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面向城市群的黄河流域生态脆弱性研究

环境科学研究 2025年第1期38卷 125-138页

作者：付刚李俊生齐月李庆王仁德柳天凤河北省科学院地理科学研究所河北省地理信息开发应用技术创新中心河北石家庄050011 中国地质调查局自然资源综合调查指挥中心北京100055 中国环境科学研究院生态文明理论研究中心北京100012

黄河流域是我国重要的生态屏障,其生态保护和高质量发展是重大国家战略,需要充分发挥城市群的引领作用。然而黄河流域上下游自然生态禀赋的差异和发展不平衡,以及各城市群之间协同合作不足,制约流域高质量发展。本文基于敏感-弹性-压力(... 详细信息

黄河流域是我国重要的生态屏障,其生态保护和高质量发展是重大国家战略,需要充分发挥城市群的引领作用。然而黄河流域上下游自然生态禀赋的差异和发展不平衡,以及各城市群之间协同合作不足,制约流域高质量发展。本文基于敏感-弹性-压力(SRP)模型和空间主成分法(SPCA)法构建黄河流域城市群生态脆弱性评价体系,对2020年山东半岛城市群、中原城市群、关中平原城市群、黄河“几”字弯都市圈和兰州-西宁城市群的生态脆弱性进行定量评估;同时基于层次聚类方法,对全域613个县域进行生态脆弱性区划,并探究人为活动对生态脆弱性的影响。结果表明:①2020年黄河流域城市群的生态脆弱性程度较高,平均值达到0.53,生态弹性是生态脆弱性的首要因子,权重为0.55。②在空间上,黄河流域城市群以中度脆弱区为主,面积占比为64.08%。③人为活动对生态脆弱性具有广泛影响,全域76.02%的县域表现出人为活动与生态脆弱性的显著相关性(P<0.05)。④研究确定了8种生态脆弱型,从空间分布来看,中东部农业敏感型地区的面积占比最大,为30.40%,而中心城区脆弱型和矿业脆弱型地区的面积占比最小,分别为0.37%和0.25%。研究显示,黄河流域各城市群的生态脆弱度不同,生态脆弱度最高的是山东半岛城市群和黄河“几”字弯都市圈,建议采取针对性的空间布局优化和生态修复措施,推进城市群的可持续发展。

关键词：城市群都市圈黄河流域生态敏感性层次聚类人为干扰

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Formation of hierarchical Si3N4 foams by protein-based gelcasting and chemical vapor infiltration

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Journal of Advanced Ceramics 2021年第1期10卷 187-193页

作者： junsheng li Qiuping YU Duan li liang ZENG Shitao GAO Science and Technology on Advanced Ceramic Fibers and Composites Laboratory College of Aerospace Science and EngineeringNational University of Defense TechnologyChangsha 410073China

Silicon nitride foams with a hierarchical porous structure was formed by the combination of protein-based gelcasting,chemical vapor infiltration,and in-situ growth of silicon nitride *** porosity of the foams can be controlled at 76.3-83.8 vol%with an open porosity of 70.2—82.8 vol%.The pore size distribution was presented in three levels:licon nitride nanowires(SNNWs)),10—50μm(cell windows),and>100μm(cells).The resulted compressive strength of the porous bodies at room temperature can achieve up to 18.0±1.0 MPa(porosity=76.3 vol%)while the corresponding retention rate at 800℃was 58.3%.Gas permeability value was measured to be 5.16(cm^(3)·cm)/(cm^(2)·s·kPa).The good strength,high permeability together with the pore structure in multiple scales enabled the foam materials for microparticle infiltration applications.

