Results 21 to 30 of about 9,196 (128)
Legislative Attention and Nonprofit Efficiency: A Link Across Sectoral Boundaries
ABSTRACT Government attention matters for nonprofit management and nonprofit‐government interactions. This study focuses on legislative attention, an important yet less‐studied aspect of government attention in public policy research, and examines its impact on nonprofit efficiency.
Yuhao Ba, Jessica Berrett, Jason Coupet
wiley +1 more source
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
doaj
Microphase separation of mixtures of two diblock copolymers(两嵌段共聚物共混体系的相分离研究)
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)
doaj +1 more source
ABSTRACT Urban expansion significantly impacts flood risk, particularly in rapidly growing areas where impervious surfaces exacerbate surface runoff. This study examines spatial patterns of urban growth and their effects on flood exposure in Mecklenburg County, North Carolina, from 2011 to 2021.
Pegah Madadi, Azad Sadeghi
wiley +1 more source
Contribution of microcosm experiments to conservation science
Abstract Microcosms, or miniature experimental systems, have been used to develop models and theories in ecology. However, their contribution to conservation science is unclear. We explored the application, design, and impact of microcosms in conservation science from 469 systematically identified articles published from 1986 to 2023.
Eleanor R. Stern +3 more
wiley +1 more source
Conservation grounded in traditional ecological knowledge, culture and hunting
Abstract For millennia, traditional hunting practices have provided a means of subsistence for numerous indigenous peoples worldwide. Not only do managed traditional hunting practices perpetuate Traditional Ecological Knowledge (TEK), but they also promote the sustainable utilization of natural resources.
Wu Fei +8 more
wiley +1 more source
环氧树脂在直流电场下易于积聚电荷造成局部电场畸变,进而诱发沿面闪络。文中建立了考虑离子产生、复合、迁移和扩散过程的电荷积聚模型,并在模型中计及了电导率的温度特性。研究了不同温度下气固界面电势、电场、电荷的分布及功率损耗变化,分析了温度对电荷行为和电场畸变率的影响。结果表明:表面电荷密度随温度升高而增大,三结合点处电荷密度最大;温度对切向电场的影响更大,随温度升高,电荷积聚的主要方式由表面传导向体传导转变;适当升温可以提高表面电荷积聚和消散速率,但高温会使表面电荷密度和泄漏电流增大,进而加剧畸变和损耗 ...
谢子豪 +5 more
doaj
ABSTRACT Two‐dimensional MXene‐based materials have recently attracted attention in supercapacitors and lithium ion batteries due to their excellent electrochemical performance. However, the capacity and agglomerate limits the development of MXene‐based materials.
Han Zhang +4 more
wiley +1 more source
为探究高寒湿地地下水咸化对土壤团聚体稳定性和有机碳库的影响, 以巴音布鲁克高寒湿地季节性地表积水区和常年干燥区土壤为研究对象, 设对照、微咸水、咸水和盐水4个矿化度, 地下水NaCl含量分别为0, 2, 6, 23 g/L, 使用湿筛的方法将土壤团聚体分成不同的粒径。结果表明: 地下水矿化度升高对0—10 cm土壤团聚体分布影响不大, 对10—30 cm土壤团聚体有显著影响。在10—30 cm土层中, >2 mm土壤团聚体质量百分比随着矿化度升高先降低再升高, 在2 g/L处理下降至最低1%~14 ...
愚广灵 +5 more
doaj
ABSTRACT Although magnetic carbon materials possess significant potential in the field of electromagnetic wave absorption (EWA) due to the synergistic effect of multiple attenuation mechanisms, the currently reported magnetic carbon EWA materials face some challenges, such as high cost, low yield, and easy agglomeration of the magnetic component ...
Bo Jiang +9 more
wiley +1 more source

