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Opportunities of Advanced Physical Studies at the Hefei Advanced Light Facility
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作者 孙喆 封东来 《Chinese Physics Letters》 SCIE EI CAS CSCD 2024年第3期127-130,共4页
Synchrotron radiation has transformed the role of xrays as a mainstream tool for probing the atomic and electronic structure of materials.Synchrotron-based xray sciences have been widely used to study the microscopic ... Synchrotron radiation has transformed the role of xrays as a mainstream tool for probing the atomic and electronic structure of materials.Synchrotron-based xray sciences have been widely used to study the microscopic structure,electronic states,chemical composition. 展开更多
关键词 materials transformed structure
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Plant Diversity in City Parks under the Concept of Landscaping:A Case Study of Hefei City
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作者 GAO Miaomiao LI Yinan CHEN Jiaxin 《Journal of Landscape Research》 2023年第4期73-78,共6页
Driven by the concept of landscaping,this paper analyzed the impact of plant diversity on landscaping function,arrangement methods and community structure by taking plot sampling method as the experimental axis and 3 ... Driven by the concept of landscaping,this paper analyzed the impact of plant diversity on landscaping function,arrangement methods and community structure by taking plot sampling method as the experimental axis and 3 urban parks in Hefei as the blueprint.Six plots with the size of 20 m×20 m were selected for investigation.There were 56 species of plants belonging to 50 genera and 42 families in the plots of Zhongshan Road City Park,48 species of plants belonging to 44 genera and 40 families in the plots of Four Seasons Flower Sea City Park,and 69 species of plants belonging to 57 genera and 45 families in the plots of Xiaoyaojin Park.The survey results show that there are following problems in city parks:lack of plant effectiveness,too homogeneous plant community,disharmony between landscape and environment,poor plant maintenance and lack of attention to ecological maintenance.Based on this,the optimization measures are put forward:increasing evergreen plants to avoid no scenery in autumn,developing plants with excellent landscape effects and a variety of colorful plants,paying attention to the shaping of spatial structure and landscape pattern,regularly taking care of plants and their surrounding environment.It is expected to provide some reference for the construction and development of Hefei city parks,ensure the healthy and stable development of city parks,and provide ideas and methods for the improvement of plant landscaping in city parks. 展开更多
关键词 Landscaping concept City park Plant diversity
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Influence of Urban Street Greening Design under the Concept of Green Healthy Cities:A Case Study of Hefei City
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作者 HUANG Jin 《Journal of Landscape Research》 2023年第4期31-34,40,共5页
In order to explore the influence of urban street greening,the street landscape of Changjiang West Road and Xiyou Road in Hefei City was selected as the research sample to study the design of urban street landscape un... In order to explore the influence of urban street greening,the street landscape of Changjiang West Road and Xiyou Road in Hefei City was selected as the research sample to study the design of urban street landscape under the concept of green healthy cities.The results show that the urban street landscape of Hefei City is single in design and plant type,and plant maintenance management is not good.It is proposed to strengthen the maintenance and management of street greening,increase the types of native plants,and improve cultural connotation,so as to enhance the artistry,regionalism and functionality of urban street landscape in Hefei City. 展开更多
关键词 Green healthy cities Urban landscape design Street landscape design
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Transformation Design of Old Parks Based on Behavior Psychology: A Case Study of Hefei Xiaoyaojin Park
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作者 GE Juan CAO Menghan +3 位作者 CHEN Jiaxin HU Yueyue LI Quanjun LI Yinan 《Journal of Landscape Research》 2023年第5期35-40,共6页
