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Dragons Leap with Each Passing Year, Intangible Heritage Grows Fragrant Beijing Shadow Puppetry Outreach Activities
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作者 Xin Wen 《China & The World Cultural Exchange》 2024年第3期22-23,共2页
Since ancient times,the Chinese New Year has been the most important festival for the Chinese nation,and"celebrating the Chinese New Year in museums"has gradually become a new trend in recent years.To enrich... Since ancient times,the Chinese New Year has been the most important festival for the Chinese nation,and"celebrating the Chinese New Year in museums"has gradually become a new trend in recent years.To enrich the cultural offerings during the holiday period and let the general audience experience the strong festive atmosphere in museums,on February 22 and 23,2024,on the eve of the Lantern Festival,the China Arts and Crafts Museum(China Intangible Cultural Heritage Museum)successfully held the"Encounter with Intangible Heritage""Capital Colors Shadow Play:Bejing Shadow Puppetry Outreach Activities." 展开更多
关键词 SHADOW offering reach
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Spatial-temporal Variation Characteristics of Water Quality in the Lower Reaches of the Nenjiang River
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作者 Xiangzhe MENG Jing WANG +4 位作者 Yinglin XIE Fei PENG Chunsheng WEI Xin TIAN Lunwen WANG 《Meteorological and Environmental Research》 2024年第1期67-71,共5页
As an important river in the western part of Jilin Province,the lower reach of the Nenjiang River is an important wetland water source conservation area in Jilin Province.Within the watershed,it governs the Momoge Wet... As an important river in the western part of Jilin Province,the lower reach of the Nenjiang River is an important wetland water source conservation area in Jilin Province.Within the watershed,it governs the Momoge Wetland,the Xianghai Wetland,and the Danjiang Wetland in Jilin Province.The main problem in the lower reaches of the Nenjiang River is the uneven distribution of water resources in time and space,and the intensification of land salinization.Zhenlai County and Da an City in the Nenjiang River Basin have sufficient surface water resources,with surface water as the drinking water source.Baicheng City and Tongyu County have scarce surface water resources,and both use groundwater as their domestic water source.The main polluted section in the basin is the Xianghai Reservoir,and the annual water quality evaluation is Class V.However,the water quality of the Tao er River,the main stream of the Nenjiang River,is significantly better than that of the Xianghai Reservoir.In order to better study the water environmental pollution situation in the Nenjiang River basin,monitoring data from five sections of non seasonal rivers in the basin from 2012 to 2021 were selected for studying water quality.This in-depth exploration of the water pollution status and river water quality change trends in the Nenjiang River basin is of great significance for future rural development,agricultural pattern transformation,and the promotion of water ecological civilization construction. 展开更多
关键词 Lower reaches of the Nenjiang River Water quality Spatial-temporal variation
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欧盟REACH法规要求解析及汽车产品管控建议
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作者 邹骁 何玉松 《上海汽车》 2024年第1期59-62,共4页
