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排序方式: 共有2848条查询结果,搜索用时 15 毫秒
1.
Yun‐hui Wu Zhi‐fu Deng Ze‐fei Peng Rong‐min Zheng Shu‐qi Liu Shu‐ting Xing Jun‐yun Li De‐qun Huang Lan Liu 《Advanced functional materials》2019,29(36)
Low‐melting liquid metal is a hugely promising material for flexible conductive patterns due to its excellent conductivity and supercompliance, especially low‐cost and environmental liquid processing technology. However, the ever‐present fluidity characteristic greatly limits the stable shape and reliability of prepared liquid metal conductive electronics. Herein, a novel solidification strategy of liquid GaIn alloys by Ni doping and heat treatment is first reported, which can efficiently create a solid phase in the liquid metal and provide an effective solution for practical applications. Particularly, the liquid characteristic is preserved for conveniently fabricating different flexible electronic circuits, and then the solidification is carried out on prepared conductive patterns by heat treatment. The solidification mechanism is revealed by the interface chemical reaction between Ni and GaIn, creating the solid phase of intermetallic compound (Ga4Ni3 and InNi3) during heat treatment. Moreover, a biphasic GaInNi can be obtained by regulating the atomic ratio of gallium, indium, and nickel. As a result, the obtained GaInNi possesses extremely low sheet resistance (15 ± 4.5 to 135 ± 2.5 mΩ sq?1) and the variation of ΔR/R0 exhibits low level (0–2) when strained up to 100%, which offers a promising strategy to prepare stretchable and reliable liquid metal electronics. 相似文献
2.
Xiangrong Ma Rui Dang Ning Yang Xiao Li Ya zhang Ying Gong Zhipan Liu Wei Guo Yuanyuan Zhang Chunyan Li 《International Journal of Hydrogen Energy》2021,46(44):22842-22851
The high cost of noble metal catalysts has been a great bottleneck for the catalyst industry. Using the noble metal at a single-atom level for catalytic applications could dramatically decrease the cost. The impacts of single Pt atoms on the photocatalytic performance of Ag3VO4 have been investigated and reported. In this report, single Pt atoms were anchored on the surface of Ag3VO4 (AVO) as a cocatalyst, and the resultant composite photocatalyst has been studied for photocatalytic H2 production from water driven by visible light. The as-prepared AVO particles are hollow nanospheres in the monoclinic phase with a bandgap of 2.20 eV. The light absorption edge of AVO/Pt is slightly red-shifted compared to that of the pristine AVO, indicating more visible light absorption of AVO/Pt. The XPS peaks of Ag, V, and Pt exhibit a significant shift after AVO and Pt get into contact, suggesting the strong interaction between the surface Ag and V atoms, and single Pt atoms. After 3-h illumination, the photocatalytic H2 evolution amount from AVO/Pt is improved up to 1400 μmol, which is 2.8 times that on the bare AVO. Such efficient photocatalytic H2 evolution on AVO/Pt is still maintained after five reaction cycles. The better photocatalytic performance of AVO/Pt has been attributed to the more efficient visible light utilization and the lower interfacial charge transfer resistance, as demonstrated in the DRS and EIS spectra. The presence of the surface Pt atoms also leads to a higher amount of reactive radicals, which could efficiently promote the surface redox reactions. 相似文献
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搭建了以泡沫铜翅片换热器为核心的烟气水分回收实验台,研究了冷却水进口温度、烟气雷诺数及烟气中水蒸气体积分数对该换热器水回收特性和换热特性的影响,基于实验数据,利用多元回归拟合得到对流换热的关联式,其预测值与实验值误差在6%以内。结果表明:水蒸气体积分数增大可以显著提升水回收特性,而冷却水进口温度及烟气雷诺数对其影响很小;冷却水进口温度与烟气雷诺数对换热效率的影响较大,冷却水进口温度与换热效率成反比,烟气雷诺数与之成正比,而水蒸气体积分数对其影响较小;实验获得的最大冷凝水产率为7.68 kg/h,最大冷凝率为56.94%,最大换热效率为96.95%。 相似文献
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采用热力耦合方法对Ti-6Al-4V合金进行了多道次热轧模拟,研究了不同道次温度和等效塑性应变的分布特点。模拟结果表明,轧制过程表面温度低于心部的温度,随轧制道次的增加,表面温度整体表现为降低过程,中心温度整体表现为先升高后降低过程。中心位置比表面位置的等效塑性应变大,表面位置与中心位置的等效塑性应变均随变形道次的增加而增大。结果表明,随着轧制道次的增加,中心显微组织变形大于表面。中心区域组织易于发生动态球化。 相似文献
9.
针对福建省三钢集团有限责任公司棒材厂45钢圆钢热顶锻出现的爆裂、斜向开裂、4角纵向通长开裂、纵向断续微裂4种开裂形式,从表面质量、组织、夹杂物、断口形貌等方面分析了其产生原因。结果表明,钢中存在粗大夹杂物是产生爆裂的主要原因;母材塑性不足是斜向开裂的主要原因;孔型设计不合理带来的皱褶缺陷引起了4角纵向通长开裂;除鳞不净,氧化铁皮压入导致了纵向断续微裂的产生。为此,提出了提高冶炼质量、改进化学成分、调整高压水除鳞工艺、优化孔型设计等措施,显著提高了其热顶锻合格率。 相似文献
10.
Prof. li Xiao-Juan Li li Prof. zhang Xian-Chun Prof. li Jian-Xiu 《Microscopy research and technique》2022,85(2):533-537
In this article, we explored systematically the spore morphology of Pteridaceae by observation of the species distributed in Shandong Province using scanning electron microscopy (SEM). The results showed that the spore morphology of all the species in the family is tetrahedral and trilete. The characters of spore ornamentation are intraspecies stable, but significantly different among species and genera. Spore morphology is significant in exploring the phylogenetic relationships of Pteridaceae as well as in generic and specific delimitations. 相似文献