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Review of Restoration Technology and Multi-environmental Factors Analysis of West Lake Ecosystem in Hangzhou City
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作者 Wang Xin Zhao Congcong Liu Yang 《Journal of Northeast Agricultural University(English Edition)》 CAS 2022年第3期37-47,共11页
The urban lake ecosystem has the characteristics of long-term,complex and comprehensive in its ecological restoration process because it is related to social and economic activities at multiple levels.Located in Hangz... The urban lake ecosystem has the characteristics of long-term,complex and comprehensive in its ecological restoration process because it is related to social and economic activities at multiple levels.Located in Hangzhou City,China,the West Lake is a national-level scenic spot and a world heritage cultural landscape.It provides key ecosystem services for the city and has a significant impact on the urban ecological environment and the well-being of citizens.The West Lake has undergone an 1800-year governance process in history,realizing the harmonious coexistence with Hangzhou City.Since modern times,due to the rapid development of urbanization and industrialization,the water quality of the West Lake and its freshwater ecosystem have been greatly damaged.Since 2002,Hangzhou City has achieved the overall restoration of the West Lake ecosystem through a series of measures,such as water diversion projects,dredging projects,and the West Lake comprehensive protection project,and the water environment and lakeshore landscape have been greatly improved.This study analyzed the restoration technology of the West Lake ecosystem from two scales of the watershed and the site and discussed the water ecological governance system of the West Lake in the past 20 years.Through thedata analyses of the West Lake land use,vegetation,TP,TN,NH_(3)-N,COD_(Mn) and other multi-environmental factors,the results showed that the water quality,transparency and eutrophication of the West Lake had been greatly improved.At the same time,the application of large-scale restoration methods and technologies also required long-term observation,and attention should be paid to the proliferation of alien species and the loss of heritage value,so as to further avoid potential ecological risks caused by ecological restoration. 展开更多
关键词 urban lake aquatic ecosystem ecological restoration technology comprehensive environmental protection project
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Expression of transcription factors in polycystic ovary syndrome
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作者 ZHANG Qi ZHU Shujuan JIANG Bin 《中南大学学报(医学版)》 北大核心 2025年第3期447-456,共10页
Objective:Polycystic ovary syndrome(PCOS)is a common endocrine disorder that affects women’s health.This study aims to investigate gene and transcription factor(TF)expression differences between PCOS patients and hea... Objective:Polycystic ovary syndrome(PCOS)is a common endocrine disorder that affects women’s health.This study aims to investigate gene and transcription factor(TF)expression differences between PCOS patients and healthy individuals using bioinformatics approaches,and to verify the function of key transcription factors,with the goal of providing new insights into the pathogenesis of PCOS.Methods:Differentially expressed genes(DEGs)and differentially expressed transcription factors(DETFs)between PCOS patients and controls were identified from the RNA sequencing dataset GSE168404 using bioinformatics methods.Functional enrichment analysis was performed using Gene Ontology(GO)and Kyoto Encyclopedia of Genes and Genomes(KEGG)databases.The expression and function of core transcription factors were further validated in ovarian tissues of PCOS model mice and control mice using Western blotting and reverse transcription quantitative polymerase chain reaction(RTqPCR).Results:A total of 332 DEGs were identified between PCOS patients and controls,including 259 upregulated and 73 downregulated genes in the PCOS group.19 DETFs were further screened,of which 16 were upregulated and 3 were downregulated in PCOS.The upregulated DETFs(including TFCP2L1,DACH1,ESR2,AFF3,SMAD9,ZNF331,HOPX,ATOH8,HIF3α,DPF3,HOXC4,HES1,ID1,JDP2,SOX4,and ID3)were primarily associated with lipid metabolism,development,and cell adhesion.Protein and mRNA expression analysis in PCOS model mice revealed significantly decreased levels of hypoxia-inducible factor(HIF)1αand HIF2α,and significantly increased expression of HIF3αcompared to control mice(all P<0.001).Conclusion:Significant differences in gene and TF expression exist between PCOS patients and healthy individuals.HIF-3αmay play a crucial role in PCOS and could serve as a novel biomarker for diagnosis and a potential therapeutic target. 展开更多
