Results 91 to 100 of about 22,800 (217)
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
wiley +1 more source
环氧树脂由于其优异的绝缘密封性能被广泛应用于干式空心电抗器,然而在湿热环境中环氧树脂易吸水受潮导致材料性能劣化,严重影响设备的安全稳定运行,有效的寿命预测方法或技术对于提高设备可靠性、减少经济损失具有重要意义,因此文中研究了基于活化能的环氧树脂寿命预测方式。首先对环氧树脂材料进行湿热老化,研究老化前后表面样貌和化学结构的变化,实验发现老化后环氧树脂表面出现许多微孔,吸收电流和极化电荷均随吸水率的增大而增大,老化过程中环氧树脂发生酯基的水解;接着用Kissinger法和Flynn-Wall ...
张国平 +6 more
doaj
New Type of One-Dimensional Graphene Nanomaterials -Preparation and Application of Graphene Nanotubes [PDF]
一维碳纳米材料包括碳纳米管和一维石墨烯纳米材料(石墨烯纳米带和石墨烯纳米卷),由于其独特的结构和物理、化学性质,具有很大的潜在应用价值。但是高昂的制备成本和复杂的制备流程限制了一维碳纳米材料的广泛应用。因此,通过利用一种低成本、简单的方法制备一维石墨烯纳米材料是现阶段有关一维碳纳米材料研究的重点。氧化石墨烯因为其结构中带有大量的含氧官能团,使其具有与一些金属(如铜、铁等)自发发生氧化还原反应的能力。因此利用氧化石墨烯与金属铜可自发发生氧化还原反应的特点,以铜纳米线作为模板,可原位制备石墨烯纳米管 ...
胡波
core
ABSTRACT High‐entropy alloys (HEAs) have attracted considerable interest from researchers owing to their tunable chemical compositions, exceptional structural stability, and promising catalytic properties. However, their large‐scale application is often hindered by complex manufacturing techniques and poor durability.
Sheng Guo +9 more
wiley +1 more source
白鹤是世界瞩目的珍贵动物。它是生活在浅水沼泽中一种大型的迁徙性涉禽,由于白鹤对生存环境的选择和要求,较其他生活习性相似的种类更为严格,换句话,也就是适应环境变化的能力较差,不能适应由于人类经济活动造成的环境急剧变化。因此 ...
丁文宁
doaj
Solution synthesis and characterization of nickel nanosheets [PDF]
具有形状各向异性的镍纳米晶在催化、磁记录、生物、电极材料等诸多领域具有重要的应用价值,因此探索一种简便可靠的合成方法来制备尺寸和形貌可控的镍纳米晶具有重要的研究意义。本论文通过有机液相法合成出了镍纳米片,研究了不同的制备参数对镍纳米晶的形貌、尺寸和结构的影响,并表征了其磁学性质和催化对硝基酚还原的性能。 本文首先以油胺作为溶剂和还原剂,乙酰丙酮镍作为镍前驱体,六羰基钨作为形核诱导剂,合成出了尺寸可控的镍纳米片。在较低的反应温度(160℃)和较短的保温时间下可以得到尺寸为15nm的镍纳米片 ...
汪志超
core
ABSTRACT Multi‐element Prussian blue analog (PBA) nanocomposites have attracted wide attention for their superior characteristics to single‐functional nanomaterials in extensive applications of diagnosis and therapy. In this study, a novel hollow nanocomposite was designed and fabricated by embedding S2− and Ag nanoparticles into a NiCuMnFe (PBA).
Tao Ji +7 more
wiley +1 more source
丝裂源活化的蛋白激酶(mitogen-activatedprotein20kinases,MAPKs)家族参与细胞生长、增殖、分化和凋亡等重要过程。MAPK家族成员p42/44MAPK(Erk1/2)在生长因子、细胞因子、营养物质和能量刺激下活化,促进细胞增殖或抵抗凋亡;Erk1/2分子中Thr202和Tyr204位氨基酸残基的磷酸化是其活化的标志[1 ...
潘敏, 王海, 张铎, 李妍
doaj
ABSTRACT Skin wound injuries are often accompanied by bacterial infections and severe inflammation. Especially, M1‐type macrophages at the wound site can trigger a cascade of inflammatory responses, mediating a vicious cycle of inflammation. Meanwhile, hypoxia further exacerbates vascular damage and constriction in the wound microenvironment, thereby ...
Xianfeng Wang +6 more
wiley +1 more source
通过盆栽试验,研究化肥减量10%~30%条件下,配施与所减化肥相同用量的2种生物有机肥对油菜生理代谢、产量、土壤生物学特性和养分含量的影响,系统的阐述了生物有机肥应用于蔬菜生产的优势所在。结果表明:减量化肥配施生物有机肥可促进油菜生长,提高油菜叶片内叶绿素含量和根系活力,同时增强了油菜叶片和根系内抗氧化酶(SOD、POD、CAT)活性,降低了过氧化物质含量(MDA、O2?
宋以玲 +6 more
doaj