City park undertakes the function of urban core green island. Hefei Xiaoyaojin Park providesa leisure and entertainment place for Hefei citizens. Although it has been continuously transformed andupgraded, there are st... City park undertakes the function of urban core green island. Hefei Xiaoyaojin Park providesa leisure and entertainment place for Hefei citizens. Although it has been continuously transformed andupgraded, there are still many places to be improved. Through behavior observation and questionnaire,the usage and satisfaction evaluation of tourists in Xiaoyaojin Park were obtained, and the transformationdesign of Xiaoyaojin Park was analyzed from the perspective of behavior psychology by analyzing thebehavior of tourists in different zones of Xiaoyaojin. Based on the premise of exploring the behaviorof tourists in different spaces, a city park environment that meets the needs of tourists can be created bypromoting the cultural context of the Three Kingdoms, improving the plant landscape and infrastructureof the site, optimizing the spatial function, and exploring the park design and transformation strategy that ismore in line with the needs of people, in order to provide new ideas for the future landscape transformationof Xiaoyaojin park, and offer reference suggestions for the future transformation design of old city parks. 展开更多
关键词 Behavior psychology Old park City park Environmental optimization
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Urban Waterfront Space Design under the Concept of Ecological Conservation:A Case Study of Hefei Swan Lake
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作者 LI Quanjun GE Juan +1 位作者 WANG Mengqing HU Yueyue 《Journal of Landscape Research》 2023年第4期45-49,共5页
With the proposal of the concept that lucid waters and lush mountains are invaluable assets,ecological issues have become increasingly important issues of concern to people.The process of urbanization is accelerating,... With the proposal of the concept that lucid waters and lush mountains are invaluable assets,ecological issues have become increasingly important issues of concern to people.The process of urbanization is accelerating,and the importance of urban waterfront space in improving the environmental quality of the city and people’s quality of life,enhancing the vitality of the city,the overall appearance of the city,and the competitiveness of the city,is receiving increasing attention.And how to properly handle the construction and development of urban waterfront space has become increasingly prominent in urban planning.Under the the concept of“ecological conservation”,it is thought that the construction of urban waterfront space should follow the principle of harmony between nature and man,and strengthen the multifaceted connection of the city.Through field research on Swan Lake,a comprehensive evaluation of the problems in the plank road and land ecology is conducted.It is proposed to improve the current situation of Swan Lake by grasping the two keywords of“waterfront”and“city”,and starting from the improvement of water body and the enhancement of urban cultural construction in the lake area. 展开更多
关键词 Ecological conservation Urban environmental improvement Waterfront space
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Policy Needs for Social Security in the Process of Citizenization of the Peri-urban Farmers:A Case Study of Hefei City
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作者 TAN Jiang-lin CHEN Rui NI Wen-cong 《Asian Agricultural Research》 2012年第12期66-70,75,共6页
We conduct a survey of transformational towns and villages in High-tech Development District, Yaohai District and Shushan District, Hefei City. Using data, we analyze the "sideline effect" and inherent contr... We conduct a survey of transformational towns and villages in High-tech Development District, Yaohai District and Shushan District, Hefei City. Using data, we analyze the "sideline effect" and inherent contradiction of transformational cities, research the policy needs for social security and its trend in the citizenization process of the peri-urban farmers. On this basis, we construct the social security policy system that can adapt to the accelerated process of urbanization. Finally, we put forth the following recommendations for the social security policy in the citizenization process of the peri-urban farmers: distinguishing different groups' policy needs for social security; attaching importance to people's dynamic policy needs for social security in urbanization; focusing on the adaptability of social security policy transformation in urbanization; attaching importance to the social psychosocial environment of social security policy transformation in urbanization; achieving the trinity of non-farm conversion, urbanization and citizenization in the process of urbanization; strengthening the government's dominant position in the building of social security policy system. 展开更多
关键词 Hefei CITY PERI-URBAN FARMERS CITIZENIZATION Socia
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A multi-scale 3-D crust velocity model in the Hefei-Chao Lake area around the southern segment of Tanlu Fault Zone
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作者 Lingli Li Huajian Yao +4 位作者 Song Luo Junhui Li Xiaoli Wang Hongyu Ni Ziwen Bao 《Earthquake Science》 2021年第4期344-357,共14页
