检索结果-南通市图书馆

Health risk assessments of polycyclic aromatic hydrocarbons and chlorinated/brominated polycyclic aromatic hydrocarbons in urban air particles in a haze frequent area in China

引用

Emerging Contaminants 2020年第1期6卷 172-178页

作者： Miwei Shi Rongzhi Zhang Yunxia Wang Yan Zhang Yuan Zhang Yanjie Zhang Institute of geographical Science Hebei Academy of SciencesEngineering Technology Research Center of Geographic Information Development and Application of HebeiShijiazhuang050011China

The potential threats of polycyclic aromatic hydrocarbons(PAHs)and chlorinated/brominated PAHs(Cl/Br-PAHs)to human health from particulate matter in the urban ambient air were studied using human health risk assessments.The risk to human health caused by exposure to PAHs was evaluated in Shijiazhuang,China,from January to December 2018.The PAHs concentration range was 16.02e475.21 ng/m3 and the toxic equivalent was 13.605 ng/m3.For adults,the average carcinogenic risk caused by respiratory exposure was 5.163×10^-6 and the resulting loss of life expectancy was 32.10 min.The human health risks of respiratory exposure to Cl/Br-PAHs in atmospheric samples from the Haidian District,Beijing,China,were evaluated from November 2017 to July 2018.The concentration ranges for the Cl-and Br-PAHs were 60.38e482.17 pg/m3 and 1.32e25.35 pg/m3,respectively.The average carcinogenic equivalent concentrations were 0.3274 pg/m3 and 0.0061 pg/m3 for the Cl-and Br-PAHs,respectively.For adults the average carcinogenic risks caused by respiratory exposure were 1.243×10^-10 and 2.316×10^-12 for the Cl-and Br-PAHs,respectively.The resulting loss of life expectancy values were 0.001 min(Cl-PAHs)and 0.00 min(Br-PAHs).The pollution concentrations and toxic equivalents of the Cl/Br-PAHs in Beijing and of the PAHs in Shijiazhuang both showed toxicity was high in the winter.The average carcinogenic risk for exposure of adults to PAHs in Shijiazhuang was low with certain potential hazards.The concentration of Cl-PAHs in Beijing was higher than that of Br-PAHs,and the average carcinogenic risk for exposure of adults to Cl/Br-PAHs was very low with slight harm.

关键词： Particulate matter Persistent organic pollutant Polycyclic aromatic hydrocarbon Chlorinated/brominated polycyclic aromatic hydrocarbon Health risk assessment

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Brominated dioxins and furans in a cement kiln co-processing municipal solid waste

引用

Journal of Environmental Sciences 2019年第5期31卷 339-345页

作者： Lili Yang Yuyang Zhao Miwei Shi Minghui Zheng Yang Xu Cui Li Yuanping Yang Linjun Qin Guorui Liu State Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences University of Chinese Academy of Sciences Hebei Engineering Research Center for Geographic Information Application Institute of Geographical Sciences Hebei Academy of Sciences

A field study and theoretical calculations were performed to clarify the levels, profiles, and distributions of polybrominated dibenzo-p-dioxins and dibenzofurans(PBDD/Fs) in a cement kiln co-processing solid waste, with a focus on the PBDF formation mechanism.The raw materials contributed greatly to input of PBDD/Fs into the cement kiln. The PBDD/F concentrations in the raw materials were much higher than those in particle samples from different process stages in the cement kiln. The PBDD/F concentrations in the clinkers were1.40% of the concentrations in the raw materials, which indicated that the high destruction efficiencies for PBDD/Fs by cement kiln. PBDD/F distribution patterns in particle samples collected from different process stages indicated the cement kiln backend was a major site for PBDD/F formation. PBDFs with high levels of halogenation, such as heptabrominated furans(Hp BDF), were the dominant contributors to the total PBDD/F concentrations and accounted for 42%–73% of the total PBDD/F concentrations in the particle samples. Our results showed that co-processing of municipal solid waste in a cement kiln may influence the congener profile of PBDD/Fs, especially for the higher halogenated PBDD fraction. In addition, there were significant correlations between the decabromodiphenyl ether and heptabrominated furan concentrations, which is an indicator of transformation from polybrominated diphenyl ethers to PBDD/Fs. Theoretical calculations were performed and demonstrated that elimination of HBr and Br_2 from polybrominated diphenyl ethers were the dominant formation pathways for PBDD/Fs. These pathways differed from that for polychlorinated dibenzo-p-dioxins and dibenzofurans(PCDD/Fs).