欧盟REACH立法宗旨是保护人类健康和环境安全,本质上也是技术贸易壁垒的重要组成部分,是我国汽车产品出口面临的重大挑战,需企业谨慎应对。基于汽车出口经验,文章针对法规跟踪与机制建立、REACH合规管控的关键方式和有害物质替代技术3... 欧盟REACH立法宗旨是保护人类健康和环境安全,本质上也是技术贸易壁垒的重要组成部分,是我国汽车产品出口面临的重大挑战,需企业谨慎应对。基于汽车出口经验,文章针对法规跟踪与机制建立、REACH合规管控的关键方式和有害物质替代技术3个方面进行阐述,期望能为汽车产品REACH管控提供一些参考。 展开更多
关键词 欧盟reach法规 reach合规管控 有害物质替代技术 汽车
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欧盟REACH法规新增5项SVHC高关注物质
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《聚氨酯工业》 CAS 2024年第1期25-25,共1页
2024年1月23日,欧洲化学品管理署(ECHA)正式公布实施第30批5项SVHC高关注物质(又称:候选授权物质清单)。截至当前,SVHC高关注物质总数共计240项,本次新增物质详细信息如下:(1) 2,4,6-三叔丁基苯酚(2,4,6-TTBP),主要用作橡胶防老剂、抗... 2024年1月23日,欧洲化学品管理署(ECHA)正式公布实施第30批5项SVHC高关注物质(又称:候选授权物质清单)。截至当前,SVHC高关注物质总数共计240项,本次新增物质详细信息如下:(1) 2,4,6-三叔丁基苯酚(2,4,6-TTBP),主要用作橡胶防老剂、抗氧剂。其抗氧化效果与264相当,也可用在乳胶、聚烯烃塑料中,同时也是制备亚磷酸酯类抗氧剂633、641的主要原材料。纳入原因:生殖毒性(第57c条)、持久性、生物积累性和毒性(PBT)(第57d条)。 展开更多
关键词 橡胶防老剂 聚烯烃塑料 化学品管理 欧盟reach法规 叔丁基苯酚 抗氧剂 高关注物质 SVHC
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吉利某车型项目K-REACH排查分析及总结
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作者 王慧莹 魏文博 +1 位作者 张文华 王睿 《汽车零部件》 2024年第7期64-67,共4页
全球化趋势加剧,影响着世界各行各业。国内各车企纷纷出台全球化策略,意在扩大业务版图。而规避合规问题是产品出口所需要考虑的关键问题之一。汽车零部件出口韩国时,需要应对韩国禁限用物质法规,其中韩国《化学品注册与评估法案》(K-RE... 全球化趋势加剧,影响着世界各行各业。国内各车企纷纷出台全球化策略,意在扩大业务版图。而规避合规问题是产品出口所需要考虑的关键问题之一。汽车零部件出口韩国时,需要应对韩国禁限用物质法规,其中韩国《化学品注册与评估法案》(K-REACH)整体上基于欧盟《化学品注册、评估、授权和限制》(EU-REACH)法规理念,对化学物质和下游产品进行管控。结合吉利某车型项目的K-REACH排查经验展开,对排查方案和结果进行介绍、分析和总结,并对车企K-REACH长期合规提出建议。 展开更多
关键词 K-reach 汽车 排查
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Responses of vegetation cover to the Grain for Green Program and their driving forces in the He-Long region of the middle reaches of the Yellow River 被引量:7
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作者 JianXiang LIU ZhiGuang LI +3 位作者 XiaoPing ZHANG Rui LI XianChun LIU HanYang ZHANG 《Journal of Arid Land》 SCIE CSCD 2013年第4期511-520,共10页
The implementation of the Grain for Green Program is a great breakthrough in the history of China's ecological environment construction,which can control soil erosion effectively,increase land productivity and improv... The implementation of the Grain for Green Program is a great breakthrough in the history of China's ecological environment construction,which can control soil erosion effectively,increase land productivity and improve the ecological environment.To investigate the eco-environmental benefits brought by the Grain for Green Program,the spatiotemporal variations of vegetation cover in the growing season from 2000 to 2010 across the Hekou-Longmen (He-Long) region were analyzed by using remote sensing information,meteorological data and land use data.Moreover,the impacts of climate and human activities on vegetation change were evaluated objectively.Annual vegetation cover in the growing season increased very significantly.Increased vegetation cover occurred in 98.7% of the region,of which the area for vegetation cover improved slightly constituted 79.8% of the whole area.Vegetation moderately improved was mainly distributed in the south of the He-Long region,covering 9.6% of the area,and the area for vegetation basically unchanged concentrated in the middle and upper reaches of the Wuding River.Precipitation was found to be an important natural factor influencing vegetation cover change.The area of vegetation cover showing a significantly positive correlation with precipitation occupied 22.14% of the region.As driven by policies from the Grain for Green Program,forestland increased significantly and land use structure became more intensive.Human activities played a positive and effective role in the protection,restoration and improvement of vegetation in the places where vegetation cover was basically unchanged,even though precipitation declined greatly,and vegetation improved moderately with massive increases of forestland and grassland. 展开更多