Regional high-precision velocity models of the crust are an important foundation for examining seismic activity,seismogenic environments,and disaster distribution characteristics.The Hefei-Chao Lake area contains the ... Regional high-precision velocity models of the crust are an important foundation for examining seismic activity,seismogenic environments,and disaster distribution characteristics.The Hefei-Chao Lake area contains the main geological units of Hefei Basin,with thick sediments and the Chao Lake depression.Several major concealed faults of the southern NNE-trending Tanlu Fault Zone cross this area.To further explore the underground distribution characteristics of the faults and their tectonic evolutionary relationship with adjacent tectonic units,this study used ambient noise data recorded by a seismic array deployed in Hefei City and Chao Lake,constructing a 3-D velocity model at the depth of 1–8 km.Then a multi-scale high-resolution 3-D velocity model of this area was constructed by this new upper crustal velocity model with the previous middle and lower crustal model.The new model reveals that a high-velocity belt is highly consistent with the strike of the Tanlu Fault Zone,and a low-velocity sedimentary characteristic is consistent with the Hefei Basin and Chao Lake depression.The distribution morphology of high and low velocity bodies shows that the sedimentary pattern of Hefei-Chao Lake area is closely related to the tectonic evolution of the Tanlu Fault Zone since the Mesozoic.This study also identifies multiple low-velocity anomalies in the southeastern Hefei City.We speculate that strong ground motion during the 2009 Feidong earthquake(magnitude of 3.5)was related to amplification by the thick sediments in the Hefei Basin.We also discuss further applications of multi-scale high-resolution models of the shallow layer to strong ground motion simulations in cities and for earthquake disaster assessments. 展开更多
关键词 Tanlu Fault Zone Hefei-Chao Lake area CRUST multi-scale velocity model
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Urban Construction Land Suitability Evaluation Based on Improved Multi-criteria Evaluation Based on GIS(MCE-GIS): Case of New Hefei City,China 被引量:18
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作者 ZHANG Xiaorui FANG Chuanglin +1 位作者 WANG Zhenbo MA Haitao 《Chinese Geographical Science》 SCIE CSCD 2013年第6期740-753,共14页
Urban construction land suitability evaluation(UCLSE)is a complex system engineering and the basis for rational use of the limited urban land resources in China.It has an important practical value on urban constructio... Urban construction land suitability evaluation(UCLSE)is a complex system engineering and the basis for rational use of the limited urban land resources in China.It has an important practical value on urban construction land use planning and management from the angle of methodology.As a widely used technique,traditional multi-criteria evaluation based on GIS(MCE-GIS),is not suitable for UCLSE.This study develops an improved MCE-GIS method which could be more suitable for UCLSE based on urban complex ecological system theory and the summary of the shortcomings of traditional MCE-GIS.The improvements include three aspects:a composite evaluation index system rather than natural indexes alone,an index weight calculated by using fuzzy Analytic Hierarchy Process(AHP)method rather than the common AHP method,and the integrated overlay rule,which includes selecting the minimum value,weighted linear combination(WLC)and simple summation.The main advantage of this improved technique is that it can make UCLSE more comprehensive,more operational and more reasonable.It can provide a scientific basis for decision making in the planning and management of urban construction land use.The improved MCE-GIS system has been adopted in the New Hefei City,Anhui Province,China.Based on the results of UCLSE in New Hefei,three functional areas including construction-appropriate areas,construction-restricted areas and construction-forbidden areas could be worked out,in which 36.90%of the total study area could be developed as urban construction land and the remaining 63.10%should be protected as reserves land or as ecological land.Furthermore,the results can provide scientific decision support for spatial planning and eco-environment protection in New Hefei. 展开更多
关键词 城市建设用地 GIS系统 适宜性评价 标准评价 合肥市 中国 模糊层次分析法 综合评价指标体系
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Rh-incompatible hemolytic disease of the newborn in Hefei 被引量:7
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作者 Shao-Hua Bi Liang-Liang Jiang +11 位作者 Li-Ying Dai Hong Zheng Jian Zhang Li-Li Wang Chao Wang Qiao Jiang Yu Liu Yong-Li Zhang Juan Wang Chao Zhu Guang-Hui Liu Ru-Jeng Teng 《World Journal of Clinical Cases》 SCIE 2019年第20期3202-3207,共6页
