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Kongjian kexue xuebao, 2023 X射线掩星是一种常见的天文现象，基于X射线掩星探测的大气密度反演是一种涉及学科交叉的新方法，其通过处理高能X射线天体辐射源的掩星观测数据实现大气密度的反演，基本原理为X射线在大气中传播时，X射线光子被大气中的原子（包括分子中的原子）吸收和散射，从而导致X射线强度发生衰减，根据衰减后X射线信号的强度反演对应的密度廓线。本文根据X射线掩星探测的应用需求，论证了基于X射线掩星实现大气密度反演的新方法，重点介绍了光变曲线拟合和能谱拟合两种地球中高层大气密度反演算法 ...
余 道淳 +3 more
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Kongjian kexue xuebao, 2023 行星岩石成分原位测量是行星探测的基本需求，X射线荧光分析是开展元素成分测量的重要技术手段。针对深空探测X射线荧光分析仪的需要，设计并研制了一款微型微焦斑X射线闭管，尺寸为Φ15 mm × 22 mm，焦斑尺寸230 μm，工作时阳极接地，阴极接浮地负高压，最大电压为–50 kV。在微型X射线闭管研制过程中，开展了螺旋型钨丝、直线型钨丝、直线型铼钨丝等常用热阴极的电子发射差异性研究，测量了各型热阴极的电子发射效率。结果显示，在200 V阳极电压下，低铼含量直线型铼钨丝电子发射效率最大为27.87 μA·W–
李 帆 +5 more
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Kongjian kexue xuebao, 2023 核爆炸的大部分能量是以X射线形式释放的，研究X射线辐射特性对于天基核爆事件监测，当量反演都具有一定参考价值。根据核爆炸X射线能谱特性，构建了黑体辐射模型；根据NRLMSIS大气模型成分数据和高度密度数据，构建大气分层数值模型，并结合NIST数据库，构建分层大气质量吸收系数模型，提高了大气模型与大气质量吸收系数模型准确度。使用数值模拟程序对X射线在大气中的传输特性进行研究，模拟在临近空间高度核爆炸产生的X射线经过大气吸收后的能谱特性以及不同海拔高度点位的能注量。结果表明，在检测点高度恒定的情况下 ...
吕 致辉 +4 more
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Kongjian kexue xuebao, 2023 先进天基太阳天文台卫星（ASO-S）是中国首颗综合性太阳观测任务，太阳硬X射线成像仪（HXI）是ASO-S卫星三大载荷之一，主要负责太阳耀斑观测。HXI采用阵列空间调制间接成像方法，包含91个子准直器单元。发射前，在地面对HXI进行调制参数定标非常必要，但由于没有平行的X射线源而十分困难。本文根据HXI的基本原理与设计方案，提出了基于地面调制功能定标的设备与HXI调制定标的需求。根据所述需求，介绍了研制的X射线束流调制定标装置；利用该装置对HXI飞行件上所有子准直器完成地面调制功能定标 ...
陈 灯意 +3 more
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Rare Metals, Volume 45, Issue 6, June 2026.ABSTRACT NiTi shape memory alloys (SMAs) show excellent performance in vibration damping and corrosion resistance. However, due to low hardness and lack of self‐lubrication, they suffer severe friction and wear during service. Although various strategies including doping and heterostructure design have been proposed, the effects are unsatisfactory.
Huwen Ma +13 more
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Rare Metals, Volume 45, Issue 6, June 2026.ABSTRACT The intricate corrosion environment necessitates the polymeric coating's adaptability to the surroundings. In this work, the integration of rare‐earth Ce(III) ions and ethylene diamine tetramethylene phosphonic acid (EDTMP) in a layered double hydroxide (LDH) material is developed to enhance the corrosion protection and anti‐wear properties of
Yangu Liu +9 more
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Rare Metals, Volume 45, Issue 5, May 2026.ABSTRACT Managing diabetic wounds requires simultaneously addressing their infectious, oxidative, and regenerative impairments. To address this, this study integrates a piezoelectric BiOCl@CuSe heterojunction (PFM‐verified) into an injectable F127/HA hydrogel, creating an ultrasound‐responsive smart dressing.
Jiayan Guo +5 more
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Rare Metals, Volume 45, Issue 5, May 2026.ABSTRACT Multicomponent transition metal oxides (TMOs) incorporating rare‐earth (RE) elements have emerged as promising materials for the oxygen evolution reaction (OER). However, knowledge of how to regulate the structure of TMO‐based nanomaterials through RE incorporation to enhance catalytic performance remains limited.
Bolin Zhao +6 more
wiley +1 more source
Rare Metals, Volume 45, Issue 5, May 2026.ABSTRACT Additive manufacturing, commonly referred to as three‐dimensional (3D) printing, provides the geometric freedom and multi‐material integration needed to build soft medical robots for minimally invasive interventions, prosthetics, and rehabilitation.
Yao Wang +5 more
wiley +1 more source
四川大学学报. 自然科学版, 2011 X射线透射复合材料时发生了康普顿散射现象、二次射线的辐射和多次射线辐射.基于Beer定律,探讨了X射线在复合材料中的二次射线与一次射线的关系.由射线辐射强度方程求得X射线在复合材料中多次射线强度与透射厚度的定量关系,结果表明射线透射强度与能量无关.由散射光子在复合材料中倾斜同一角度时射线的强度微分方程,导出了X射线在复合材料中多次射线辐射强度公式和总强度.
彭光含
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