关键词 vegetation cover precipitation land use the Grain for Green Program the he-long region
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Living environment shaped residents’willingness to pay for ecosystem services in Yangtze River Middle Reaches Megalopolis,China 被引量:1
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作者 Guanshi Zhang Qi Zhang +3 位作者 Xin Yang Ruying Fang Hongjuan Wu Sen Li 《Geography and Sustainability》 CSCD 2023年第3期213-221,共9页
Profound understanding on the diversity of local residents’willingness to pay(WTP)for ecosystem services(ESs)may aid evaluation of policy impacts by uncovering trade-offs and synergies for achieving sustainable envir... Profound understanding on the diversity of local residents’willingness to pay(WTP)for ecosystem services(ESs)may aid evaluation of policy impacts by uncovering trade-offs and synergies for achieving sustainable environmental resource management.However,the reasons for the spatial preference heterogeneity of WTP are still unclear.In this study,an extensive survey with 4,580 residents in the Yangtze River Middle Reaches Megalopolis(YRMRM),central China,was carried out to investigate the public’s WTP to maintain and improve ESs.We identified key influencing factors and explored how they shaped the preference heterogeneity in WTP by random forest model and surface fitting method.Our results showed that 81.4% of residents reported WTP for ESs greater than zero.Water supply,waste treatment,food supply and raw material supply were the preferred ESs for residents.Living environment factors(i.e.,extent of farmland,water and forest near the residence)were found as the key drivers of WTP.Proximity to farmland,water and forests resulted in high WTP values for a series of specific ESs.The reasons for the heterogeneity of WTP are(1)the difference in proximity to farmland,water and forest(i.e.,the contributor to ESs),(2)the divergence of local residents’preferences for ESs.This study disclosed the heterogeneity and causes of public preferences in YRMRM,which could help policy and decision makers to develop eco-compensation initiatives towards conservative and sustainable use of the environmental resources. 展开更多
关键词 Ecosystem services Willingness to pay Living environment Spatial heterogeneity Yangtze River Middle reaches Megalopolis
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基于数值模拟的澄通感潮河段水源地预警站设置研究 被引量:3
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作者 徐振山 王苏东 +2 位作者 丁宏伟 杨柳俊 陈永平 《河海大学学报(自然科学版)》 CAS CSCD 北大核心 2024年第4期61-69,共9页
针对突发性水污染事件可能严重影响水源地取水,而现有研究针对感潮河段水源地预警站的确定方法尚无系统论述的问题,基于长江澄通感潮河段水动力-水质耦合数学模型,在厘清径潮共同作用下该河段污染物扩散输运规律的基础上,初步确定了长... 针对突发性水污染事件可能严重影响水源地取水,而现有研究针对感潮河段水源地预警站的确定方法尚无系统论述的问题,基于长江澄通感潮河段水动力-水质耦合数学模型,在厘清径潮共同作用下该河段污染物扩散输运规律的基础上,初步确定了长青沙和狼山水源地的预警站位置和数量;结合影响水源地的潜在污染源分布特征和污染物累积特征对预警站进行了空间校核,利用预警响应时效性对预警站进行了时间校核,最终确定了两水源地上下游共4个预警站的位置;基于预警站位置水质与水源地位置水质的相关性确定了长青沙和狼山水源地的应急响应方案,并给出了苯酚泄漏的风险响应限值。 展开更多
关键词 突发性水污染 感潮河段 数值模拟 预警站 澄通感潮河段