关键词 polycystic ovary syndrome transcription factor hypoxia-inducible factors regulatory networks BIOINFORMATICS
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Braven Environmental公司将向BASF公司供应先进的再生原料
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作者 程钰丹(摘译) 《石油炼制与化工》 北大核心 2025年第6期99-99,共1页
BASF公司与化学回收公司Braven Environmental签署了Braven PyChem热解油的供应协议。该热解油来自混合废塑料,将部分替代BASF TotalEnergies石化公司(BTP)位于德克萨斯州亚瑟港工厂的化石基进料。Braven Environmental公司宣布将在德... BASF公司与化学回收公司Braven Environmental签署了Braven PyChem热解油的供应协议。该热解油来自混合废塑料,将部分替代BASF TotalEnergies石化公司(BTP)位于德克萨斯州亚瑟港工厂的化石基进料。Braven Environmental公司宣布将在德克萨斯州特克萨卡纳建设含多单元装置的热解油工厂,根据协议,向BASF公司供应该工厂产出的热解油。Braven PyChem热解油已获得ISCC PLUS认证,采用Braven专有的热解技术生产,原料来自本该送往垃圾填埋场和焚烧场的废塑料。 展开更多
关键词 热解油 Braven PyChem BASF公司 Braven environmental
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Study on the phytoplankton community structure and its driving factors in Furong Creek during spring and autumn under the influence of cascade weirs
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作者 REN Jiangshan YU Jun +2 位作者 LI Jingjuan LYU Jianzhang WANG Xiaogang 《水利水电技术(中英文)》 北大核心 2025年第3期171-185,共15页
[Objective]The construction of weirs changes the hydraulic characteristics of rivers and affects the structure of phytoplankton communities and the health of aquatic ecosystems in the river.This study aims to explore ... [Objective]The construction of weirs changes the hydraulic characteristics of rivers and affects the structure of phytoplankton communities and the health of aquatic ecosystems in the river.This study aims to explore the nonlinear response relationship between phytoplankton community structure and its driving factors in spring and autumn in Furong Creek under the construction of cascade weirs.[Methods]The structure of phytoplankton communities and related environmental factors were investigated in Furong Creek from 2023 to 2024.This study focused on the analysis of the changes of nutrient concentrations and biomass of phytoplankton in autumn and spring within the same dry season in Furong Creek.Redundancy analysis was used to identify the key factors influencing the structure of phytoplankton communities.The MIKE 11 model was employed to simulate the hydrodynamic changes in the river.Combined with total nitrogen and permanganate index,a GAM model of phytoplankton diversity index and hydrodynamic factors was developed,and the change of phytoplankton diversity after the optimized layout of the cascade weirs was fitted.[Results]The result showed that the annual average value of Shannon-Wiener diversity index of phytoplankton in Furong Creek was 2.79,which was in a state of mild pollution.A total of 239 species from 95 genera in 8 phyla were identified.Among the phytoplankton,Chlorophyta was the dominant group throughout the year in Furong Creek,followed by Bacillariophyta and Cyanophyta.The cell abundance of phytoplankton ranged from 3.11 to 20.64 mg/L and from 0.23 to 6.31 mg/L in spring and autumn,which indicated a clear seasonal succession of phytoplankton community structure.Compared with autumn,the relative abundance of Cyanophyta significantly decreased in spring across the whole river section,while Chrysophyta and Dinophyta showed significant increase at some monitoring sites,leading to water bloom phenomenon and a noticeable decline in the diversity of phytoplankton.The dominant species in the water bodies throughout the year were Cyclotella catenata,Chlorella vulgaris,Scenedesmus bijuga,Scenedesmus quadricauda,Chroomonas acuta,Cryptomonas ovata,and Cryptomonas erosa.Redundancy analysis(RDA)showed that hydrodynamic factors(v,h)and water environmental factors(TN,COD_(Mn))were the main influencing factors of phytoplankton community structure.