Results 61 to 70 of about 27,614 (267)
ABSTRACT Transition metal‐based amorphous/crystalline (a/c) heterostructured catalysts have garnered significant attention due to their exceptional activity, stability, and cost‐effectiveness. However, the precise synergistic regulation of interfacial composition and phase states remains challenging.
Haoran Li +3 more
wiley +1 more source
First-principles calculations of perpendicular magnetic anisotropy in Fe1-xCox/MgO(001) [PDF]
近年来,垂直磁隧道结由于在磁记录、磁随机存储器、微波探测器以及磁敏传感器等方面的广阔应用前景引起人们广泛的关注。其中由单质Fe或者FeCo基合金与单晶MgO(001)结合形成的垂直磁隧道结具有高隧穿磁电阻、高热稳定性、低临界翻转电流的优点,是人们研究的重点。虽然大量的研究取得了丰硕的成果,但是横亘在FeCo/MgO隧道结应用之前的一个重要问题是铁磁层的垂直各向异性难以在较高厚度下保持,提高了材料制备工艺的难度。为此,本文拟研究Fe/MgO中垂直磁各向异性随Fe厚度变化的内在机制,通过优化Fe ...
蔡官志
core
ABSTRACT Enhancing the performance of phosphor materials for wide‐color‐gamut and high‐brightness phosphor‐converted light‐emitting diodes (pc‐LEDs) represents a critical materials challenge. Improving quantum efficiency (QE) under concentration quenching constraints and maintaining thermal stability remain primary objectives.
Yuhan Zhou +3 more
wiley +1 more source
Study on Modification of Wave Absorbing Ability of Silicon Carbide [PDF]
碳化硅具有化学性质稳定、耐高温、耐化学腐蚀、强度高、导热系数高、热膨胀系数小的特点,不仅仅被广泛应用在功能陶瓷、高级耐火材料、磨料及冶金原料等民用领域,还应用于航空航天领域,用作发动机的热端部件。但是,有机先驱体转化法制备的SiC陶瓷电阻率高,对电磁波吸收效率不高。然而,对SiC进行电磁性能改性是该材料具有雷达隐身性能的基础。因此将铁、钴和碳等引入到碳化硅中,提高其介电损耗和磁损耗,进而提高其吸波性能,对发展功能化SiC陶瓷具有重要的意义。 本文选取易石墨化、碳化产率高且价格便宜中间相沥青作为碳源 ...
丁绍楠
core
ABSTRACT CoP has become a research hotspot for supercapacitor electrode materials because of its considerable theoretical capacitance and metalloid nature, but its commercial application remains hampered by structural instability and sluggish ion kinetics.
Gaoliang Wang +8 more
wiley +1 more source
针对一款采用环栅加固方法自主设计研制的BCD(Bipolar-CMOS-DMOS)工艺光电编码器控制电路,开展了电离总剂量(Total Ionizing Dose,TID)辐射效应研究。为揭示编码器辐射损伤机理,设计编码器总体电路及电路中的不同模块,通过对总体电路与模块电路的测试,比较电路各部分输出参数受总剂量辐照的影响规律。结果表明,辐照中编码器电路分模块出现不同程度的输出特性退化,但总体输出在总剂量5 Mrad(Si)范围内依旧保持稳定。结合仿真的方法 ...
许 世萍 +9 more
doaj +1 more source
"fordi før så skreiv æ Å-G". En studie om andreklassingers valg av stavemåter.
The purpose of this master's thesis has been to look at the choices students in Year 2 make when spelling words. The students participating in this research are in the transition between phonological and orthographic writing, and the study will focus on how these students adopt different spelling strategies. The assignment's data material is taken from
openaire +1 more source
Preparation and Electromagnetic Wave Absorbing Property of SiC Fiber /Epoxy Resin Composites [PDF]
本论文对碳化硅(SiC)纤维进行热处理,制备了不同电阻率的SiC纤维;利用不同电阻率的SiC纤维与环氧树脂复合,制备单层、两层和三层复合材料,测试其在X波段下的电磁参数及吸波性能;利用传输线理论,计算预测了纤维电阻率、纤维体积分数、材料厚度和叠层方式对复合材料吸波性能的影响规律,并将实验结果与理论计算结果进行了对比验证。 研究发现,在1000-1500C温度区间,随着热处理温度的升高,SiC纤维的电阻率大幅度降低。当热处理温度达到1500C时,纤维电阻率约为1ohm.cm。随着纤维电阻率的降低 ...
李华展
core
ABSTRACT Developing low‐energy‐input electrocatalytic systems for efficient hydrogen production is crucial for advancing sustainable energy technologies. The overall hydrazine splitting (OHzS) has emerged as a promising strategy to reduce the overall energy consumption by replacing the sluggish oxygen evolution reaction.
Haozhou Chen +13 more
wiley +1 more source
为了探究乙丙橡胶绝缘的表面电痕放电对其极化去极化电流的影响,文中依据IEC 60587:2007模拟乙丙橡胶在实际运行中的表面污秽环境,对乙丙橡胶绝缘试样进行了电痕放电试验,分析了电痕的形成机理,测量了不同电痕腐蚀程度的试样的极化/去极化电流。试验结果表明:绝缘的潮湿污秽区域极易产生泄漏电流,并导致干燥区的形成。在干燥区内引发的重复放电会进一步破坏绝缘表面,从而形成电痕放电。乙丙橡胶的极化电流与其表面电痕腐蚀程度有关:随着乙丙橡胶表面电痕腐蚀程度加重,乙丙橡胶电导率升高,极化电流逐渐增大。
王少飞 +5 more
doaj

