Results 31 to 40 of about 104,408 (159)
Shuitu Baochi Xuebao, 2022 冻融循环作用下的土壤结构变化被认为是融雪期黑土坡面土壤侵蚀加剧的主要原因之一, 土壤团聚体稳定性与团聚体微结构是影响土壤可蚀性的关键因子。基于控制条件土壤冻融模拟试验, 采用湿筛法、扫描电子显微技术(SEM)和Image-Pro Plus(IPP)图像分析处理相结合的方法, 分析了冻融循环过程中黑土团聚体微结构的动态变化特征, 阐明了土壤团聚体水稳定性与团聚体微结构特征的内在联系。结果表明: (1)冻融循环对黑土团聚体水稳定性整体呈破坏作用。该作用在微观层面上表现为冻融循环驱动土壤孔隙趋于长条状发育 ...
王文刚 +4 more
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Functional Ecology, Volume 40, Issue 8, Page 2590-2601, August 2026.Read the free Plain Language Summary for this article on the Journal blog. Abstract Permafrost thaw is reshaping nutrient dynamics in boreal forests, but its impacts on tree nutrient limitation and functional strategies remain poorly understood. Clarifying these responses is crucial for predicting the response of boreal forests to climate change.
Qiyue Fu +9 more
wiley +1 more source
Shuitu Baochi Xuebao, 2019 为理解煤对土壤结构的影响，以土壤煤累积现象普遍的焦作矿粮复合区为研究区，选取3种不同程度的煤累积土壤（低累积、中累积和高累积）为研究对象，不含煤的土壤为对照，通过测定0-40 cm土层深度范围的水稳性团聚体组成，并采用分形维数（D）、平均重量直径（MWD）、几何平均直径（GMD）和大团聚体破坏率（PAD）作为团粒结构的评价指标，探讨煤累积对土壤团聚体组成与稳定性的影响。结果表明：煤在土壤中累积可以促进水稳性微团聚体向大团聚体转化，降低团聚体的分形维数，提高团聚体稳定性。深层（20-40 cm ...
聂小军 +5 more
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Policy Studies Journal, Volume 54, Issue 3, August 2026.Abstract Studies of lobbying typically look at the extent to which interest groups realize political goals on issues they actively lobby for. Little is known, however, about the extent to which interest groups attain their political goals without making an active lobbying effort.
Marcel Hanegraaff +2 more
wiley +1 more source
Gaoya dianqi, 2017 气体绝缘金属封闭输电线路（gas-insulated transmission line,GIL）绝缘子在直流电压长期作用下,会积聚表面电荷,引起绝缘子沿面闪络电压降低,导致闪络事故。因此研究绝缘子在长期直流耐受下的表面电荷积聚现象,对气—固界面在直流电压下的电荷积聚机理进行分析,建立更为完善的表面电荷积聚模型,具有重要的理论意义和工程价值。笔者基于3种已有的表面电荷积聚模型、分界面电荷弛豫方程和更为普适的稳态电荷密度方程,利用微元法对盆式绝缘子表面电荷分布进行了数值计算。结果表明 ...
杜乾栋 +6 more
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Microstructure Engineering Toward High Cost‐Effective Nd–Fe–B Sintered Magnets: A Review
Rare Metals, Volume 45, Issue 7, July 2026.ABSTRACT Nd–Fe–B sintered magnets, critical for enhancing electromechanical conversion efficiency and operational stability in wind turbines and electric vehicle drives, are prized for their outstanding coercivity, high remanence, and superior maximum energy product.
Dongmin Zhang +5 more
wiley +1 more source
Rare Metals, Volume 45, Issue 7, July 2026.ABSTRACT This study developed a metal–modified fluoroethylene vinyl ether (FEVE) organic coating on 6061 aluminum alloy, supported by a micro‐arc oxidation (MAO) pretreatment layer, to enhance corrosion resistance and antifouling performance in marine environments.
Chang Liu +5 more
wiley +1 more source
Rare Metals, Volume 45, Issue 7, July 2026.ABSTRACT Biodegradable zinc (Zn)‐based materials are considered promising candidates for orthopedic applications because of their favorable mechanical properties, controllable biodegradability, and good biosafety profiles. However, their clinical translation is limited by early‐stage corrosion‐induced cytotoxicity and inflammation, as well as ...
Jinlong Mao +9 more
wiley +1 more source
Microphase separation of mixtures of two diblock copolymers(两嵌段共聚物共混体系的相分离研究)
Zhejiang Daxue xuebao. Lixue ban, 2009 用耗散粒子动力学方法(DPD)研究了由两种不同成分组成的两嵌段共聚物组成的混合体系在纳米尺度下的自组装行为.两种嵌段共聚物的聚合度相同,在稳定状态下,纯嵌段共聚物1呈层状有序结构,纯嵌段共聚物2呈无序或六角柱状结构.DPD研究表明,在两者混合体系中,随着嵌段共聚物2体积分数的增加,嵌段共聚物1只出现了层状的有序相,而嵌段共聚物2则呈现出从球状相到柱状相再到层状有序相的有趣变化,随着嵌段共聚物2对称性的增强,其形成的有序相所占的体积分数区域越小.同时,通过混合体系单体密度分布曲线和末端距分布情况 ...
LUOJin(罗进), HELin-li(何林李)
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Rare Metals, Volume 45, Issue 7, July 2026.ABSTRACT Bone defect repair in elderly patients is frequently compromised by reduced osteogenic capacity and delayed healing. Chronic inflammation‐driven inflammaging is a critical contributor to this impairment, characterized by dysfunctional autophagy in senescent macrophages (S‐MΦs), excessive reactive oxygen species (ROS) accumulation, and ...
Ruiyue Hang +6 more
wiley +1 more source