[Conclusion]The result show that the nutrient concentration,phytoplankton biomass,and density in Furong Creek in spring are significantly higher than in autumn.The GAM model,constructed by combining hydrodynamic and environmental factors,can effectively reflect the nonlinear relationship between phytoplankton diversity index and its driving factors.In spring,with an increase in nutrient concentration,the habitat conditions of low flow speed and high water depths formed by overflow weirs will lead to a decrease in the Shannon-Wiener index of phytoplankton and an intensified risk of eutrophication.However,a reasonable layout scheme of cascade weirs will improve the diversity of phytoplankton and reduce the risk of eutrophication in the river.The findings of this study can help deepen the understanding of the ecological and environmental effects of cascade weir construction in the river. 展开更多
关键词 cascade weirs MIKE 11 model redundancy analysis GAM model influencing factors
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海岸带地下水循环及其环境效应研究进展与展望
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作者 韩冬梅 曹国亮 +1 位作者 萧怡 宋献方 《地学前缘》 北大核心 2026年第1期384-404,共21页
海岸带地下水循环是陆海交互带水动力过程与生态环境演化的关键环节,其动态演变受自然与人类活动的双重驱动,并对沿海地区的资源、生态与可持续发展产生深远影响。本文系统综述了滨海地下水循环及其环境效应的研究进展,重点探讨了以下内... 海岸带地下水循环是陆海交互带水动力过程与生态环境演化的关键环节,其动态演变受自然与人类活动的双重驱动,并对沿海地区的资源、生态与可持续发展产生深远影响。本文系统综述了滨海地下水循环及其环境效应的研究进展,重点探讨了以下内容:海岸带水循环的多尺度过程,包括地表水地下水相互作用、潮汐驱动下的地下水流动态及陆海界面水文交换;地下水循环演变的驱动要素,涵盖气候变化(包括降水格局改变、海平面上升)、人类活动(包括人口经济增长、土地利用变化、流域水资源开发)以及地质地貌的控水机制;地下水文过程引发的环境效应,包括营养物质与污染物迁移对近岸水质的调控、海水入侵与土壤盐渍化的生态威胁、海底地下水排泄(SGD)对海洋碳\\氮循环的贡献,以及超采引发的地面沉降灾害;阐释了我国海岸带相关的环境效应特征。提出未来研究应加强高分辨率监测、多过程耦合模拟、人地系统协同管理与碳中和背景下的生态效应评估,支撑海岸带水资源安全保障与生态保护战略实施。 展开更多
关键词 海岸带 地下水循环 海水入侵 海底地下水排泄 环境效应 海岸带管理
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1990-2021年中国肺癌发病和死亡趋势分析及2035年预测研究
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作者 杨清惠 胡映雪 +1 位作者 倪萍蔚 刘晓 《中国全科医学》 北大核心 2026年第2期256-263,共8页
背景肺癌是全球重大公共卫生问题,中国作为肺癌负担较重的国家之一,其发病与死亡趋势受环境、经济及行为因素的多重影响,且存在显著区域异质性。解析肺癌疾病负担的时空驱动机制并提出精准防控策略,对实现“健康中国2030”目标至关重要... 背景肺癌是全球重大公共卫生问题,中国作为肺癌负担较重的国家之一,其发病与死亡趋势受环境、经济及行为因素的多重影响,且存在显著区域异质性。解析肺癌疾病负担的时空驱动机制并提出精准防控策略,对实现“健康中国2030”目标至关重要。目的分析并预测1990—2021年中国肺癌发病并死亡趋势,探讨区域环境与经济因素对肺癌流行趋势的空间异质性影响,提出精准防控建议。方法基于全球疾病负担(GBD)数据,提取中国1990—2021年不同性别、年龄的肺癌发病和死亡人数、年龄标化发病率及年龄标化死亡率数据。采用年龄-时期-队列模型、联结点回归(JPR)模型及Holt指数平滑模型识别趋势转折点;整合环境(PM_(2.5)、工业污染)、经济(人均GDP、医疗资源)数据,利用空间杜宾模型解析区域异质性;通过Holt指数平滑模型预测2035年肺癌发病与死亡趋势。结果JPR模型显示1990—2021年中国肺癌年龄标化发病率年均增长0.94%(95%CI=0.87%~1.01%),年龄标化死亡率增长0.38%(95%CI=0.31%~0.45%);肺癌发病率呈现空间聚集性(P<0.05),京津冀、黑吉辽及四川省为高风险地区。空间杜宾模型显示,PM_(2.5)暴露(β=1.15,95%CI=1.02~1.28)、工业废气排放量大(β=0.89,95%CI=0.75~1.03)是肺癌发病的危险因素(P<0.05),而人均GDP高(β=-0.62,95%CI=-0.78~-0.46)和三级医院密度高(β=-0.74,95%CI=-0.89~-0.59)是肺癌发病的保护因素(P<0.05)。预测到2035年,全国肺癌年龄标化发病率将达46.18/10万,年龄标化死亡率将达到38.26/10万,2022—2035年女性的肺癌发病和死亡趋势可能进一步上升,而男性的变化趋势较为平缓。结论中国肺癌疾病负担呈现“北高南低”的空间分异特征,环境暴露与医疗资源不均是关键驱动因素。建议针对高风险区域(北方工业区)及人群(女性患者)实施精准筛查,以降低健康不平等,助力国家癌症防控目标实现。 展开更多
关键词 肺癌 发病趋势 死亡趋势 环境暴露 高风险亚群 精准防控
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Ranking environmental projects model based on multicriteria decision-making and the weight sensitivity analysis 被引量:5
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作者 Jiang Yan Tian Dagang Pan Yue 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2007年第3期534-539,共6页
With the fast growth of Chinese economic, more and more capital will be invested in environmental projects. How to select the environmental investment projects (alternatives) for obtaining the best environmental qua... With the fast growth of Chinese economic, more and more capital will be invested in environmental projects. How to select the environmental investment projects (alternatives) for obtaining the best environmental quality and economic benefits is an important problem for the decision makers. The purpose of this paper is to develop a decision-making model to rank a finite number of alternatives with several and sometimes conflicting criteria. A model for ranking the projects of municipal sewage treatment plants is proposed by using exports' information and the data of the real projects. And, the ranking result is given based on the PROMETHEE method. Furthermore, by means of the concept of the weight stability intervals (WSI), the sensitivity of the ranking results to the size of criteria values and the change of weights value of criteria are discussed. The result shows that some criteria, such as “proportion of benefit to project cost”, will influence the ranking result of alternatives very strong while others not. The influence are not only from the value of criterion but also from the changing the weight of criterion. So, some criteria such as “proportion of benefit to project cost” are key critera for ranking the projects. Decision makers must be cautious to them. 展开更多