BACKGROUND Anti-D antibody is not the common cause of Rh-isoimmunization in Chinese neonatal jaundice.Recent change in national population policy has followed by an increase in Rh-isoimmunization related hemolytic dis... BACKGROUND Anti-D antibody is not the common cause of Rh-isoimmunization in Chinese neonatal jaundice.Recent change in national population policy has followed by an increase in Rh-isoimmunization related hemolytic disease of the newborn(HDN).Unfortunately,regional status of Rh-HDN is unavailable.We hypothesize that Rh-HDN in our region is most commonly due to anti-E antibody.AIM To investigate the prevalence of hemolytic disease of the newborn due to Rhisoimmunization in Hefei City.METHODS Retrospective review of data obtained from Children’s Hospital of Anhui and Hefei Blood Center between January 2017 and June 2019.Status of minor blood group antibody was studied in the corresponding mothers.RESULTS Totally 4138 newborns with HDN admitted during the study period and 116(2.8%)received blood exchange transfusion(BET).Eighteen newborns(0.43%)with proven Rh-incompatible HDN were identified.All were not the first-born baby.Thirteen mothers were RhD(+)(72%)and five were RhD(-).The distribution of Rh-related antibodies in mothers was ten anti-E(55%),five anti-D(27%),and for one anti-C,anti-c,and anti-E/c(6%)each.Thirteen(72.2%)were qualified for BET,relative risk for BET was 28.9 as compared to other types of HDN,but only 10 received due to parenteral refusal.All(100%)RhD related HDN received BET which is not significantly different from RhE related HDN(81.8%).CONCLUSION As expected,all Rh-incompatible HDN newborns were not the first-born.Contrary to the Caucasian population,anti-D induced HDN is not the most common etiology.In our region,anti-E(11/18,61%)is the most common cause of Rh-HDN. 展开更多
关键词 Rh-isoimmunization HEMOLYTIC disease of the NEWBORN MINOR BLOOD group
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Development and application of the new BPM system data processing program at Hefei light source 被引量:3
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作者 MA Tianji YANG Yongliang SUN Baogen ZOU Junying LU Ping ZHOU Zeran XU Hongliang 《Nuclear Science and Techniques》 SCIE CAS CSCD 2012年第5期261-266,共6页
A data processing program has been applied for the new beam position monitor (BPM) system of the storage ring at Hefei Light Source (HLS). The new BPM system in the upgrade project will be equipped with Libera Brillia... A data processing program has been applied for the new beam position monitor (BPM) system of the storage ring at Hefei Light Source (HLS). The new BPM system in the upgrade project will be equipped with Libera Brilliance BPM processors to replace the old Bergoz MX-BPM processors. The embedded Linux system on Libera has completed some important work, including instrument status check,data acquisition, position calculation, EPICS IOC data release,and so on. A new EPICS record type has been developed to recalculate the beam position with log-ratio method. The property of the new position data was analyzed in the time and frequency domain. The results show that the rms value of beam position measurement resolution can be up to submicron. Preliminary studies have been carried out on the measurement of the tune and the beam lifetime with this new BPM system. 展开更多
关键词 数据处理程序 PM系统 合肥光源 嵌入式LINUX系统 EPICS 应用 开发 位置数据
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Commissioning the photocathode radio frequency gun:a candidate electron source for Hefei Advanced Light Facility 被引量:4
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作者 Wen-Xing Wang Cheng Li +11 位作者 Zhi-Gang He Shan-Cai Zhang Rui-Xuan Huang Wei-Wei Li Ping Lu Chuan Li Lei-Lei Tang Feng-Lei Shang Fang-Fang Wu Da-Chun Jia Hai-Yan Zhang Wei Wang 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2022年第3期1-9,共9页
The Hefei Advanced Light Facility(HALF)proposed by the National Synchrotron Radiation Laboratory(NSRL)is a diffraction-limited storage ring(DLSR),which plans to use a full energy linac as the injector.To ensure inject... The Hefei Advanced Light Facility(HALF)proposed by the National Synchrotron Radiation Laboratory(NSRL)is a diffraction-limited storage ring(DLSR),which plans to use a full energy linac as the injector.To ensure injection efficiency,the injection beam needs to have low emittance.Therefore,a photocathode radio frequency(RF)gun was developed in the HALF R&D project.The gun is designed to deliver high-quality electron bunches with a typically 0.5 nC charge and~4.5 MeV energy with low emittance.The initial system commission with an electron beam was completed at the end of 2020,and a stable 1.2–1.4 mm.mrad emittance with a bunch charge of 500 pC was demonstrated.In this paper,we report the experimental results and experience obtained during the commission,including the RF gun,drive laser system,and beam diagnostics. 展开更多