关键词： Polybrominated dibenzo-p-dioxin and dibenzofuran(PBDD/F) Cement kiln Municipal solid waste Dioxin Formation mechanism

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

The varying fetch effect of aeolian sand transport above a gobi surface and its implication for gobi development process

引用

International Soil and Water Conservation research 2022年第4期10卷 623-634页

作者： Chunlai Zhang Guoru Wei Xueyong Zou Zhenting Wang Qing Li Xuesong Wang State Key Laboratory of Earth Surface Processes and Resource Ecology MOE Engineering Research Center of Desertification and Blown-sand ControlFaculty of Geographical ScienceBeijing Normal UniversityBeijing100875China Northwest Institute of Eco-Environment and Resources Chinese Academy of SciencesLanzhou730000PR China Hebei Engineering Research Center for Geographic Information Application Institute of Geographical SciencesHebei Academy of SciencesShijiazhuang050011China

The Gobi deserts are important landscapes and major sandstorm source areas in arid northwestern China.Unsaturated sand flow and decreasing sand supply capacity is well known as the basic characteristics of gobi surface,but relatively little attention has been paid to the fetch effect of sand transport which is closely related to sand supply and indicative of wind erosion process in gobi.Using a field experiment,we investigated the spatial and temporal variations on a manually disturbed gobi surface downwind a sand-blocking belt and a sand-fixing belt by measuring the sand transport rate and the height profile of flux density at different fetch lengths during a sequence of wind erosion events.Results showed that the sand supply capacity determined the critical fetch length(Lc)for the sand transport rate so that the fetch effect varied with wind erosion proceeding due to depletion of erodible material.The height profile of flux density above the surface followed two distributions:an exponential decrease with increasing height,which commonly occurred above the newly treated gobi surface during the early wind erosion events;or a Lorentzian distribution with a peak flux at a certain height,which often happened in the later wind erosion events.The varying fetch effect,decreasing sand transport rates,and the nonerodible area expanded downwind are an epitome of the gobi development and expansion process from the perspective of wind erosion.

关键词： Gobi Wind erosion Sand transport Fetch effect Gobi development

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

构建准层状自空穴掺杂SnSe取向薄膜获得优异热电功率因子和输出功率密度

引用

Science Bulletin 2023年第22期68卷 2769-2778,M0005页

作者：薛宇利王晴高志钱鑫王江龙闫国英陈明敬赵立东王淑芳李志亮 hebei Key Laboratory of Optic-Electronic information and Materials Key Laboratory of High-Precision Computation and Application of Quantum Field Theory of Hebei ProvinceCollege of Physics Science and TechnologyHebei UniversityBaoding 071002China School of Materials Science and engineering Beihang UniversityBeijing 100191China engineering research center of Zero-Carbon Energy Buildings and Measurement Techniques Ministry of EducationHebei UniversityBaoding 071002China

热电技术可以实现热能与电能的相互转换,其开发利用对于缓解能源危机具有重要意义.近10年来,SnSe因其潜在的高能量转换效率、绿色环保和低成本特性而备受关注.但SnSe的固有载流子浓度低(约10~(17)cm^(-3)),导致其功率因子偏低,从而限制... 详细信息