关键词 multicriteria decision-making ranking environmental projects model PROMETHEE method sensitivity analysis weight stability intervals.
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Ecological environmental quality evaluation and driving factor analysis of the Lijiang River Basin,based on Google Earth Engine 被引量:2
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作者 WEI Xi YANG Dazhi +2 位作者 CAI Xiangwen SHAO Ya TANG Xiangling 《中国生态农业学报(中英文)》 CAS CSCD 北大核心 2024年第9期1592-1608,共17页
For regional ecological management,it is important to evaluate the quality of ecosystems and analyze the underlying causes of ecological changes.Using the Google Earth Engine(GEE)platform,the remote sensing ecological... For regional ecological management,it is important to evaluate the quality of ecosystems and analyze the underlying causes of ecological changes.Using the Google Earth Engine(GEE)platform,the remote sensing ecological index(RSEI)was calculated for the Lijiang River Basin in Guangxi Zhuang Autonomous Region for 1991,2001,2011,and 2021.Spatial autocorrelation analysis was employed to investigate spatiotemporal variations in the ecological environmental quality of the Lijiang River Basin.Furthermore,geographic detectors were used to quantitatively analyze influencing factors and their interaction effects on ecological environmental quality.The results verified that:1)From 1991 to 2021,the ecological environmental quality of the Lijiang River Basin demonstrated significant improvement.The area with good and excellent ecological environmental quality in proportion increased by 19.69%(3406.57 km^(2)),while the area with fair and poor ecological environmental quality in proportion decreased by 10.76%(1860.36 km^(2)).2)Spatially,the ecological environmental quality of the Lijiang River Basin exhibited a pattern of low quality in the central region and high quality in the periphery.Specifically,poor ecological environmental quality characterized the Guilin urban area,Pingle County,and Lingchuan County.3)From 1991 to 2021,a significant positive spatial correlation was observed in ecological environmental quality of the Lijiang River Basin.Areas with high-high agglomeration were predominantly forests and grasslands,indicating good ecological environmental quality,whereas areas with low-low agglomeration were dominated by cultivated land and construction land,indicating poor ecological environmental quality.4)Annual average precipitation and temperature exerted the most significant influence on the ecological environmental quality of the basin,and their interactions with other factors had the great influence.This study aimed to enhance understanding of the evolution of the ecological environment in the Lijiang River Basin of Guangxi Zhuang Autonomous Region and provide scientific guidance for decision-making and management related to ecology in the region. 展开更多
关键词 Ecological environmental quality Remote sensing ecological index Driving factor Google Earth Engine Lijiang River Basin
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Directly searching method for slip plane and its influential factors based on critical state of slope 被引量:30
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作者 林杭 曹平 +2 位作者 宫凤强 李江腾 桂易林 《Journal of Central South University》 SCIE EI CAS 2009年第1期131-135,共5页