关键词 High-brightness electron beam Photoinjector laser shaping Transverse emittance
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Spatio-temporal Characteristics of Residential Land Growth in Hefei of Anhui Province, China 被引量:3
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作者 CHU Jinlong XU Jiangang GAO Shu 《Chinese Geographical Science》 SCIE CSCD 2007年第2期135-142,共8页
We used the maps of urban land-use in 1978, 1991, 1994, 2000 and 2004, and softwares such as ArcGIS, Fragstats to analyze the spatio-temporal process of urban residential space quantitatively. Some methods, such as di... We used the maps of urban land-use in 1978, 1991, 1994, 2000 and 2004, and softwares such as ArcGIS, Fragstats to analyze the spatio-temporal process of urban residential space quantitatively. Some methods, such as di- rection analysis and landscape pattern analysis, were employed. The results show that: 1) the residential land grew very rapidly in Hefei from 1978 to 2004, and the increased land was distributed mainly in the central city zone surrounded by a moat; however, after 1994, it was distributed mainly outside the 1th Ring Road; 2) the expansion speeds were very different in different directions: there exists a fastest expansion of residential land in the directions of NE-NNE, SW and SSE, and a slowest one in the directions of E and SEE; 3) the residential land growth went through four stages: slow circular expansion in 1978-1991, 'axes + fan wings' expansion in 1991-1994, more rapid circular expansion in 1994-2000 and 'fan-wings' expansion in 2000-2004; 4) the expansion intensity was also different in all directions in the period of 1978 to 1994, and the most was in SW and then NW; and 5) there were more and more residential land area, and the spatial agglomeration was improved increasingly. 展开更多
关键词 中国 安徽 合肥市 住宅土地 空间扩展
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Assessing ability of a wet swale to manage road runoff:A case study in Hefei, China 被引量:2
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作者 唐宁远 李田 葛军 《Journal of Central South University》 SCIE EI CAS CSCD 2016年第6期1353-1362,共10页
The ability of a wet swale,constructed in an area of poor soil permeability,to manage runoff from a roadway was monitored through 27 storm events over a period of 8 months.During the monitoring period,the wet swale re... The ability of a wet swale,constructed in an area of poor soil permeability,to manage runoff from a roadway was monitored through 27 storm events over a period of 8 months.During the monitoring period,the wet swale reduced the total runoff volume by 50.4%through exfiltration and evapotranspiration.The wet swale significantly decreased the influent pollutant concentrations,and the effluent mean concentrations of total suspended solids,total phosphorus,chemical oxygen demand,ammonium,oxidized nitrogen,and total nitrogen in the effluent were 31 mg/L,0.10 mg/L,29 mg/L,0.52 mg/L,0.35 mg/L and1.28 mg/L,respectively.Pollutant loads were also substantially reduced from 70%to 85%.Plant uptake played an important role in nutrient removal in the wet swale.Approximately half of the nitrogen(53.8%)and phosphorus(51.5%)that entered the wet swale was incorporated in above-ground plants.It is shown that wet swales are useful for managing runoff from roads in areas of poor soil permeability. 展开更多
关键词 路面径流 洼地 能力 污染物浓度 合肥 评估 中国 径流监测
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Research on Spatial Changes of Negative Air Ion Concentration in Hefei City 被引量:1
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作者 XIA Shang-guang YAN Ping +1 位作者 YE Fei LIU He-jun 《Meteorological and Environmental Research》 CAS 2012年第1期14-17,共4页
[Objective] The study aimed to discuss the spatial changes of negative air ion concentration in Hefei City.[Method] Based on the observation of air ions,temperature,relative humidity,the spatial changes of negative ai... [Objective] The study aimed to discuss the spatial changes of negative air ion concentration in Hefei City.[Method] Based on the observation of air ions,temperature,relative humidity,the spatial changes of negative air ion concentration in different districts of Hefei City were analyzed firstly,then the correlation between negative air ion concentration and meteorological factors was discussed.