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An Information Entropy-Based Methodology to Construct the Avulsion Threshold in the Tail Reach of the Estuarine Alluvial Plain
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作者 YANG Zhuo-yuan XIA Jun-qiang +3 位作者 DENG Shan-shan ZHOU Mei-rong JI Zu-wen YU Xin 《China Ocean Engineering》 SCIE EI CSCD 2023年第5期794-806,共13页
Channel avulsion is a natural phenomenon that occurs abruptly on alluvial river deltas,which can affect the channel stability.The causes for avulsion could be generally categorized as topography-and flood-driven facto... Channel avulsion is a natural phenomenon that occurs abruptly on alluvial river deltas,which can affect the channel stability.The causes for avulsion could be generally categorized as topography-and flood-driven factors.However,previous studies on avulsion thresholds usually focused on topography-driven factors due to the centurial or millennial avulsion timescales of the world’s most deltas,but neglected the impacts of flood-driven factors.In the current study,a novel demarcation equation including the two driven factors was proposed,with the decadal timescale of avulsion being considered in the Yellow River Estuary(YRE).In order to quantify the contributions of different factors in each category,an entropy-based methodology was used to calculate the contributing weights of these factors.The factor with the highest weight in each category was then used to construct the demarcation equation,based on avulsion datasets associated with the YRE.An avulsion threshold was deduced according to the demarcation equation.This avulsion threshold was then applied to conduct the risk assessment of avulsion in the YRE.The results show that:two dominant factors cover respectively geomorphic coefficient representing the topography-driven factor and fluvial erosion intensity representing the flood-driven factor,which were thus employed to define a two dimensional mathematical space in which the demarcation equation can be obtained;the avulsion threshold derived from the equation was also applied in the risk assessment of avulsion;and the avulsion threshold proposed in this study is more accurate,as compared with the existing thresholds. 展开更多
关键词 avulsion threshold threshold conditions entropy weight method tail reach Yellow River Estuary
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Influence of climate change on hydrological process in the upper reaches of Shiyang River:A case study of the Xiying River,China
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作者 DongDong Qiu GuoFeng Zhu +7 位作者 Xi Zhao WenHao Zhang LiYuan Sang YuWei Liu XinRui Lin ZhuanXia Zhang ZhiGang Sun HuiYing Ma 《Research in Cold and Arid Regions》 CSCD 2023年第3期141-149,共9页
Climate change is the dominant factor affecting the hydrological process, it is of great significance to simulate and predict its influence on water resources management, socio-economic activities, and sustainable dev... Climate change is the dominant factor affecting the hydrological process, it is of great significance to simulate and predict its influence on water resources management, socio-economic activities, and sustainable development in the future. In this paper, the Xiying River Basin was taken as the study area, China Atmospheric Assimilation Driven Data Set(CMADS) and observation data from the Jiutiaoling station were used to simulate runoff of the SWAT model and calibrate and verify model parameters. On this basis, runoff change of the basin under the future climate scenario of CMIP6 was predicted. Our research shows that:(1) The contribution rates of climate change and human activities to runoff increase of the Xiying River are 89.17% and 10.83%, respectively. Climate change is the most important factor affecting runoff change of the Xiying River.