In order to determine the slip plane of slope directly by the calculation results of strength reduction method, and analyze the influential factors of slope stability, a numerical model was established in plane strain... In order to determine the slip plane of slope directly by the calculation results of strength reduction method, and analyze the influential factors of slope stability, a numerical model was established in plane strain mode by FLAC3D for homogeneous soil slope, whose parameters were reduced until the slope reached the critical state. Then FISH program was used to get the location data of slip plane from displacement contour lines. Furthermore, the method to determine multiple slip planes was also proposed by setting different heights of elastic areas. The influential factors for the stability were analyzed, including cohesion, internal friction angle, and tensile strength. The calculation results show that with the increase of cohesion, failure mode of slope changes from shallow slipping to the deep slipping, while inclination of slip plane becomes slower and slipping volume becomes larger; with the increase of friction angle, failure mode of slope changes from deep slipping to shallow slipping, while slip plane becomes steeper and upper border of slip plane comes closer to the vertex of slope; the safety factor increases little and slip plane goes far away from vertex of slope with the increase of tensile strength. 展开更多
关键词 SLOPE strength reduction slip plane STABILITY influential factors
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Family-relatedFactorsThatInfluenceChildren’sAcademicAchievementsinSchool
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作者 何献忠 《陕西师范大学学报(哲学社会科学版)》 CSSCI 北大核心 2002年第S1期323-328,共6页
This essay studies various family-related factors that influence a child’s academic achievement in school in P.R. China. The factors are illustrated under three categories: the family’s social class and education, e... This essay studies various family-related factors that influence a child’s academic achievement in school in P.R. China. The factors are illustrated under three categories: the family’s social class and education, early home environment and family material condition. The author discusses the relevant factors by way of relating the knowledge of social environment to his own experiences as a student and then teacher in China. The essay closes with a discussion directing the public’s attention to the concern about home-related factors influencing a child’s academic achievements in school. 展开更多
关键词 family related factors childrens academic achievements home environment material condition
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不同培育方式朝鲜淫羊藿品质及土壤特性
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作者 侯会玲 李涵冰 +3 位作者 李艳霞 向光亿 张永刚 李晓宇 《东北林业大学学报》 北大核心 2026年第1期110-117,共8页
探究不同培育方式对朝鲜淫羊藿(Epimedium koreanum Nakai)品质的影响,并分析其与根际土壤特性之间的相关性,以丰富其生态种植理论,为高品质栽培技术提供科学依据。以野生抚育(WT)、林下仿生栽培(FP)和拟境栽培(SC)3种培育方式的朝鲜淫... 探究不同培育方式对朝鲜淫羊藿(Epimedium koreanum Nakai)品质的影响,并分析其与根际土壤特性之间的相关性,以丰富其生态种植理论,为高品质栽培技术提供科学依据。以野生抚育(WT)、林下仿生栽培(FP)和拟境栽培(SC)3种培育方式的朝鲜淫羊藿为对象,比较分析朝鲜淫羊藿品质、根际土壤理化性质及酶活性的动态变化和相互关系。结果表明:黄酮醇苷类及总黄酮等活性成分的质量分数由大到小总体表现为SC、FP、WT,且在7月下旬至8月下旬期间积累趋于稳定。相关性分析显示,土壤全钾与活性成分质量分数呈极显著正相关(P<0.01),速效磷与朝藿定B、总黄酮醇苷呈正相关(P<0.05);而有机质、全氮及土壤酶活性则与活性成分呈显著负相关(P<0.05)。综合实际生产效益,建议推广林下仿生栽培模式,并在土壤管理过程中采取“控氮、增磷钾”的施肥策略。 展开更多
关键词 朝鲜淫羊藿 培育方式 药材质量 土壤因子
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Near ground wind characteristics during typhoon Meari:Turbulence intensities, gust factors, and peak factors 被引量:1
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作者 WANG Xu HUANG Peng +1 位作者 YU Xian-feng HUANG Chao 《Journal of Central South University》 SCIE EI CAS CSCD 2017年第10期2421-2430,共10页
Wind data were collected during the 2011 typhoon Meari at heights of 10, 20, 30, and 40 m above the ground using a 40 m high anemometer tower in the coastal area near Shanghai Pudong International Airport. Wind speeds... Wind data were collected during the 2011 typhoon Meari at heights of 10, 20, 30, and 40 m above the ground using a 40 m high anemometer tower in the coastal area near Shanghai Pudong International Airport. Wind speeds and directions, turbulence intensities, gust factors, and peaks were analyzed using the time records of wind speed. The results show that turbulence intensity components in longitudinal, lateral, and vertical directions decrease with mean wind speed, regardless of elevations, and the turbulence intensities are in a linear relationship with mean wind speeds. The ratios of three turbulence intensity components(i.e. Iu, Iv, Iw) at heights of 10, 20 and 40 m were calculated and equal to be 1:0.88:0.50, 1:0.84:0.57, and 1:0.9:0.49, respectively. In addition, the gust factors in three directions exhibit a reduction with increasing mean wind speed. The peak factors at different heights show a similar trend and slightly decrease with mean wind speed; average peak factors for all 10-min data from Typhoon Meari are 2.43, 2.48, and 2.47, respectively. 展开更多
