Results 61 to 70 of about 12,025 (172)

Acid‐Etched Co‐Vacancy‐Tunable CoFeP/N,P‐Codoped Carbon Nanocages for Highly Efficient Alkaline Water Electrolysis

open access: yesRare Metals, EarlyView.
ABSTRACT Efficient and durable bifunctional electrocatalysts are vital for scalable water electrolysis. Here, we realize cobalt‐vacancy (Covac) engineering in CoFeP supported on N,P‐codoped carbon nanocages (Co1‐vacFeP/NPC) through a simple route comprising a CoFe Prussian blue analog precursor, phosphidation–pyrolysis, tannic‐acid etching, and a ...
Yuan‐Liang Yuan   +6 more
wiley   +1 more source

植物根系吸水对非饱和土边坡稳定性影响的分析

open access: yesShuitu Baochi Xuebao, 2022
为了量化植物根系吸水对非饱和土边坡稳定性的影响及为植被护坡的植物种类选择提供参考,采用COMSOL Multiphysics建立二维边坡,模拟不同根系形态、根长及降雨条件下的根系吸水引起的非饱和土边坡孔隙水压力的分布变化,并采用极限平衡理论对边坡稳定系数进行定量计算。结果表明:指数形根系吸水产生的吸力最大,比裸坡增大4.2倍,抛物线形根系吸水产生的吸力最小,但仍比裸坡增大2.7倍;根系越长吸水影响深度越大;根系越短,产生的吸力越大,且吸力在边坡表面的变化越显著;短期降雨后,含根系边坡吸力比裸坡高12 ...
钟彩尹   +4 more
doaj  

Insist on the Strategy of Forestry Sustainable Developmnet [PDF]

open access: yes, 1999
该文分析比较了前人在杉木林和火力楠林两种林分的林冠、枯枝落叶层、土壤结构与肥力、土壤微生物等因素保持水土方面的研究成果,从战略上提出了长泰县林业可持续发展对策。The paper analyzes and makes comparison among the research achievements in water and soil conservation by leaves, defoliation layer,soil structure and fertility, soil ...
史大林, 洪海征, 黄璜
core  

Performance Research and Infrared Spectroscopy Analysis of Asphalt Concrete with Iron Tailings [PDF]

open access: yes
This is an article in the field of ceramics and composites. The performance of asphalt mixtures with different iron tailings content was analyzed. The rutting resistance, water stability and crack resistance of the asphalt mixture were analyzed.
Heping CHENG, Li WANG, Youtao WANG
core   +1 more source

Bimetallic Mo/Fe‐Doped CoP2 Nanoleaf Array as a Bifunctional Electrocatalyst for Overall Water Splitting

open access: yesRare Metals, EarlyView.
ABSTRACT The development of efficient and stable bifunctional catalysts remains a key challenge for green hydrogen production via electrochemical water splitting. In this study, a bimetallic Mo/Fe‐doped CoP2 nanoleaf array anchored on carbon cloth (Mo, Fe‐CoP2@CC) was synthesized from zeolitic imidazolate framework‐L (ZIF‐L) via an ion‐exchange and low‐
Xiangqun Zeng   +6 more
wiley   +1 more source

The Influence Analysis of the Braces on Retaining Wall during the Excavation of Metro Pits [PDF]

open access: yes, 2013
城市地铁的深基坑开挖一般都位于交通、人流和建筑物密集的中心城区,施工场地相对狭窄,而且需要考虑到对周边建筑物、道路等工程设施的保护,这种复杂环境下的施工对稳定和变形控制相当严格。本文以厦门地铁一号线工程为依托,选取位于繁华市区的吕厝站基坑的典型断面,用岩土有限元软件PlAXIS模拟基坑分步开挖过程,研究所布置多道支撑的轴力、层数、间距和位置变化时对围护墙的水平位移和内力的影响,本项研究可供设计方案优化时参考。Deep excavations of urban subway system are ...
刘洋, 林树枝
core  

Broad‐Spectral Response Lead Halide Perovskite Solar Cells Through Integration of Multifunctional Organic Bulk‐Heterojunction and Quantum‐Cutting Downconversion Materials

open access: yesRare Metals, EarlyView.
ABSTRACT Expanding near‐infrared (NIR) spectral response and utilizing ultraviolet (UV) photons are effective strategies for enhancing the power conversion efficiency (PCE) of lead halide perovskite solar cells (PSCs). However, the range of NIR spectral response extension and the utilization of UV light for devices are not enough, and the loss of ...
Li He   +9 more
wiley   +1 more source

不同环境因素对复合绝缘子憎水性影响的研究

open access: yesGaoya dianqi, 2018
为研究复合绝缘子在不同环境中憎水性的变化规律,搭建了复合绝缘子试验平台,模拟电晕放电,盐密、灰密,磨损等环境因素,并采用静态接触角法和喷水分级法,测试了憎水性在不同环境中的丧失和恢复特性。试验结果表明:电晕放电会导致复合绝缘子憎水性呈现出先线性后缓慢的下降趋势,在电晕放电停止后,憎水性呈现出先线性上升后趋于稳定的恢复特性;而电晕老化的加剧会导致部分试品无法恢复到初始的憎水性能;憎水性在不同盐密、灰密下呈现出先近似指数上升后趋于稳定的迁移特性;高灰密时憎水性迁移速度更快并且稳定后达到更高的静态接触角值 ...
许竟   +4 more
doaj  

Bottom‐Up Strategy Toward 3D Porous MXene/MoS2 Nanosheets/Graphene Nanoarchitectures as Highly‐Efficient Hydrogen Evolution Electrocatalysts

open access: yesRare Metals, EarlyView.
ABSTRACT As a core component in the electrochemical water splitting system, the cathode catalyst is capable of boosting the kinetics of the hydrogen evolution reaction (HER), while the scarcity and expenditure of current noble metal‐based electrocatalysts seriously restrict the large‐scale commercial development of hydrogen manufacturing devices. Here,
Haiyan He   +8 more
wiley   +1 more source

黑龙滩水库消落带植被恢复模式对土壤水稳性团聚体组成及其稳定性的影响

open access: yesShuitu Baochi Xuebao
[目的] 为阐明水库消落带不同植被恢复模式对土壤水稳性团聚体组成及其稳定性的影响。[方法] 以川中丘陵区黑龙滩水库消落带人工恢复与自然恢复植被下的土壤为研究对象,利用湿筛法测定分析土壤水稳性团聚体组成特征及其稳定性指标。[结果] 消落带土壤>0.25 mm水稳性大团聚体含量与未淹水对照相比降低4.21%,其中,自然恢复植被下土壤水稳性大团聚体含量较对照下降12.27%,人工恢复植被下大团聚体含量较对照增加3.84%;不同植被恢复模式下土壤水稳性团聚体组成差异显著(p<0.05 ...
白芹菲   +5 more
doaj  

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