(2) In these three different emission scenarios of SSP1-2.6, SSP2-4.5 and SSP5-8.5 in CMIP6 climate model, the average temperature increased by0.61, 1.09 and 1.74 C, respectively, in the Xiying River Basin from 2017 to 2050. Average precipitation increased by 14.36, 66.88, and 142.73 mm, respectively, and runoff increased by 15, 24, and 35 million m3, respectively.The effect of climate change on runoff will continue to deepen in the future. 展开更多
关键词 Upper reaches SWAT model Runoff simulation CMIP6 CanESM5
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Analysis of the Characteristics of the Low-level Jets in the Middle Reaches of the Yangtze River during the Mei-yu Season
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作者 Chunguang CUI Wen ZHOU +5 位作者 Hao YANG Xiaokang WANG Yi DENG Xiaofang WANG Guirong XU Jingyu WANG 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2023年第4期711-724,共14页
Here,we analyze the characteristics and the formation mechanisms of low-level jets(LLJs)in the middle reaches of the Yangtze River during the 2010 mei-yu season using Wuhan station radiosonde data and the fifth genera... Here,we analyze the characteristics and the formation mechanisms of low-level jets(LLJs)in the middle reaches of the Yangtze River during the 2010 mei-yu season using Wuhan station radiosonde data and the fifth generation of the European Centre for Medium-Range Weather Forecasts(ERA5)reanalysis dataset.Our results show that the vertical structure of LLJs is characterized by a predominance of boundary layer jets(BLJs)concentrated at heights of 900-1200 m.The BLJs occur most frequently at 2300 LST(LST=UTC+8 hours)but are strongest at 0200 LST,with composite wind velocities>14 m s^(-1).Synoptic-system-related LLJs(SLLJs)occur most frequently at 0800 LST but are strongest at 1100LST,with composite wind velocities>12 m s^(-1).Both BLJs and SLLJs are characterized by a southwesterly wind direction,although the wind direction of SLLJs is more westerly,and northeasterly SLLJs occur more frequently than northeasterly BLJs.When Wuhan is south of the mei-yu front,the westward extension of the northwest Pacific subtropical high intensifies,and the low-pressure system in the eastern Tibetan Plateau strengthens,favoring the formation of LLJs,which are closely related to precipitation.The wind speeds on rainstorm days are greater than those on LLJ days.Our analysis of four typical heavy precipitation events shows the presence of LLJs at the center of the precipitation and on its southern side before the onset of heavy precipitation.BLJs were shown to develop earlier than SLLJs. 展开更多
关键词 mei-yu front boundary layer jets synoptic low-level jets heavy rainfall middle reaches of the Yangtze River
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Research on Spatial Distribution of Settlements in the Upper Reaches of the Minjiang River
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作者 Lijun Song Shujun Tian +1 位作者 Lan Yang Na Fan 《Open Journal of Applied Sciences》 2023年第11期1967-1981,共15页