关键词 TYPHOON Meari wind characteristics TURBULENCE intensity GUST FACTOR peak FACTOR
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Actuality and Influencing Factors of Integrated Production Capacity of Foodstuff in Heilongjiang Province 被引量:4
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作者 Zhou Hui-qiu Zhang De-hua 《Journal of Northeast Agricultural University(English Edition)》 CAS 2012年第1期82-90,共9页
Heilongjiang Province is an important marketable grain depot in China. Since the reform and opening up, Heilongjiang Province production capacity of foodstuff is increasingly growing into a new level. This paper start... Heilongjiang Province is an important marketable grain depot in China. Since the reform and opening up, Heilongjiang Province production capacity of foodstuff is increasingly growing into a new level. This paper started with the actuality of Heilongjiang Province integrated production capacity of foodstuff, and analyzed its major factors empirically through the mathematical model, then proposed some measures to enhance Heilongjiang Province production capacity of foodstuff which ensured China foodstuff security 展开更多
关键词 Heilongjiang Province integrated foodstuff production capacity influencing factor
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Spatial distribution and environmental characterization of sediment-associated metals from middle-downstream of Xiangjiang River,southern China 被引量:9
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作者 郭朝晖 宋杰 +3 位作者 肖细元 明辉 苗旭锋 王凤永 《Journal of Central South University》 SCIE EI CAS 2010年第1期68-78,共11页
The contamination and environmental risk assessment of the toxic elements in sediments from the middle-downstream (Zhuzhou-Changsha section) of the Xiangjiang River in Hunan Province of China were studied. The results... The contamination and environmental risk assessment of the toxic elements in sediments from the middle-downstream (Zhuzhou-Changsha section) of the Xiangjiang River in Hunan Province of China were studied. The results show that As, Cd, Pb and Zn are major contaminants in sediments, and average concentrations of these elements significantly exceed both the Control Standards for Pollutants in Sludge of China (GB4284-84) for agricultural use in acidic soils and the effect range median (ERM) values. The average concentrations of As, Cd and Pb in the river water slightly exceed the limit of Surface Water Environment Quality Standard (GB3838-2002). The concentrations of As and Cr in depth profiles extensively change, but slight changes are observed in Pb and Zn. Cd and Zn in most sediment samples can easily enter the food-chain and bring possible ecotoxicological risk to organisms living in sediments according to the risk assessment code. 展开更多
关键词 SEDIMENT toxic elements spatial distribution environmental risk Xiangjiang River
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New weighting factors assignment of evidence theorybased one vidence distance 被引量:3
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作者 ChenLiangzhou ShiWenkang DuFeng 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2005年第2期273-278,共6页
Evidence theory has been widely used in the information fusion for its effectiveness of the uncertainty reasoning. However, the classical DS evidence theory involves counter-intuitive behaviors when the high conflict ... Evidence theory has been widely used in the information fusion for its effectiveness of the uncertainty reasoning. However, the classical DS evidence theory involves counter-intuitive behaviors when the high conflict information exists. Based on the analysis of some modified methods, Assigning the weighting factors according to the intrinsic characteristics of the existing evidence sources is proposed, which is determined on the evidence distance theory. From the numerical examples, the proposed method provides a reasonable result with good convergence efficiency. In addition, the new rule retrieves to the Yager's formula when all the evidence sources contradict to each other completely. 展开更多
关键词 evidence theory rule of combination weighting factors evidence distance.
