Results 91 to 100 of about 1,133,740 (188)

Constructing Integrative Catalytic Pairs in Carbon Nanohorns for Enhanced Neutral H2O2 Electrosynthesis

open access: yesRare Metals, Volume 45, Issue 9, September 2026.
ABSTRACT Electrosynthesis of hydrogen peroxide (H2O2) via the two‐electron oxygen reduction reaction (2e−ORR) offers a sustainable and decentralized alternative to the anthraquinone process. However, conventional solo‐active‐site catalysts are intrinsically limited by scaling relationships, imposing a trade‐off between activity and selectivity.
Yiqi Ding   +12 more
wiley   +1 more source

香港地区雷击现象统计分析

open access: yesDianci bileiqi, 2016
雷电的统计分布特性是雷电科学研究的重要基础。利用香港2005年至2014年雷电闪监测资料,进行了雷电的时域分布和雷电流的统计分布特性分析。研究表明:十年雷电总数的逾半数集中分布于极少数日子,深入挖掘相关数据可以为电力系统防雷提供新的可能。香港地闪雷电流幅值频率分布特征随闪电极性有显著差异,负闪雷电流幅值及出现频次均高于正闪。利用IEEE雷电流幅值概率分布公式计算了雷电流幅值的概率密度分布曲线方程,能较准确地反映香港雷电活动规律。
黄礼忠   +4 more
doaj  

Enhanced Oxygen Reduction Reaction Performance of Fe‐N4 Single‐Atom Catalysts Through Fe3C Coupling

open access: yesRare Metals, Volume 45, Issue 9, September 2026.
ABSTRACT Understanding the electronic factors contributing to the high oxygen reduction reaction (ORR) activity of Fe‐N4 sites remains a significant challenge due to the localized Fe 3d orbitals and their sensitivity to the coordination environment.
Shichang Cai   +19 more
wiley   +1 more source

白蜡虫花翅跳小蜂空间分布型及种群动态的研究

open access: yes四川大学学报. 自然科学版, 1995
对白蜡虫危害极严重的寄生蜂——白蜡虫花翅跳小蜂幼虫的空间分布型及种群动态进行了研究,认为其分布为聚集分布,可以用负二项分布、Neyman分布和Poisson-二项式分布来拟合,用Iwao的平均拥挤度(m)与平均密度(X)的直线回归法做了拟合,得出m=0.27+1.21X,改进的Iwao模型为m=0.15+0.16X+1.57X ̄2,同时给出其属于负二项分布的理论抽样数及序贯抽样公式。用模糊聚类法将其动态分为4个状态集(亚系统).并以平均密度为指标给出其种群在寄生于雌蜡虫体内的增长曲线.
朱玮, 吴次彬
doaj  

Engineering Stress‐Decoupled SnP2O7@Carbon Core Shell via Spatial Confinement for Cycling‐Stable Sodium Storage

open access: yesRare Metals, Volume 45, Issue 9, September 2026.
ABSTRACT Tin‐based composite oxides typically undergo severe volume variations and exhibit poor intrinsic conductivities despite their high theoretical capacity as promising anode candidates for sodium‐ion batteries. This results in rapid structural degradation and capacity fading upon cycling.
Yongmei Sun   +5 more
wiley   +1 more source

长串高压硅堆的电压分布与不等值均压分析

open access: yesGaoya dianqi, 2009
内部均压是高压硅堆研制的关键技术,而硅堆电压分布不均的现象在端部最为突出。以硅堆分布参数等效电路为基础,先采用解析方法分析硅堆内部电压分布规律和影响因素,针对硅堆端部电压分布尤其不均匀的特点,建立EMTP仿真模型,分析端部强制均压元件参数对硅堆电压分布不均匀系数的影响。提出采用非等值均压参数配置方法改善端部电压分布,并通过实验验证了这种非等值均压参数配置方法对改善高压硅堆电压分布不均匀度的效果。研究表明,这种端部均压方法能有效降低硅堆端部的分压,从而提高硅堆整体的反向耐压。
张磊   +4 more
doaj  

影响生物土壤结皮分布的环境因子

open access: yes, 2010
生物土壤结皮广泛分布于干旱荒漠地区,在干旱和荒漠生态系统中,有重要的生态功能。然而,并不是所有的干旱荒漠区都有生物土壤结皮的分布。在全球和区域尺度上,生物土壤结皮的分布与年降水、凝结水量和土壤含水量呈正相关趋势;温度对生物土壤结皮分布的影响因组成生物土壤结皮的物种而异。小尺度范围内,生物土壤结皮的分布受土壤类型、质地和养分的限制;维管植物对生物土壤结皮分布的影响,暂没有一致的结论。适度干扰对生物土壤结皮分布和生态功能无明显影响,但高强度干扰导致生物土壤结皮结构、功能和分布的退化与减少 ...
张元明, 程军回
core  

Surface Reconstruction of Ce‐Ion‐Doped Fe‐MOF for Efficient Water Oxidation

open access: yesRare Metals, Volume 45, Issue 9, September 2026.
ABSTRACT Surface reconstruction plays an important role in catalysts for the efficient oxygen evolution reaction (OER). In this work, we report the designed synthesis of the Ce‐ion‐doped Fe‐MOF (CFM) directly grown on nickel foam via a facile solvothermal route.
Fangfang Zhang   +8 more
wiley   +1 more source

尼龙网方格沙障的风沙流颗粒分布特征

open access: yesShuitu Baochi Xuebao, 2016
为了探讨塔克拉玛干沙漠腹地风沙流结构特征及尼龙网方格沙障对风沙流颗粒的分异作用,于2015年4月—2015年6月,选取裸沙地和沙障2种下垫面,利用集沙仪对地表风沙流进行观测,分析了尼龙网沙障对风沙流结构和沙粒粒径分布的分异过程。结果表明:(1)风沙流结构在裸沙地符合指数分布(y=321.025e-10.16x,R2=0.94),在沙障前部和中部分别表现出“象鼻”效应特征和近似于倒置的“象鼻”;沙障的设置,明显减少了近地面(0~42 cm)的输沙量。(2)在裸沙地 ...
黎小娟, 李, 丁新原
doaj  

Electrically Switchable Altermagnetism in Monolayer MoCl3

open access: yesRare Metals, Volume 45, Issue 9, September 2026.
ABSTRACT Altermagnets intertwine spin‐split bands with vanishing net magnetization, offering great potential for high‐density, stray‐field‐free spintronic devices. However, their development is hindered by both material scarcity and difficulties in external control due to their intrinsic symmetry protection.
Zhengming Zhang, Zhenyu Fan, Dunhui Wang
wiley   +1 more source

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