Under the background of the uplift of the Qinghai-Tibet Plateau, the settlements in the upper reaches of the Min River are significantly affected by the mountain environment, and their spatial distribution is typical ... Under the background of the uplift of the Qinghai-Tibet Plateau, the settlements in the upper reaches of the Min River are significantly affected by the mountain environment, and their spatial distribution is typical and representative. In this study, the relationship between settlements and topography, rivers and transportation, and the spatial distribution patterns of settlements, such as the aggregation and orientation characteristics of settlements, have been studied. The main conclusions include: 1) The settlement density decreases with the increase of elevation, slope, and distance from rivers and roads;76.25% and 63.17% of the settlements are distributed in the range of elevation 1500 - 3000 m and slope 6° - 25°, the upper reaches of the Min River are mostly alpine valley terrain, the bottom of the river has a low altitude, the landscape is undulating. The warm and humid climate is suitable for farming, conducive to agricultural production, and an ideal living environment for mountain residents. 2) The nuclear density of the settlement is distributed in strips along the axis of the river, and the closer to the river, the greater the nuclear density value. 3) Mathematical statistical methods were applied for the first time to realize the quantitative expression of the coupling of settlement and river direction. The influence of topographic conditions in different watersheds on the coupling degree of settlement extension and river flow direction was revealed. The slope of the fitted straight line between the settlement and river direction was 0.897, and the two directions were consistent. Except for the mainstream of the Min River, the larger values of the standard deviation ellipse flattening of settlements in each basin appeared in the upper reaches of the bay, and the overall trend showed a gradual decrease from the upstream to the downstream, which was consistent with the topographic change characteristics of the basin. 展开更多
关键词 Settlement Spatial Distribution AGGLOMERATION Alpine Valleys The Upper reaches of the Minjiang River
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基于环境DNA技术的珠江中下游鱼类多样性初步研究 被引量:1
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作者 朱书礼 陈蔚涛 +4 位作者 武智 夏雨果 杨计平 李跃飞 李捷 《南方水产科学》 CAS CSCD 北大核心 2024年第1期120-129,共10页
通过环境DNA技术(Environmental DNA,eDNA)检测珠江中下游鱼类生物多样性,探索珠江中下鱼类多样性监测和保护的新途径。2023年2月在珠江中下游设置了桂平、藤县、封开、德庆、肇庆和九江共6个采样点,通过水样采集及过滤、eDNA提取、遗... 通过环境DNA技术(Environmental DNA,eDNA)检测珠江中下游鱼类生物多样性,探索珠江中下鱼类多样性监测和保护的新途径。2023年2月在珠江中下游设置了桂平、藤县、封开、德庆、肇庆和九江共6个采样点,通过水样采集及过滤、eDNA提取、遗传标记扩增及测序和数据库比对分析等流程检测鱼类多样性。结果表明,6个采样点共检测出30种鱼类,隶属于4目10科27属,其中土著鱼类26种,外来种4种。较已有传统调查数据新检出2种鱼类:美丽沙鳅(Botia pulchra)和齐氏罗非鱼(Oceochromis zillii)。鱼类优势种为子陵吻鰕虎鱼(Rhinogobius giurinus)、瓦氏黄颡鱼(Pelteobagrus vachellii)、鲢(Hypophthalmichthys molitrix)、尼罗罗非鱼(O.nilotica)、齐氏罗非鱼、南方波鱼(Rasbora steineri)和鲤(Cyprinus carpio)。根据Shannon指数和Simpson指数显示,eDNA检测九江和桂平站点的鱼类多样性最高,藤县的最低。作为一种新的检测方法,eDNA技术可用于快速检测珠江中下游鱼类的多样性及分布,在实际应用中可将eDNA技术与传统的监测方法相结合,以提供更全面的鱼类生物多样性数据信息。 展开更多
关键词 环境DNA(eDNA) 鱼类多样性 珠江中下游
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长江中下游城市内涝与雨季污染协同治理对策 被引量:3
