Results 61 to 70 of about 13,463 (225)
Rare Metals, Volume 45, Issue 3, March 2026.ABSTRACT Platinum (Pt)‐based catalysts are crucial for the commercialization of hydrogen/metal air batteries, but they suffer from Pt scarcity, high cost, and nanoparticle dissolution/agglomeration, mainly leading to performance degradation. We address this by synthesizing a PtFe alloy catalyst (PtFe–PA–NC) via a phytic acid (PA) assisted pyrolysis ...
Chenyang Shu +9 more
wiley +1 more source
MONTE CARLO SIMULATION ON BULK RING-OPENING COPOLYMERIZATION OF OCTAMETHYLCYCLOTETRASILOXANE WITH N-β-AMINOETHYL-γ-AMINOPROPYLMETHYLDIMETHYOXYSILANE [PDF]
, 2004 应用MonteCarlo方法模拟八甲基环四硅氧烷与N β 氨乙基 γ 氨丙基甲基二甲氧基硅烷 (D4/APAEDMS)的本体开环共聚动力学 .在兼顾模拟精度与计算经济性基础上 ,模拟过程采用自由体积理论简化处理扩散效应并与本征反应动力学耦合 .本征动力学常数通过模拟主要共聚基元反应得到 ,基于优化的动力学常数通过模拟从分子水平揭示 :(1 )D4/APAEDMS本体开环共聚存在总活性基团的“稳态”行为 ;(2 )D4/APAEDMS本体开环共聚反应过程的重均分子量与数均分子量以及分子量分布系数存在“突变”
罗正鸿 +3 more
core
Rare Metals, Volume 45, Issue 3, March 2026.ABSTRACT Aqueous vanadium dioxide (VO2)‐based smart thermal insulation coatings represent a viable strategy to decrease building energy consumption and advance sustainable development goals. However, the inherent instability and limited compatibility with polymer matrices of VO2 hinder its widespread application.
Xiuxian Zhao +9 more
wiley +1 more source
Zhejiang Daxue xuebao. Lixue ban, 2007 以过硫酸铵和季戊四醇为氧化还原引发体系引发丙烯酰胺(AM)与甲基丙烯酰氧乙基三甲基氯化铵(DMC)自由基共聚合，采用FTIR和1H-NMR进行结构表征.研究了引发剂用量、单体配比及浓度对星形阳离子型聚丙烯酰胺共聚物特性粘数及阳离子度的影响，并用于处理高岭土废水，其絮凝效果明显优于相应的均聚物及线形共聚物.
ZHENGBao-qing(郑宝庆) +1 more
doaj +1 more source
Biogeochemical implications of mangrove plant polyphenols and their antioxidant activities [PDF]
, 2012 植物多酚由于其特殊多样的生物化学活性，逐渐成为化学生态学、生物地球化学、药理学和食品化学等交叉学科的研究热点。红树植物多酚具有多样性含量分布和结构组成是红树林与环境长期协同进化的结果。有关红树植物多酚生物地球化学及结构-活性的研究在国际上处于起步阶段。本研究联合多种分析技术，包括13C-NMR、MALDI-TOF质谱、正相/反相HPLC-ESI-MS，凝胶色谱柱法，化学降解法，比色法等，研究了植物多酚在红树林湿地生态系统的生物地球化学循环及结构与抗氧化活性关系，为揭示红树植物的营养保存机制奠定理论基础 ...
周海超
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Factors That Influenced Coping With COVID‐19 During the Pandemic in Botswana
World Medical &Health Policy, Volume 18, Issue 1, March 2026.ABSTRACT This paper forms part of the broader Global South study, Personal and Family Coping with COVID‐19 in the Global South, which examines psychosocial and behavioral responses to the COVID‐19 pandemic. In Sub‐Saharan Africa, the pandemic posed significant psychological, social, and economic challenges, with important implications for preparedness ...
Magen Mhaka‐Mutepfa +3 more
wiley +1 more source
Gaoya dianqi, 2017 为了探究温度和湿度对掺杂纳米氧化铝的聚酰亚胺（PI）薄膜耐电晕性能的影响,文中通过原位聚合法制备了氧化铝粒径为20 nm的聚酰亚胺/氧化铝（PI/Al2O3）复合薄膜,在高频方波脉冲下进行纯膜和纳米膜的耐电晕实验,运用扫描电镜对电晕老化前后的薄膜形貌进行分析。实验结果表明:同一电压下,纳米膜耐电晕性能优于纯膜,纳米粒子可改变电荷传输通道,并浮于聚合物表层阻挡进一步侵蚀。随着温度升高,聚合物降解产生的气体分布在基体中,易造成电场畸变而加剧侵蚀,导致薄膜寿命缩短;且纳米膜热导率高于纯膜 ...
钟鑫, 吴广宁
doaj
The MALDI-TOF MS of Vegetable Tannins [PDF]
, 2007 在对植物单宁重要的生态功能，显著的生理学、药理学活性，对人体、家畜健康的重大影响、巨大应用价值和新用途的开发等领域的研究中，都需要对植物单宁的化学结构进行快速、简便且准确地分析。基质辅助激光解吸附离子化飞行时间（MALDI-TOF）质谱对分析多分散的植物单宁聚合物是一种理想的工具。本文着重对1）样品在MALDI过程中的裂解对准确分析单宁结构的影响，2）样品前处理过程对准确分析植物单宁结构的影响，3）MALDI-TOF质谱与13C-NMR联合应用于未知缩合单宁的结构分析等作了深入的探讨。通过本部分的研究 ...
向平
core
Functional Ecology, Volume 40, Issue 3, Page 636-654, March 2026.Read the free Plain Language Summary for this article on the Journal blog. Abstract The nested subset pattern (nestedness) has been widely used to explain species distributions in island and fragmented systems. Mountain sky islands serve as critical natural laboratories for understanding the evolutionary consequences of geographic isolation and climate
Caiwen Zhang +5 more
wiley +1 more source
Latin American Policy, Volume 17, Issue 1, March 2026.ABSTRACT Tourism and International Relations, as interdisciplinary fields, encompass diverse knowledge, making them complex subjects. This article explores how official international relations bodies at subnational levels influence tourism using paradiplomacy and city diplomacy concepts.
Juliane Santos Lumertz +3 more
wiley +1 more source