[Result] Air cleanliness index(CI) of the parks,residential areas,industrial regions,transport stations and prosperous commercial districts was 0.86,0.53,0.37,0.26 and 0.17 respectively,and the latter two regions suffered mild and moderate pollution separately.Daily variations of negative air ion concentration in the residential areas and parks of Hefei City were obvious,showing U shape,that is,the maximum values appeared in the morning and evening,while the minimum values could be found around 14:00.There was no distinctly regular variation of negative air ion concentration in the prosperous commercial districts,transport stations and industrial areas.In Hefei City,the concentration of negative air ions showed an increasing trend from the urban districts to the suburban districts;it was obviously higher in the residential areas and parks with numerous plants and waters compared with the prosperous commercial districts and transport stations.Negative air ion concentration correlated with relative humidity positively and temperature negatively,so the main meteorological factors influencing the negative air ion concentration in Hefei City were temperature and relative humidity.[Conclusion] The research could provide scientific references for city planning and greenbelt construction in future. 展开更多
关键词 空气负离子浓度 空间变化 合肥市 相对湿度 空气洁净度 绿化隔离带 商业区 模拟分析
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Observation of the nighttime nitrate radical in Hefei, China 被引量:1
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作者 LI Suwen LIU Wenqing XIE Pinua LI Ang QIN Min PENG Fumin ZHU Yanwu 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2008年第1期45-49,共5页
夜间硝酸盐基(NO3 ) 的观察被使用长路径执行微分光吸收光谱学(LP-DOAS ) 在 Hefei 的郊区,中国。NO3 和支持的参数的时间系列同时被测量一个星期(7 年 5 月 31 日 2006 年 6 月) 。结果显示 NO3 的平均集中是 15.6 pptv 与一 96 s 的... 夜间硝酸盐基(NO3 ) 的观察被使用长路径执行微分光吸收光谱学(LP-DOAS ) 在 Hefei 的郊区,中国。NO3 和支持的参数的时间系列同时被测量一个星期(7 年 5 月 31 日 2006 年 6 月) 。结果显示 NO3 的平均集中是 15.6 pptv 与一 96 s 的平均寿命,而, NO3 生产率从 8 × 105/(cm3 · s ) 变化了到 2.98 × 107/(cm3 · s ) 。而且,计算 N2O5concentration 在 380 点平均 pptv。数据的分析显示直接水池可能在这个运动期间正在统治 NO3 损失进程。结果与在边界层的另外的运动相比。 展开更多
关键词 硝酸盐 夜间 分光吸收光谱法 大气污染物 中国 合肥 大气监测
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Hefei utility negative ions test equipment with RF source:commissioning and first results 被引量:3
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作者 韦江龙 谢亚红 +8 位作者 将才超 梁立振 崔庆龙 陈世勇 许永建 王艳 张黎 谢远来 胡纯栋 《Plasma Science and Technology》 SCIE EI CAS CSCD 2018年第12期125-131,共7页
In order to study the key technology and physics of RF driven negative ion source for neutral beam injector in China, the Hefei utility negative ions test equipment with RF source was developed at Institute of Plasma ... In order to study the key technology and physics of RF driven negative ion source for neutral beam injector in China, the Hefei utility negative ions test equipment with RF source was developed at Institute of Plasma Physics, Chinese Academy of Sciences(ASIPP). Its negative ion source can be equipped with single or double RF drivers. There is a plasma expansion chamber with depth of 19 mm and an enhanced filter field. A three electrodes negative ion accelerator was employed to extract and accelerate the negative ions, which are plasma grid,extraction grid and ground grid. And there are several diagnostic tools for the plasma and beam parameters measurement. The characteristics of plasma generation, negative ion production and extraction were studied on the test equipment. The negative ion beam was extracted from the RF driven negative ion source for the first time. The detailed structure and main results are presented in this article. 展开更多
关键词 离子加速器 测试设备 否定 RF 设备采购 用途 中国科学院 原料
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Research on tune feedback of the Hefei Light SourceⅡbased on machine learning 被引量:1
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作者 Yong-Bo Yu Gong-Fa Liu +3 位作者 Wei Xu Chuan Li Wei-Min Li Ke Xuan 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2022年第3期45-52,共8页
The theory of tune feedback correction and the principle of a feedback algorithm based on machine learning are introduced,with a focus on the application of lasso regression for tune feedback correction.Simulation ver... The theory of tune feedback correction and the principle of a feedback algorithm based on machine learning are introduced,with a focus on the application of lasso regression for tune feedback correction.Simulation verification and online feedback correction results are presented.The results show that,after applying machine learning,the feedback accuracy of the tune feedback system was higher,and the betatron tune stability was further improved. 展开更多
关键词 Storage ring Tune feedback Machine learning Lasso regression
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High resolution tomography of the Tanlu fault zone near Hefei with passive seismic and magnetotelluric linear array data 被引量:1
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作者 Jian Xu Kangdong Wang +5 位作者 Junlun Li Ning Gu Ning Ding Jiawei Qian Wen Yang Haijiang Zhang 《Earthquake Science》 2021年第1期24-35,共12页