热电技术可以实现热能与电能的相互转换,其开发利用对于缓解能源危机具有重要意义.近10年来,SnSe因其潜在的高能量转换效率、绿色环保和低成本特性而备受关注.但SnSe的固有载流子浓度低(约10~(17)cm^(-3)),导致其功率因子偏低,从而限制了SnSe基器件的输出功率密度.因此,探索新的载流子浓度优化策略对于SnSe的应用至关重要.此外,与三维块体相比,二维薄膜更易和现代半导体工艺相兼容,在热电微纳米器件的构筑和应用方面具有独特优势.本文报道了一种利用非原位硒化技术,通过电荷转移和自空穴掺杂效应来优化a轴取向SnSe基薄膜的载流子浓度.当硒化时间为20 min时,薄膜载流子浓度可提高至10~(18)cm^(-3)数量级,形成了准层状的自空穴掺杂SnSe基薄膜,其功率因子在600 K时达到了5.9μW cm^(-1)K^(-2).由硒化处理的SnSe基取向薄膜构筑的热电发电机在50和90 K的温差下分别具有约83、838μW cm^(-2)的超高功率密度.非原位硒化技术可以有效提高SnSe基薄膜的载流子浓度,为其他热电材料性能优化提供了一种新策略.

关键词： Thermoelectric property Thin film Tin selenide Post-selenization Carrier concentration

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

application of BeiDou navigation satellite system in emergency rescue of natural hazards: a case study for field geological survey of Qinghai−Tibet plateau

引用

Geo-Spatial information Science 2018年第4期21卷 294-301页

作者： Ming Hao Jianlong Zhang Ruiqing Niu Changrong Deng Hong Liang National engineering research center for geographic information System WuhanChina Chengdu center of China Geological Survey ChengduChina

In recent years,geological and mineral resources exploration in China has expanded to deep hinterland of the Qinghai−Tibet Plateau and other regions with complex geological conditions.The special natural conditions of Qinghai−Tibet Plateau determine the characteristics of“life-forbidden zone”that is characterized by alpine hypoxia,changeable weather,complex road conditions,and beast attack.In particular,the work in wild depopulated zones with severe environment and poor communications imposes serious threats to the life safety of geological personnel.Therefore,how to guarantee the safety of geological personnel working on the Qinghai−Tibet Plateau and how to reduce or even avoid casualty of geological personnel have currently become the urgent challenge.In this study,an emergency rescue information system for field geological survey is constructed based on BeiDou Navigation Satellite System.A case study of emergency rescue has been conducted in the depopulated zone of the Qinghai−Tibet Plateau and good effects have been achieved,providing security assurance for personnel engaged in field geological survey on the Qinghai−Tibet Plateau and technical support for the emergency rescue in case of natural hazards on the Qinghai−Tibet Plateau.The BeiDou Navigation Satellite System(BDS)can be effectively used to locate and communicate in the emergency rescue for rigorous Geological survey task where there is no network signal for the mobile phone,and the emergency rescue guarantee system is independent,reliable,and relatively cheap.The application value of BDS is demonstrated in the geological field.

关键词： BeiDou navigation satellite system(BDS) natural hazard emergency rescue Qinghai−Tibet plateau

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

A balanced decomposition approach to real-time visualization of large vector maps in CyberGIS

引用

Frontiers of Computer Science 2015年第3期9卷 442-455页

作者： Mingqiang GUO Ying HUANG Zhong XIE Faculty of information and engineering China University of Geosciences Wuhan 430074 China geographic information Systems Software and application Project research center of the Educational Department China University of Geosciences Wuhan 430074 China

With the dramatic development of spatial data in- frastructure, CyberGIS has become significant for geospatial data sharing. Due to the large number of concurrent users and large volume of vector data, CyberGIS faces a great chal- lenge in how to improve performance. The real-time visual- ization of vector maps is the most common function in Cyber- GIS applications, and it is time-consuming especially when the data volume becomes large. So, how to improve the effi- ciency of visualization of large vector maps is still a signif- icant research direction for GIScience scientists. In this re- search, we review the existing three optimization strategies, and determine that the third category strategy （i.e., parallel optimization） is appropriate for the real-time visualization of large vector maps. One of the key issues of parallel optimiza- tion is how to decompose the real-time visualization tasks into balanced sub tasks while taking into consideration the spatial heterogeneous characteristics. We put forward some rules that the decomposition should conform to, and design a real-time visualization framework for large vector maps. We focus on a balanced decomposition approach that can assure efficiency and effectiveness. Considering the spatial hetero- geneous characteristic of vector data, we use a ＂horizontal grid, vertical multistage＂ approach to construct a spatial point distribution information grid. The load balancer analyzes the spatial characteristics of the map requests and decomposes the real-time viewshed into multiple balanced sub viewsheds.Then, all the sub viewsheds are distributed to multiple server nodes to be executed in parallel, so as to improve the real- time visualization efficiency of large vector maps. A group of experiments have been conducted by us. The analysis results demonstrate that the approach proposed in this research has the ability of balanced decomposition, and it is efficient and effective for all geometry types of vector data.

