Results 41 to 50 of about 1,713,701 (148)
Rare Metals, Volume 45, Issue 3, March 2026.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
Dianci bileiqi, 2019 接地网是电力系统重要的防雷、防静电及过电压防护设施,在接地网设计或施工前进行接地模拟试验是预测接地网接地参数、衡量接地体接地特性的常用方法。石墨复合接地材料、多层电镀接地体、扁状等一系列非圆柱形接地体在采用相似理论进行接地模拟试验时,经常面临多个相似项不能按照相似准则进行缩比的问题。首先采用量纲分析法,提出了考虑接地体的三维尺寸、接地体材料参数等相似项的接地模拟试验完全相似模型。随后,提出接地模拟试验中畸变相似项、畸变系数、单畸变相似模型以及多畸变相似项等概念,给出接地模拟试验畸变相似模型的数学表征法 ...
胡元潮 +5 more
doaj
World Medical &Health Policy, Volume 18, Issue 1, March 2026.ABSTRACT Population aging is a problem that countries around the globe are facing; it comes with complex healthcare needs. Different countries take different approaches to solving these issues. In the United States, proposed legislation related to hospice and palliative care emerged from a history of hospice fraud and specialty physician shortages.
Edith‐Marie Green
wiley +1 more source
, 2005 提出了复杂流动相似准则的数值优化方法,即通过敏感性分析,从众多无量纲参数中筛选控制流动的主要相似参数.给出了敏感因子的定义,讨论了敏感因子与无量纲量间的依赖关系.并利用该方法对油藏渗流的相似准则进行研究,与理论分析进行对比,得到完全一致的结论.进一步对模型与原型压力分布的误差进行了合理的解释.最后分析了流动参数对敏感因子的影响 ...
李家春, 周济福
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分子中alphaCH键对硝基芳香族炸药材料的能量迁移率的影响
四川大学学报. 自然科学版, 2014 利用密度泛函理论,在B3LYP∥6-31G(d)计算水平上对含alphaCH键的三硝基苯类炸药分子的电子结构和红外振动进行了理论计算,对相关的红外振动模式进行了理论归属.并计算了材料分子在alphaCH键邻位和对位处与硝基相关的门模式的能量迁移率,发现材料分子在alphaCH键邻位处与硝基相关的门模式的能量迁移率数值低于其在对位的数值.将计算结果与撞击感度实验值进行对比,发现当alphaCH键处取代基的结构相似时,分子在alphaCH键邻位的能量迁移率与撞击感度有较好的线性相关关系 ...
董光兴 +3 more
doaj
He jishu面对跨学科科学文献的指数级增长与现有检索系统的局限性，本研究基于arXiv平台266万篇论文数据集，创新开发了融合向量语义检索与大型语言模型（Large Language Model，LLM）分析的智能系统。通过构建论文向量数据库实现语义相似性初筛，结合LLM上下文推理优化排序，有效解决了传统关键词搜索的语义鸿沟问题以及LLM的幻觉问题。在核物理领域的应用表明，该系统能精准定位跨学科解决方案，对比特定任务上的关键词检索和向量相似度检索，前10篇文献的查全率从10%跃升到60%，查准率从20%跃升到90%。
庞 龙刚
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Gaoya dianqi, 2021 模块化多电平换流器(modular multilevel converter,MMC)的可靠性关系到直流输电系统的安全稳定运行。文中首先基于MMC单个子模块可靠性模型的分析,利用拉丁超立方采样及Cholesky分解排序法产生计及子模块可靠性相关的场景;然后,在产生子模块相关性场景的基础上,利用极大似然估计理论得到3种Copula函数的相关系数,并利用最短欧式距离选取最优的Copula函数;其次,基于MMC子模块组合关系图及Copula理论,建立了计及子模块相关性的MMC可靠性分析模型。最后 ...
许启东 +3 more
doaj
Rare Metals, Volume 45, Issue 2, February 2026.ABSTRACT The similar physicochemical properties of alkali metal elements make the co‐enrichment and precise separation of Cs+ and Rb+ in complex brine systems highly challenging. Here, an all‐inorganic strategy is proposed, which achieves efficient enrichment and precise separation of Cs+ and Rb+ in high‐salt systems by constructing Sr2+/Ba2+‐based ...
Kang Li, Ruixin Ma, Shina Li
wiley +1 more source
四川大学学报. 自然科学版, 1962 §1.引言共轭相似空间是特殊的一类型Banach空间,它首先由日本数学家Nakano引出①。关于其上的非线性算子方程的理论Yamamuro曾在中讨论过,本文是在Yamamuro所得结果的基础上更进一小讨论有关这方面的理论并进而给出这些理论的某些应用。下面我们首先引出几个以后要用到的概念。设R是一Riesz空间,其满足如下的条件:对R内的任一列元素是指标集 ...
张石生
doaj
Contribution of microcosm experiments to conservation science
Conservation Biology, Volume 40, Issue 1, February 2026.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