关键词： ceramics sintering porosity mechanical properties permeability

Formation of macroporous gel morphology by phase separation in the silica sol-gel system containing nonionic surfactant

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Journal of University of Science and Technology Beijing 2005年第6期12卷 564-571页

作者： junsheng Wu Xiaogang li Wei Du Hua Chen Materials Science and Engineering School University of Science and Technology Beijing Beijing 100083 China

The phase separation and gel formation behavior in an alkoxy-derived silica sol-gel system containing C16EO15 has been investigated. Various gel morphologies similar to other sol-gel systems containing organic additives were obtained by changing the preparation conditions. Micrometer-range interconnected porous gels were obtained by freezing transitional structures of phase separation in the sol-gel process. The dependence of the resulting gel morphology on several important reaction parameters such as the starting composition, reaction temperature and acid catalyst concentration was studied in detail. The experimental results indicate that the gel morphology is mainly determined by the time relation between the onset of phase separation and gel formation.

关键词： silica sol-gel phase separation macroporous gel morphology nonionic surfactant

Biodiversity conservation in China:A review of recent studies and practices

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Environmental Science and Ecotechnology 2020年第2期2卷 30-39页

作者： Wei Wang Chunting Feng Fangzheng liu junsheng li State Key Laboratory of Environmental Criteria and Risk Assessment State Environmental Protection Key Laboratory of Regional Eco-process and Function AssessmentChinese Research Academy of Environmental SciencesBeijing100012China Biodiversity Research Center Chinese Research Academy of Environmental SciencesBeijing100012China

Biodiversity conservation plays an important role in the sustainable development of human *** had made significant progress in biodiversity conservation studies and *** paper reviews major achievements in China in the past decades,especially those since *** terms of the science behind biodiversity conservation,Chinese scholars have made significant contributions to priority research subjects,including mechanisms for maintaining biological communities and the relationship between biodiversity and ecosystem ***,biodiversity conservation and management systems specific to China have been basically *** Chinese Government and researchers have undertaken a number of investigations,scientific studies,and monitoring,and have established relevant *** efforts taken to protect and restore biodiversity and ecosystems,the concept of biodiversity has gradually become popular in *** review is an attempt to share with the world the learning from China’s progress towards becoming an ecological civilization and highlights that the efforts towards biodiversity conservation need to be organically integrated with sustainable development goals.

关键词： Ecological civilization Mainstreaming Mobile supervising system Sustainable development Protected areas

Spatial and temporal variation of water clarity in typical reservoirs in the Beijing-Tianjin-Hebei region observed by GF 1-WFV satellite data

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Journal of Oceanology and limnology 2024年第4期42卷 1048-1060页

作者： Chang CAO junsheng li Xiaodong JIA Shenglei WANG Bo WAN liaoning Earthquake Agency Shenyang 11000China Key Laboratory of Digital Earth Science Aerospace Information Research InstituteChinese Academy of SciencesBeijing 100094China International Research Center of Big Data for Sustainable Development Goals Beijing 100094China School of Electronic Electrical and Communication EngineeringUniversity of Chinese Academy of SciencesBeijing 100049China

Rapidly monitoring regional water quality and the changing trend is of great practical and scientific significance,especially for the Beijing-Tianjin-Hebei(BTH)region of China where water resources are relatively scarce and inland water bodies are generally *** remote sensing data of the GF 1 satellite launched in 2013 have characteristics of high spatial and temporal resolution,which can be used for the dynamic monitoring of the water environment in small lakes and ***,the water quality remote sensing monitoring model based on the GF 1 satellite data for lakes and reservoirs in BTH is still lacking because of the considerable differences in the optical characteristics of the lakes and *** this paper,the typical reservoirs in BTH-Guanting Reservoir,Yuqiao Reservoir,Panjiakou Reservoir,and Daheiting Reservoir are taken as the study *** the atmospheric correction of GF 1-WFV,the relative radiation normalized atmospheric correction was adopted after comparing it with other methods,such as 6 S and *** the water clarity retrieval,a water color hue angle based model was proposed and outperformed other available published models,with the R 2 of 0.74 and MRE of 31.7%.The clarity products of the four typical reservoirs in the BTH region in 2013-2019 were produced using the GF 1-WFV *** on the products,temporal and spatial changes in clarity were analyzed,and the main influencing factors for each water body were *** was found that the clarity of Guanting,Daheiting,and Panjiakou reservoirs showed an upward trend during this period,while that of Yuqiao Reservoir showed a downward *** the influencing factors,the water level of the water bodies can be an important factor related to the water clarity changes in this region.