As the largest fault trending NNE-SSW to NE-SW in the eastern Eurasia Continent,the Tanlu fault zone(TLFZ)extends over 2,400 km within China,roughly from Wuxue,Hubei Province,to Russia.Since the Quaternary period,the ... As the largest fault trending NNE-SSW to NE-SW in the eastern Eurasia Continent,the Tanlu fault zone(TLFZ)extends over 2,400 km within China,roughly from Wuxue,Hubei Province,to Russia.Since the Quaternary period,the TLFZ has been an earthquake-prone area in eastern China where several major earthquakes resulted by tectonic compression occurred,causing tremendous casualties and significant economic losses.Many studies on different segments of the TLFZ have been carried out in the past few decades.However,numerous key questions regarding the fault zone remain unanswered due to a lack of clear subsurface characterization and fault delineation.In this study,we present high-resolution tomographic results across the TLFZ to the east of Hefei,where one 22-km-long passive seismic array with densely spaced short-period nodes,and a 24-km-long magnetotelluric array were deployed adjacent to each other.We find the velocity and resistivity variations are highly consistent with known surface geology.Sharp property contrasts in both the seismic shear wave velocity and electrical resistivity profiles clearly delineate the Tanlu F1 fault(TLF-1)near Hefei.More interestingly,an upwelling with distinct high velocity is imaged within the Hefei Basin to the west of the TLF-1,whereas a slanted block with lowvelocity and low-resistivity seems to cut into or thrust upon the high-grade to low-grade middle-pressure rocks in the Zhangbaling uplift right below the Tanlu F2 ductile shear fault(TLF-2).The presented results show a new approach to characterize deep subsurface structure of the TLFZ beyond 2-km depths using passive data,which it is often difficult for active seismic surveys with refracted and reflected waves to image. 展开更多
关键词 Tanlu fault zone deep structures ambient noise tomography MAGNETOTELLURICS ductile shear zone
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Environmental Water Price Based on Water Environment Capacity and Ecological Water Consumption: A Case Study of Hefei 被引量:1
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作者 Yuzhen Duan Guijian Liu +1 位作者 Chong Ren Xiaobao Peng 《Journal of Geoscience and Environment Protection》 2016年第4期100-109,共10页
With the development and reform of water price policy, the most common view is that the total cost of water price can reflect the tradable traits of water resources, which can enhance the water use efficiency and achi... With the development and reform of water price policy, the most common view is that the total cost of water price can reflect the tradable traits of water resources, which can enhance the water use efficiency and achieve water resources sustainable utilization. Besides in actual pricing operation, from the angle of protection cost, water price characterizes the cost of controlling pollution and protecting water environment. Based on the two factors of water environment capacity and ecological water consumption embodied by the environment water price, this paper puts forward an effective environmental water price calculation model based on three elements of sewage treatment fee, ecological water price and water quality maintenance fee. And this paper takes the data of Hefei as an example, calculates reasonable environmental price, comparing which with the existing price, and finds the main existing problem which needs to be solved urgently in management. 展开更多
关键词 Environmental Water Price Sewage Treatment Fee Ecological Water Price Water Quality Maintenance Fee
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Water Resource Pricing Study Based on Water Quality Fuzzy Evaluation: A Case Study of Hefei City 被引量:2
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作者 Yuzhen Duan Guijian Liu 《Computational Water, Energy, and Environmental Engineering》 2016年第4期99-111,共13页
Price plays an important role in water resources management. The price of water resources can also be considered as a “water resource tax” which reflects the value and opportunity cost of water, and people will pay ... Price plays an important role in water resources management. The price of water resources can also be considered as a “water resource tax” which reflects the value and opportunity cost of water, and people will pay for the right to use water. Currently, the water resource fees’ effect of regulating resource differential revenues is not manifest and it’s not enough to reflect the principle of paid use of resources as well as regulating resources differential revenues. Due to the ambiguity and complexity of water resources price, this paper uses methods relating to fuzzy mathematics for modeling and processing. The study had a comprehensive consideration of five factors including water quality, water resources per capita, household consumption level, per capita GNP, population or population density to evaluate the water resource price. 展开更多
关键词 Water Quality Fuzzy Evaluation Water Resource Price Pricing Model
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