Results 11 to 20 of about 205,791 (173)
Measurement of the A-Value of the Intersystem Transition in Al II at 2670 Å: Å Progress Report [PDF]
International Astronomical Union Colloquium, 1984 Ratios of intensities of spectral lines produced in the radiative decay of collisionally-excited levels of atomic ions are versatile indicators of electron density in astrophysical plasmas when one of the lines involves a metastable level (see the review by Feldman 1981 and references therein). Radiative transition probabilities (A-values) and electron
B. Carol Johnson, H.S. Kwong
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Optical spectrum of the post-AGB Star HD56126 in the wavelength interval 4010-8790 Å Å [PDF]
Astrophysical Bulletin, 2007 The optical spectrum of the post-AGB star HD56126 identified with the infrared source IRAS07134+1005 is studied in detail using high spectral resolution observations (R = 25000 and 60000) performed with the echelle spectrographs of the 6-m telescope. A total of about one and a half thousand absorptions of neutral atoms and ions, absorption bands of C2,
V. G. Klochkova +3 more
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, 2023 无序合金是一种新型金属材料，突破了传统的合金设计理念，表现出不同于传统合金的优异力学性能、冲击释能及剪切自锐特性，在高温、高压、高应变率等环境具有良好的应用前景。分析活性无序合金的冲击释能特性对其应用于军事领域有着重要的指导作用，能为弹药战斗部的设计提供参考。本文阐述了静动态力学实验中典型无序合金的反应释能现象；总结了撞击速度与活性无序合金释能超压、释能效率之间的关系；讨论了撞击速度、材料破碎程度及靶标特征等因素对活性无序合金释能机理的影响；归纳了制备工艺及元素类型对活性无序合金释能特性的调控效果 ...
谈梦婷 +5 more
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Gaoya dianqi, 2022 钻跨一体杆塔是一种能同时实现线路钻越和跨越的新型杆塔，该杆塔目前处于设计阶段但缺乏相应的防雷研究。为了研究不同的防反击措施对110 kV钻跨一体杆塔反击耐雷性能的影响，选取技术经济指标较优的防反击措施，文中采用电磁暂态程序ATP-EMTP仿真计算了110 kV钻跨一体杆塔在两种不同的防反击措施下的反击耐雷水平，比较分析了两种不同的防反击措施的技术经济性。针对钻跨一体杆塔导线布置方式与普通杆塔的不同，文中在计算过程中特别考虑了杆塔竖直导线上感应电压的电磁分量。研究结果表明 ...
盛金马 +6 more
doaj
Dianci bileiqi, 2023 为提高输电线路杆塔接地装置设计的科学性和针对性，在分析反击跳闸率和接地电阻的影响因素的基础上，提出了基于输电线路反击跳闸率控制目标和蒙特卡洛法择优筛选的杆塔接地电阻控制值的差异化设计方法。即充分考虑影响反击跳闸率的各因素，根据杆塔结构参数、绝缘子串参数、沿线土壤电阻率、地形、雷电参数等进行反击跳闸率计算和区段划分，对各区段反击跳闸率进行加权平均获得线路总体反击跳闸率，再将其与反击跳闸率控制目标进行比对，并通过蒙特卡洛法实现在多种区段划分和接地电阻控制值中的择优选择，作为杆塔接地电阻的优化设计控制值 ...
童雪芳 +5 more
doaj
The Tariff Trap: Why Funding Health Programs Through Tariffs Harms Both Health and Democracy
World Medical &Health Policy, Volume 18, Issue 2, June 2026.ABSTRACT In 2025, the Trump Administration imposed significant tariffs on imports to the US as part of aggressive trade negotiations with other countries. Tariffs have important impacts on health that include increases in the prices that consumers and businesses pay for goods and potential damage to global supply chains.
Holly Jarman, Miranda Yaver
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, 2021 为了优化单兵头面部防护装备结构,提升防护性能,首先开展了基于实爆场和激波管环境的裸头模抗爆炸冲击波对比测试。在此基础上,利用激波管对佩戴不同结构、不同防护等级的头盔-头模系统分别进行了正向及侧向爆炸冲击波防护性能测试,并对头盔-头模系统前部、前额部、顶部、后部、耳部以及眼部等重点区域的冲击波超压峰值和持续作用时间进行对比分析。实验结果表明,基于激波管的抗爆炸冲击波测试方法可替代外场实爆进行考核。受到冲击波正向作用时:两半盔头模顶部测点所测冲击波超压峰值约为喷管出口的1/6,是裸头模和一体盔头模的1/3 ...
张远平 +5 more
core
Policy, Waste, and Power: Textile Dumping in Chile's Atacama Desert
Latin American Policy, Volume 17, Issue 2, June 2026.ABSTRACT Globally, 87% of textile fibers end up incinerated or in landfills, with Chile bearing the brunt of this crisis. Every year, 39,000 tons of discarded clothing are illegally dumped in the Atacama Desert, turning it into a sacrifice zone for the Global North's waste economy.
Emma Minerva Brambilla
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“American Islam”: The Politics of Religious Authenticity in Iran
Digest of Middle East Studies, Volume 35, Issue 3, Summer 2026.ABSTRACT This article analyzes “American Islam” as a political category of religious authenticity in the Islamic Republic of Iran rather than as a fixed theological concept. Using a critical discourse‐analytic framework, it examines how Ayatollah Khomeini and Ayatollah Khamenei construct and operationalize the opposition between pure Muhammadan Islam ...
Fateh Saeidi
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Rare Metals, Volume 45, Issue 3, March 2026.ABSTRACT Single‐atom catalysis hinges on fundamental challenges in precisely controlling metal‐support interactions and rationally regulating metal–adsorbate relationships. Herein, we report a universal strategy for constructing highly efficient and well‐defined Cu(I) single‐atom catalysts based on a trifurcate AlL3 molecular support.
Donghui Zhang +9 more
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