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The Positive Role of Governance in the Way Environmental Policies Impact Technological Innovation 被引量:1
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作者 Li Shiqi 《学术界》 CSSCI 北大核心 2018年第2期271-282,共12页
Against the backdrop of the knowledge economy, global economy is goingthrough a major transformation. How to alleviate the pressure of resources and the environ-ment and to achieve the sustainable development of the e... Against the backdrop of the knowledge economy, global economy is goingthrough a major transformation. How to alleviate the pressure of resources and the environ-ment and to achieve the sustainable development of the economy has become a global agenda.China' s economy growth has been rapid for decades since the reform and opening up policy,but this has also been a great drain on China' s resources and the environment, which is an ur-gent problem to tackle. In recently years, the Chinese government has launched many environ-mental policies in the hope of encouraging technological innovation to guarantee the sustain-able development of the economy. However, research suggested that technological innovationis negatively correlated with environmental policies in most scenarios. In some cases, the num-ber of technological innovation decreases after policies take effect and increases after a whilelike a U - curve. In order to solve this problem, I decided to analyze the panel data from 80provinces in China between 2008 and 2014 and conclude that local governance can implementenvironmental regulations while having a positive impact on the technological innovation inenterprises. In the conclusion, suggestions are given to local governments on how to better en-force environmental policies. 展开更多
关键词 environmental POLICIES TECHNOLOGICAL innovation GOVERNANCE
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Effects of fundamental factors on coupled vibration of wind-rail vehicle-bridge system for long-span cable-stayed bridge 被引量:11
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作者 张明金 李永乐 汪斌 《Journal of Central South University》 SCIE EI CAS CSCD 2016年第5期1264-1272,共9页
In a wind-vehicle-bridge(WVB) system,there are various interactions among wind,vehicle and bridge.The mechanism for coupling vibration of wind-vehicle-bridge systems is explored to demonstrate the effects of fundament... In a wind-vehicle-bridge(WVB) system,there are various interactions among wind,vehicle and bridge.The mechanism for coupling vibration of wind-vehicle-bridge systems is explored to demonstrate the effects of fundamental factors,such as mean wind,fluctuating wind,buffeting,rail irregularities,light rail vehicle vibration and bridge stiffness.A long cable-stayed bridge which carries light rail traffic is regarded as a numerical example.Firstly,a finite element model is built for the long cable-stayed bridge.The deck can generally be idealized as three-dimensional spine beam while cables are modeled as truss elements.Vehicles are modeled as mass-spring-damper systems.Rail irregularities and wind fluctuation are simulated in time domain by spectrum representation method.Then,aerodynamic loads on vehicle and bridge deck are measured by section model wind tunnel tests.Eight vertical and torsional flutter derivatives of bridge deck are identified by weighting ensemble least-square method.Finally,dynamic responses of the WVB system are analyzed in a series of cases.The results show that the accelerations of the vehicle are excited by the fluctuating wind and the track irregularity to a great extent.The transverse forces of wheel axles mainly depend on the track irregularity.The displacements of the bridge are predominantly determined by the mean wind and restricted by its stiffness.And the accelerations of the bridge are enlarged after adding the fluctuating wind. 展开更多
关键词 wind-vehicle-bridge system coupled vibration long-span cable-stayed bridge fundamental factors
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新疆阿勒泰地区农牧区人群“生命八要素”评分与高血压患病风险的横断面研究
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作者 陈玉斐 赵倩 +4 位作者 谢依热·哈木拉提 蔡丽婷 李晓梅 杨毅宁 刘芬 《中国全科医学》 北大核心 2026年第1期91-99,共9页