关键词： real-time visualization large vector map bal-anced decomposition CyberGIS load balance

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Impacts of climate warming and crop management on maize phenology in northern China

引用

Journal of Arid Land 2019年第6期11卷 892-903页

作者： XIAO Dengpan ZHAO Yanxi BAI Huizi HU Yukun CAO Jiansheng engineering Technology research center Geographic Information Development and Application of HebeiInstitute of Geographical SciencesHebei Academy of SciencesShijiazhuang 050011China center for Agricultural Resources research Institute of Genetics and Developmental BiologyChinese Academy of SciencesShijiazhuang 050021China

Climate warming has and will continue to exert a significantly impact on crop phenology in the past and coming decades.Combining observed data of phenology and a crop growth model provides a good approach for quantitating the effects of climate warming and crop management on crop phenology.The purpose of this study is to determine the impacts of temperature change, sowing date(SD) adjustment and cultivar shift on maize phenology in northern China during 1981–2010.Results indicated that climate warming caused anthesis date(AD) and maturity date(MD) of maize to advance by 0.2-5.5 and 0.6-11.1 d/10 a, respectively.Due to climate-driven changes in maize phenology, three growth periods of maize, i.e., vegetative growth period(VGP;from sowing to anthesis), reproductive growth period(RGP;from anthesis to maturity) and whole growth period(WGP;from sowing to maturity) shortened by 0.2-5.5, 0.4-5.6 and 0.6-11.1 d/10 a, respectively.With SD adjustment(i.e., SD advancement), AD and MD occurred early by 0.5-2.6 and 0.1-3.4 d/10 a, respectively.SD adjustment caused duration of VGP of maize to prolong.However, duration of RGP slightly shortened by 0.1-1.3 d/10 a.Furthermore, due to cultivar shift, MD of maize significantly delayed by 4.9-12.2 d/10 a.Durations of VGP, RGP and WGP of maize prolonged by 0.2-4.1, 1.6-8.4 and 4.3-11.8 d/10 a, respectively.In conclusion, our results indicated that cultivar shift, to some extent, could mitigate the negative impact of climate warming on maize phenology.

关键词： anthesis date maturity date sowing date growth period cultivar shift

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

An asynchronous Geoprocessing Workflow and its application to an Antarctic ozone monitoring and mapping service

引用

International Journal of Digital Earth 2016年第2期9卷 156-170页

作者： Chao Yang Zhong Xie Zhanya Xu Faculty of information engineering China University of GeosciencesWuhanChina National engineering research center for geographic information System China University of GeosciencesWuhanChina

The integration of Sensor Web Enablement services with other Open Geospatial Consortium(OGC)Web Services as Geospatial Processing Workflows(GPW)is essential for future Sensor Web application scenarios.With the help of GPW technology,distributed and heterogeneous OGC Web Services can be organized and integrated as compound Web Service applications that can direct complicated earth observation tasks.Under the Sensor Web environment,asynchronous communications between Sensor Web Services are common.We have proposed an asynchronous GPW architecture for the integration of Sensor Web Services into a Web Service Business Process Execution Language workflow technology.We designed a Sensor information Accessing and Processing workflow,an asynchronous GPW instance,to take an experiment of observing and mapping ozone over Antarctica.Based on our results,our proposed asynchronous workflow method shows the advantages of taking environmental monitoring and mapping tasks.

