia Sinica

Measurements of aerosol physical, chemical and optical parameters were carried out in Guangzhou, China from 1 July to 31 July 2006 during the Pearl River Delta Campaign. The dry aerosol scattering coefficient was measured using an integrating nephelometer and the aerosol scattering coefficient for wet conditions was determined by subtracting the sum of the aerosol absorption coefficient, gas scattering coefficient and gas absorption coefficient from the atmospheric extinction coefficient. Following this, the aerosol hygroscopic growth factor, f（RH）, was calculated as the ratio of wet and dry aerosol scattering coefficients. Measurements of size-resolved chemical composition, relative humidity （RH）, and published functional relationships between particle chemical composition and water uptake were likewise used to find the aerosol scattering coe？cients in wet and dry conditions using Mie theory for internally- or externally-mixed particle species [（NH_4）_2SO_4, NH_4NO_3, NaCl, POM, EC and residue]. Closure was obtained by comparing the measured f（RH） values from the nephelometer and other in situ optical instruments with those computed from chemical composition and thermodynamics. Results show that the model can represent the observed f（RH） and is appropriate for use as a component in other higher-order models.

关键词： atmospheric aerosol hygroscopic growth factor closure experiment Pearl River Delta campaign

Uncertainty analyses on the calculation of water environmental capacity by an innovative holistic method and its application to the Dongjiang River

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Journal of environmental Sciences 2014年第9期26卷 1783-1790页

作者： Qiuwen Chen Qibin Wang Zhijie Li Ruonan Li center for Eco-environmental research Nanjing Hydraulic Research Institute State Key Laboratory of environmental Aquatic Chemistry Research Center for Eco-Environmental SciencesChinese Academy of sciences

The estimation and allocation of water environmental capacity （WEC） are essential to water quality management and social-economic interests. However, there is inevitable uncertainty in the capacity estimation due to model conceptualization, data collection and parameter calibration. An innovative holistic approach was developed, which took both independence and relevance between parameters into account to analyze the uncertainties in WEC calculation and estimate the margin of safety. The Doniang River was taken as the case to demonstrate the method, focusing on the chemical oxygen demand and NH-N that were the two major water quality problems in the river. The results showed that the proposed holistic approach is very promising and applicable compared to traditional methods of uncertainty analysis.

关键词： Water environmental capacityModel uncertaintyHolistic approachDon^iang River

Simultaneous denitrification and denitrifying phosphorus removal in a full-scale anoxic–oxic process without internal recycle treating low strength wastewater

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Journal of environmental Sciences 2016年第1期28卷 175-183页

作者： Qibin Wang Qiuwen Chen State Key Laboratory of environmental Aquatic Chemistry Research Center for Eco-Environmental Sciences Chinese Academy of Sciences center for Eco-environmental research Nanjing Hydraulic Research Institute

Performance of a full-scale anoxic-oxic activated sludge treatment plant（4.0×10-5 m-3/day for the first-stage project） was followed during a *** plant performed well for the removal of carbon,nitrogen and phosphorus in the process of treating domestic wastewater within a temperature range of 10.8℃ to 30.5℃.Mass balance calculations indicated that COD utilization mainly occurred in the anoxic phase,accounting for 88.2% of total COD *** nitrogen removal occurred 13.71% in the anoxic zones and 78.77% in the aerobic *** contribution of anoxic zones to total nitrogen（TN） removal was 57.41%.Results indicated that nitrogen elimination in the oxic tanks was mainly contributed by simultaneous nitrification and denitrification（SND）.The reduction of phosphorus mainly took place in the oxic zones,51.45% of the total *** phosphorus removal was achieved biologically by 11.29%.Practical experience proved that adaptability to gradually changing temperature of the microbial populations was important to maintain the plant overall *** changes in temperature did not cause paralysis of the system just lower removal efficiency,which could be explained by functional redundancy of microorganisms that may compensate the adverse effects of temperature changes to a certain ***-oxic process without internal recycling has great potential to treat low strength wastewater（i.e.,TN 〈 35 mg/L） as well as reducing operation costs.

关键词： Wastewater treatment Biological nutrient removal Simultaneous nitrification and denitrification Denitrifying phosphorus removal

Review on water leakage control in distribution networks and the associated environmental benefits

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Journal of environmental Sciences 2014年第5期26卷 955-961页

作者： Qiang Xu Ruiping Liu Qiuwen Chen Ruonan Li research center for Eco-environmental Sciences Chinese Academy of Sciences center for Eco-environmental research Nanjing Hydraulics Research Institute China Three Gorges University

Water supply is the primary element of an urban system. Due to rapid urbanization and water scarcity, maintaining a stable and safe water supply has become a challenge to many cities, whereas a large amount of water is lost from the pipes of distribution systems. Water leakage is not only a waste of water resources, but also incurs great socio-economic costs. This article presents a comprehensive review on the potential water leakage control approaches and specifically discusses the benefits of each to environmental conservation. It is concluded that water leakage could be further reduced by improving leakage detection capability through a combination of predictive modeling and monitoring instruments, optimizing pipe maintenance strategy, and developing an instant pressure regulation system. The environment could benefit from these actions because of water savings and the reduction of energy consumption as well as greenhouse gas emissions.

关键词： water leakage control water distribution system environmental benefits

Monitoring of non-point source pollutants load from a mixed forest land use

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Journal of environmental Sciences 2010年第6期22卷 801-805页

作者： Sung Wan Yoon Se Woong Chung Dong Geun Oh Jae Woon Lee Department of environmental Engineering Chungbuk National University Geum River environmental research center National Institute of Environmental Research

The aim of this study was to determine the unit load of NPS （non-point source） pollutants including organic variables such as BOD （biochemical oxygen demand）, COD （chemical oxygen demand） and DOC （dissolved organic carbon）, nitrogen and phosphorus constituents, and suspended solids （SS） and their event mean concentration （EMC） of runoff flows from a water-shed of mixed forest land use by intensive field experiments. Field monitoring for continuous measurements of rainfall, flow, and water quality was conducted over 12 storm events during 2008-2009 using automated and manual sampling methods. The EMCs of individual runoff event were estimated for each water quality constituent based on the flow rate and concentration data of runoff discharge. The average EMCs of BOD, COD, DOC, SS, TN （total nitrogen）, NH4^＋-N, NO3^--N, TP （total phosphorus）, PO4^3-P from the mixed forest land were 1.794, 3.498, 1.462, 10.269, 0.862, 0.044, 0.634, 0.034, and 0.005 mg/L, respectively. The annual unit loads of BOD, COD, DOC, SS, TN, NH4^＋-N, NO3^--N, TP and PO4^3--P were estimated as 66.9, 133.2, 55.5, 429.8, 36.5, 1.6, 26.9, 1.3 and 0.1 kg/（ha·yr）, respectively. In addition, affecting parameters on the EMCs were investigated by statistic analysis of the field data. As a result, significant correlations with precipitation, rainfall intensity, and total runoff flows were found in most constituents.

关键词： event mean concentration mixed forest land use non-point source pollutant load unit load