背景高血压是主要的心血管疾病,“生命八要素”(LE8)评分作为近期提出的心血管健康评价指标,与高血压患病风险之间的关系尚不明确。目的探讨新疆阿勒泰地区农牧区人群LE8评分与高血压患病风险之间的关系。方法于2023年10—11月,依据人... 背景高血压是主要的心血管疾病,“生命八要素”(LE8)评分作为近期提出的心血管健康评价指标,与高血压患病风险之间的关系尚不明确。目的探讨新疆阿勒泰地区农牧区人群LE8评分与高血压患病风险之间的关系。方法于2023年10—11月,依据人口规模成比例系统抽样(PPS)在新疆阿勒泰地区抽取27个自然村,在纳入的自然村中招募符合研究要求的居民进行问卷调查、体格检查及实验室指标检测。LE8评分包括4个健康行为(饮食、体力活动、尼古丁暴露、睡眠)和4个健康因素(BMI、血脂、血糖、血压),本研究以除血压外的其余7个组分计算LE8评分。LE8评分、健康行为和健康因素子量表评分、7个组分评分均被划分为3组:低分组(0~49分)、中等分组(50~79分)及高分组(80~100分)。采用限制性立方样条图绘制LE8评分与高血压患病的剂量-反应曲线,采用Logistic回归模型分析LE8评分对高血压患病的影响。结果本研究共纳入2872名居民,检出高血压患者1540名,高血压粗患病率为53.62%,标准化患病率为34.64%。其中,男性高血压患病率为61.13%(766/1253),女性高血压患病率为47.81%(774/1619),男性高血压患病率高于女性(P<0.05)。是否患高血压居民的LE8评分比较,差异有统计学意义(P<0.05)。在调整混杂因素后,与低分组比较,LE8评分、健康因素评分中等分组和高分组的高血压患病风险降低(P<0.05),且每增加10分,高血压患病风险分别降低24.3%和41.8%(P<0.05)。LE8评分与高血压患病风险之间存在明显非线性关系(P_(非线性)=0.010),健康因素评分与高血压患病之间呈线性关系(P_(非线性)=0.637),未发现健康行为评分与高血压患病之间的明显关联(P>0.05)。BMI、血糖水平、体力活动评分高分组的高血压患病风险较低分组低(P<0.05)。LE8评分与年龄在高血压患病中存在交互作用(P_(交互)<0.05),对于50岁以上的人群,LE8评分对降低高血压患病风险的作用更加明显(P<0.05)。结论LE8评分与高血压患病风险呈非线性相关,保持较高的LE8评分可降低高血压疾病负担。 展开更多
关键词 生命八要素评分 高血压 农牧区人群 健康行为 健康因素 横断面研究
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Influences of nonassociated flow rules on seismic bearing capacity factors of strip footing on soil slope by energy dissipation method 被引量:15
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作者 杨小礼 郭乃正 +1 位作者 赵炼恒 邹金锋 《Journal of Central South University of Technology》 EI 2007年第6期842-847,共6页
Seismic bearing capacity factors of a strip footing placed on soil slope were determined with both associated and nonassociated flow rules. Quasi-static representation of earthquake effects using a seismic coefficient... Seismic bearing capacity factors of a strip footing placed on soil slope were determined with both associated and nonassociated flow rules. Quasi-static representation of earthquake effects using a seismic coefficient concept was adopted for seismic bearing capacity calculations. A multi-wedge translational failure mechanism was used to obtain the seismic bearing capacity factors for different seismic coefficients and various inclined angles. Employing the associated flow rule, numerical results were compared with the published solutions. For bearing capacity factors related to cohesion and equivalent surcharge load, the maximum difference approximates 0.1%. However, the difference of bearing capacity factor related to unit weight is larger. With the two flow rules, the seismic bearing capacity factors were presented in the form of design charts for practical use. The results show that seismic bearing capacity factors related to the cohesion, the equivalent surcharge load and the unit weight increase greatly as the dilatancy angle increases, and that the nonassociated flow rule has important influences on the seismic bearing capacity. 展开更多
关键词 nonassociated flow rule seismic bearing capacity factor EARTHQUAKE
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Environmental impact evaluation for high-speed railway 被引量:4
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作者 宋晓东 付延冰 +1 位作者 陈治亚 刘恒斌 《Journal of Central South University》 SCIE EI CAS 2014年第6期2366-2371,共6页
Environmental impact evaluation system boundary of high-speed railway was defined based on the total life cycle theory,and the index system to evaluate the environmental impact of high-speed railway was established wi... Environmental impact evaluation system boundary of high-speed railway was defined based on the total life cycle theory,and the index system to evaluate the environmental impact of high-speed railway was established with the fuzzy analytic hierarchy method,and the matter-element evaluation model was established on the basis of the extension theory.By calculating its comprehensive interrelatedness,the evaluation rank of environment impacts of high-speed railway was determined.The numerical example shows that the model has vast prospect,which can not only expand the application areas of extension theory,but also change the traditional evaluation methods and provide new ideas and means for environmental impact evaluation of high-speed railway. 展开更多
关键词 high-speed railway life cycle environmental impact EVALUATION MATTER-ELEMENT
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