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作者 夏军 贾海峰 +2 位作者 张翔 张永勇 骆文广 《水资源保护》 EI CSCD 北大核心 2024年第1期1-5,15,共6页
针对长江中下游城市内涝与雨季污染协同治理的突出问题,对城市水安全、雨季水体返黑返臭风险和河湖水生态退化三方面存在的问题进行了论述。发现长江中下游城市河网密度高、降水量大、暴雨多发,同时人口密集、经济发展水平高,内涝、污... 针对长江中下游城市内涝与雨季污染协同治理的突出问题,对城市水安全、雨季水体返黑返臭风险和河湖水生态退化三方面存在的问题进行了论述。发现长江中下游城市河网密度高、降水量大、暴雨多发,同时人口密集、经济发展水平高,内涝、污染、生态退化等水问题突出;城市内涝频发,雨季污染造成某些城市水体局部返黑返臭,严重影响城市水环境品质,成为制约长江中下游城市绿色发展的重要瓶颈问题。提出了建立三级内涝协同防治体系、构建城市“绿-灰-蓝”设施耦合工程体系、协同推进水体品质提升与生态修复等建议。 展开更多
关键词 长中下游城市 城市内涝 雨季污染 协同治理 绿色发展
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初论黄河下游河道的河槽线 被引量:1
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作者 胡一三 曹常胜 夏修杰 《人民黄河》 CAS 北大核心 2024年第1期44-48,67,共6页
黄河白鹤镇至陶城铺河段两岸堤距宽,历史上河道冲淤变化迅速、河势游荡多变,经多年河道整治,总体上河势得到基本控制,滩槽逐步稳定。在此条件下,为促进黄河的生态保护和滩区发展,提高河道管理水平,将河道粗分为河槽与滩地,首次提出河槽... 黄河白鹤镇至陶城铺河段两岸堤距宽,历史上河道冲淤变化迅速、河势游荡多变,经多年河道整治,总体上河势得到基本控制,滩槽逐步稳定。在此条件下,为促进黄河的生态保护和滩区发展,提高河道管理水平,将河道粗分为河槽与滩地,首次提出河槽线的概念,明确了河槽线的含义及绘制河槽线的原则,强调绘制河槽线要以防洪安全为前提,给出了河槽线的绘制方法及其现场标示办法,分析了河槽线的作用等。 展开更多
关键词 河槽线 河道整治 黄河下游
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英语学习活动观视角下英文原版教材的评价与应用——以Reach Higher 3为例
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作者 赵王盼 《中国科技经济新闻数据库 教育》 2023年第3期133-136,共4页
教材是课程实施的主要载体,对教材进行深入地分析是教师有效教学的前提。在英语学习活动观理念下,教师需要学会整合教材内容,灵活使用教材,创设多种形式的活动,在活动中促进学生语英语学科核心素养的发展。本文旨在英语学习活动观理念... 教材是课程实施的主要载体,对教材进行深入地分析是教师有效教学的前提。在英语学习活动观理念下,教师需要学会整合教材内容,灵活使用教材,创设多种形式的活动,在活动中促进学生语英语学科核心素养的发展。本文旨在英语学习活动观理念的指导下分析评价Reach Higher 3英语教材,并结合实例给出其作为拓展教材的使用建议,为中小学英语教师设计教学活动,实践英语学习活动观提供参考。 展开更多
关键词 英语学习活动观 reach HIGHER 3教材 教材评价
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浑河清原流域地表水中多环芳烃污染特征及源解析 被引量:1
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作者 宋雪英 张慧钰 +4 位作者 庞琳 侯永侠 李玉双 赵晓旭 魏建兵 《沈阳大学学报(自然科学版)》 CAS 2024年第3期192-197,F0002,共7页
以浑河清原流域为对象,研究了16种多环芳烃(PAHs)化合物的质量浓度、组成、分布等污染特性,并利用特征比值法对其污染来源进行分析。研究结果表明:浑河上游清原段地表水中总PAHs质量浓度为176.49~4899.83 ng·L^(-1),总PAHs质量浓... 以浑河清原流域为对象,研究了16种多环芳烃(PAHs)化合物的质量浓度、组成、分布等污染特性,并利用特征比值法对其污染来源进行分析。研究结果表明:浑河上游清原段地表水中总PAHs质量浓度为176.49~4899.83 ng·L^(-1),总PAHs质量浓度平均值为953.51 ng·L^(-1);3环和4环PAHs为各采样点PAHs的主要组分;该流域PAHs污染的主要来源为生物质和煤的燃烧,这一结果与当地的生产生活实际相符。 展开更多
关键词 多环芳烃 分布 源解析 清原流域 浑河上游
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新安江模型敏感参数动态变化规律研究 被引量:1
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作者 石朋 丁松 +5 位作者 司伟 瞿思敏 吴洪石 肖豪 陆美霞 戈晓斌 《河海大学学报(自然科学版)》 CAS CSCD 北大核心 2024年第3期1-6,共6页
为了提高新安江模型在变化环境下的模拟精度,揭示模型参数动态变化规律,以淮河上游大坡岭流域为研究区构建分布式新安江模型,采用Spearman相关系数对比分析了模型敏感参数(KC、SM和CS)动态变化与环境因子(降水、气温和归一化植被指数)... 为了提高新安江模型在变化环境下的模拟精度,揭示模型参数动态变化规律,以淮河上游大坡岭流域为研究区构建分布式新安江模型,采用Spearman相关系数对比分析了模型敏感参数(KC、SM和CS)动态变化与环境因子(降水、气温和归一化植被指数)的变化关系,并建立了回归方程用于未来参数计算。结果表明:参数KC和SM的动态变化反映了研究区域的降水、气温和植被条件变化,而参数CS的动态变化仅反映了年降水总量变化;相较于静态参数,动态参数的模拟结果精度显著提高,径流深相对误差均值从21.3%降低到9.1%,纳什效率系数均值从0.75提高到0.81,动态参数比静态参数更适用于当前变化的环境。 展开更多
关键词 新安江模型 变化环境 动态参数 相关性分析 大坡岭流域 淮河上游
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基于水光电力系统时序生产模拟模型的水光优化配比研究 被引量:3
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作者 李继清 龙健 刘洋 《河海大学学报(自然科学版)》 CAS CSCD 北大核心 2024年第1期1-10,69,共11页
基于考虑系统负荷、新能源发电出力等时序变化特性的时序生产模拟法,建立了水光电力系统时序生产模拟模型;从系统结构性、经济性、灵活性与可靠性方面综合确定最佳水光容量配比,并通过金沙江上游川藏段水光系统验证了模型的合理性。金... 基于考虑系统负荷、新能源发电出力等时序变化特性的时序生产模拟法,建立了水光电力系统时序生产模拟模型;从系统结构性、经济性、灵活性与可靠性方面综合确定最佳水光容量配比,并通过金沙江上游川藏段水光系统验证了模型的合理性。金沙江上游川藏段光伏电站与水电站出力具有较好的年内、日内互补特性;对于2030年水平年,考虑枯期水电留存,913.6万kW水电配套400万kW光伏的方案综合性能更优,其新增非水可再生电量约60亿kW·h。 展开更多
关键词 水光互补特性 优化容量配比 时序生产模拟法 金沙江上游