关键词： Sensor Web OGC Web Service asynchronous workflow OMI ozone monitoring

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Analysis of Jiangsu Tidal Flats Reclamation from 1974 to 2012 Using Remote Sensing

引用

China Ocean engineering 2015年第1期29卷 143-154页

作者：赵赛帅刘永学李满春孙超周旻曦张荷霞 Jiangsu Provincial Key Laboratory of geographic information Science and Technology Nanjing University Collaborative Innovation center for the South China Sea Studies Department of Geographic Information ScienceNanjing University Jiangsu center for Collaborative Innovation in geographical information Resource Development and application Nanjing University

Jiangsu has the most abundant tidal flat resources among China＇s coastal provinces. To ease the conflict between the growing population and shrinking usable land and to promote regional sustainable development, large-scale coastal reclamation development activities have been performed in Jiangsu Province since 1949. The present study has integrated multi-source remote sensing images during 1974 to 2012 by using a Multi-point Fast Marching Method （MFMM） to extract the Jiangsu coastal reclamation areas for different time periods. The temporal and spatial patterns of the extent and elevation of the reclamation areas were analysed in order to determine the unused potential for future reclamation. It will provide information necessary to support the development and construction of tidal flats in Jiangsu. Results show that：（1） the reclaimed tidal fiats along the Jiangsu coast cover more than 19.86×10^4 hm^2, of which 13.97×10^4 hm^2 is located in Yancheng, 4.84×10^4 hm^2 in Nantong, and 1.05×10^4 hm^2 in Lianyungang; （2） the average elevation of the reclaimed Jiangsu tidal flats has gradually decreased over the last 40 years, while those in Dongtai and Rudong have showed particularly accelerated decrease since the 1990s; and （3） in 2012, very few unused tidal flats two meters above the sea level are left along the Jiangsu coast, and mainly concentrated in Yancheng. As there are still reserving some coastal land resources between 0-2 m, providing us with a potential for future development. All of these findings may be useful for researchers and local authorities for the development and utilization of tidal flat resources in Jiangsu.

关键词： tidalflats remote sensing Jiangsu coast developmentpotential reclamation

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

雅鲁藏布江中游全新世风成活动历史及其与印度季风变化的关系

引用

Journal of geographical Sciences 2020年第12期30卷 2002-2014页

作者：李拓宇张继峰伍永秋杜世松莫多闻廖奕楠陈智童刘建宝李庆 Capital Normal University Beijing 100048China Key Laboratory of Alpine Ecology(LAE) Institute of Tibetan Plateau ResearchCASBeijing 100101China MOE engineering center of Desertification and Blown-sand Control Beijing Normal UniversityBeijing 100875China Laboratory for Earth Surface Processes Ministry of EducationCollege of Urban and Environmental SciencesPeking UniversityBeijing 100871China Institute of geographical Sciences Hebei Engineering Research Center of Geographic Information ApplicationHebei Academy of SciencesShijiazhuang 050011China

Widespread aeolian deposits on the Tibetan Plateau(TP)have provided valuable palaeoclimatic information.However,the primary factors(e.g.,climate factors,human activity,and vegetation cover)controlling aeolian deposition remain elusive.In this paper,we use a dataset that comprises new and published ages of Holocene aeolian sand and loess in the middle reaches of the Yarlung Zangbo River to identify the primary controlling factors and palaeoclimatic implications of aeolian deposition.Several intervals of enhanced aeolian accumulation centered at 8.5-7.8,6.4-5.8,4.5-4.0,3.1-1.8,and 0.9 ka are identified,generally consistent with regional low rainfall events and weak Indian summer monsoon(ISM).This suggests that regional wetness,dominated by the ISM,may play a key role in modulating dust emissions and aeolian deposition on centennial timescales.Our results show that on centennial-to millennial-scales,ISM activity can be reconstructed by non-continuous aeolian deposits in the monsoon dominated TP.

关键词： Holocene aeolian activity dust Indian summer monsoon Tibetan Plateau

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：