关键词： GF 1 satellite atmospheric correction clarity Beijing-Tianjin-Hebei spatial and temporal change analysis

Three-dimensionally Ordered Macroporous Phosphotungstic Acid/SiO2 for Efficient Catalytic Oxidative Desulfurization

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Journal of Wuhan University of Technology(Materials Science) 2018年第4期33卷 849-854页

作者：杜岳 YANG Peng 雷家珩 ZHOU Shiyu li junsheng DU Xiaodi School of Materials Science and Engineering Wuhan University of TechnologyWuhan 430070China School of Chemistry Chemical Engineering and Life ScienceWuhan University of TechnologyWuhan 430070China

Three-dimensionally ordered（3DOM） macroporous phosphotungstic acid/SiO_2（HPW/SiO_2） materials were prepared by using colloidal crystal as templates and applied for oxidative desulfurization（ODS） of the model fuel oil. The obtained HPW/SiO_2 materials were characterized through scanning electron microscopy, powder X-ray diffraction, N_2 sorption, and Fourier transform infrared spectroscopy. The results indicated that 3 DOM HPW/SiO_2 possessed hierarchical pore architectures which contained ordered macropores and disordered mesopores, with the Keggin type HPW embedded in the framework of pore structure. The removal rate of dibenzothiophene（DBT） could reach 100% under the optimum conditions, moreover. The performance was only slightly decreased for the regenerated catalyst after 7 cycles.

关键词： three-dimensionally ordered macroporous SiO2 phosphotungstic acid oxidativedesulfurization

Interfacing soluble polysulfides with a SnO2 functionalized separator:An efficient approach for improving performance of li-S battery

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Interfacing soluble polysulfides with a SnO2 functionalized ...

Non-native species in marine protected areas: Global distribution patterns

中国化学会第三届中国能源材料化学研讨会

作者： Yinyu Xiang junsheng li School of Chemistry Chemical Engineering and Life SciencesWuhan University of Technology

＜正＞lithium-sulfur battery is a promising energy storage device due to its high theatrical capacity and environmental ***,the rapid performance degradation associated with the so-called "shuttle effect" during the charge-discharge process in a typical lithium-sulfur battery greatly limits its practical application.

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Environmental Science and Ecotechnology 2024年第6期22卷 198-205页

作者： Tianjian Song Yuxin Huang Lei Fang Yonghua li junsheng li Jiang Chang State Key Laboratory of Environmental Criteria and Risk Assessment Chinese Research Academy of Environmental SciencesBeijing100012China College of Water Sciences Beijing Normal UniversityBeijing100875China College of Ecology Lanzhou UniversityLanzhou730000China Command Center for Comprehensive Survey of Natural Resources China Geological Survey BureauBeijing100055China

Marine protected areas(MPAs)across various countries have contributed to safeguarding coastal and marine *** these efforts,marine non-native species(NNS)continue to threaten biodiversity and ecosystems,even within ***,there is a lack of comprehensive studies on the inventories,distribution patterns,and effect factors of NNS within *** we show a database containing over 15,000 occurrence records of 2714 marine NNS across 16,401 national or regional MPAs *** identify the primary mechanisms driving the occurrence of NNS,we utilize model selection with proxies representing colonization pressure,environmental variables,and MPA *** the environmental predictors analyzed,sea surface temperature emerged as the sole factor strongly associated with NNS *** sea surface temperatures are linked to increased NNS richness,aligning with global marine biodiversity ***,human activities help species overcome geographical barriers and migration ***,this influences the distribution patterns of marine introduced species and associated environmental *** global climate change continues to alter sea temperatures,it is crucial to protect marine regions that are increasingly vulnerable to intense human activities and biological invasions.

关键词： Distribution patterns Effect factors Marine protected areas Non-native species

LQR Control Scheme for Active Vehicle Suspension Systems Based on Modal Decomposition

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LQR Control Scheme for Active Vehicle Suspension Systems Bas...