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Thinking Out-of-Box in Addressing Communication and Service Delivery Challenges: Use of a Traditional Communication Method for Improving Immunization Coverage in Remote Rural Hard-to-Reach Areas of India
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作者 Iqbal Hossain Parthasarathi Ganguli +5 位作者 Chahat Narula Thakur Robert Steinglass Brian Castro Lora Shimp Saumen Bagchi Anita Bhargava 《World Journal of Vaccines》 CAS 2023年第1期1-12,共12页
Sirmaur district in the state of Himachal Pradesh in India is a hard-to-reach area situated in the western Himalayas having an extreme landscape with snow-laden mountains and extensive river systems that makes the del... Sirmaur district in the state of Himachal Pradesh in India is a hard-to-reach area situated in the western Himalayas having an extreme landscape with snow-laden mountains and extensive river systems that makes the delivery of immunization services extremely challenging. Vaccinators needed a long walk through the hilly terrain to reach outreach sites. Community mobilizers were unable to go house to house to inform the caregivers to bring children to the site for vaccination. Caregivers were unaware when the vaccinators arrive at the site. As a result, many children missed vaccination or were not vaccinated timely. Age-appropriate vaccination coverage (according to national immunization schedule) in the Sirmaur district was the lowest in the state. Thinking out-of-box to address the communication barriers with the caregivers, the traditional drum beating was used, for the first time in India, in two blocks of the Sirmaur district (Rajpura and Shillai). The initiative was planned and implemented by the district health system with the support of the local community leaders. An exit interview was conducted to know the reach of the drum beating to caregivers, and a baseline and end line household survey was conducted to know the outcome of the initiative on age-appropriate vaccination coverage. Analysis of exit interviews data indicated a very high reach of a drum beating to the caregivers;more than 97% of caregivers in Rajpura and 100% in Shillai heard drum beating, and almost 95% of caregivers in Rajpura and 98% in Shillai knew the purpose of drum beating. Analysis of immunization data from baseline and end line surveys showed improvement in age-appropriate vaccination coverage for all vaccines in Rajpura (by 2.2% for BCG, 15.3% for Pentavalent 1, 14.9% for Pentavalent 2, 14.1% for Pentavalent 3, and 6.5% for Measles/MR). In Shillai, age-appropriate vaccination coverage improved for Pentavalent 1 (by 3.4%), Pentavalent 2 (by 5%) and Measles/MR (by 1.7%). In addition, dropout rates were reduced in both the blocks, particularly in Rajpura Pentavalent 1 to Measles dropout rate was reduced by 13.5%. Both health workers and community leaders had positive perceptions of the drum beating initiative. However, another important lesson learned from the initiative was that both the access and demand-side barriers need to be addressed for the desired improvement of age-appropriate immunization coverage. In Shillai, there was lower coverage improvement and a reduction in dropout rates attributed to vacant positions of vaccinators that caused an issue with access to immunization services to people. 展开更多
关键词 IMMUNIZATION Hard-to-reach Area COMMUNICATION Age-Appropriate Vaccination Coverage
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