記述言語：英語   掲載種別：研究論文（学術雑誌）  

<jats:title>Abstract</jats:title><jats:p>The triboelectric series is a generally accepted method for describing the triboelectric effect. It provides a way to control the double face of the ubiquitous triboelectric effect: causes of unpredictable accidents and the resultant surface charge as energy sources. However, previous studies have been biased in solids despite being observed in liquids (liquid‐solid contact electrification). Therefore, a liquid triboelectric series is necessary to be established to manipulate the liquid triboelectric effect according to the appropriate goal. In this study, a liquid triboelectric series is first established to describe the triboelectric properties of each liquid when contact electrification occurs with a solid surface. The liquid triboelectric series covers electrolytes, organic solvents, oxidants, and higher sugar alcohols. Common chemical groups can be derived from the liquid triboelectric series that hydroxyl groups enhance, and benzene groups suppress the liquid triboelectric effect. The results are demonstrated by the amplified efficiency of an energy harvester and particle contamination after surface washing. This study will play a pivotal role in understanding the liquid‐solid contact electrification phenomenon and providing new perspectives on the applications of the liquid triboelectric effect.</jats:p>

DOI： 10.1002/adma.202300699

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担当区分：筆頭著者   記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1016/j.nanoen.2022.107361

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1016/j.applthermaleng.2025.129497

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掲載種別：研究論文（学術雑誌）   出版者・発行元：Wiley  

ABSTRACT

Sensors that capture diverse environmental information are crucial in the elemental technology driving the Fourth Industrial Revolution. However, the trade‐off between sensitivity and working range exhibited by conventional sensors results in limitations when the target stimuli deviate from their predesigned specifications. Thus, single sensors with adjustable performance characteristics must be developed to satisfy functionality requirements in diverse environments. In this study, a Tunable Usability‐Nourished Electrostatic‐based self‐powered force sensor (TUNE sensor) is introduced to overcome the limitations of the fixed detection performance of a single sensor. The tunable sensing performance of the TUNE sensor is achieved via mechano‐guided geometrical adaptation of its three‐dimensional (3D) structure formed via mechanical buckling. Continuous and reversible shape changes in the 3D structure allow modulation of the stiffness of the TUNE sensor, resulting in tunable sensing performance (sensitivity of 0.53~1.08 nC/N and working range of 1.01~0.35 N). The effectiveness of the tunable sensing performance is demonstrated through its implementation in a reconfigurable electronic scale and robotic sensing. This mechano‐guided geometrical adaptation strategy offers the potential for extending the use of sensors in multivariate environments and providing new opportunities for intelligent sensing systems in various applications.

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DOI： 10.1002/eom2.70048

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その他リンク： https://onlinelibrary.wiley.com/doi/full-xml/10.1002/eom2.70048

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Applied Thermal Engineering  

In the United States, water heating, space heating, and space cooling account for 49 % of energy consumption in buildings (residential and commercial). Most space cooling needs and a small portion of space heating needs are met using electrically driven vapor-compression systems. Adequate lubrication of the compressor within these vapor-compression systems is a critical factor in maintaining compressor performance and lifetime. However, oil transport from the compressor to other components in the system can lower the heat transfer coefficient and increase pressure drop. To mitigate this, most compressors rely on coalescing oil separators to separate oil from the refrigerant stream. These oil separators suffer from reduced separation efficiency at high refrigerant mass flow rates. To counter the separation efficiency reduction requires denser and heavier meshes to trap more oil droplets, further decreasing system energy and power densities and increasing pressure drop. Electrostatic separation has been explored as an alternative technology to leverage the tribocharging of oil droplets as they flow through the system. However, these electrostatic parallel-plate systems can be complex. This study demonstrates a hybrid approach to separation of oil from refrigerant by introducing an electric field to traditional coalescing oil separators to capture oil at a higher efficiency and reduce the number of mesh nodes required, ultimately reducing pressure drop. Experimentally, we demonstrate an increase in separation efficiency by a factor up to 7× in the hybrid system when compared to a system with no applied electric field past a critical value for electric field intensity, with a possible 3× reduction in pressure drop—leading to a 1 % enhancement in coefficient of performance. Insights for implementation of this technology into a real HVAC system are also found, such as the limiting behavior in separation efficiency at higher field intensities at a given constant flow rate. The electrostatic separation technology shows significant promise to improve both system performance and lifetime of new and existing vapor-compression systems, increasing the energy density, power density, and heat transfer coefficient of the system while simultaneously lowering their labor cost and carbon footprint of maintenance and replacement.

DOI： 10.1016/j.applthermaleng.2025.127129

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掲載種別：研究論文（学術雑誌）   出版者・発行元：Elsevier BV  

DOI： 10.1016/j.mattod.2025.02.010

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Nano Letters  

While stainless steel offers unique advantages for thermal applications in corrosive environments, it is resilient to traditional nanostructuring techniques such as chemical etching for heat transfer augmentation. In this work, we fabricate a 304L stainless steel alloy using directed energy deposition additive manufacturing, which leads to a metastable microstructure state that facilitates efficient and scalable etching using chloride species. We unveil a two-step etching mechanism that results in the formation of a network of micro- and nanoscale surface structures. This structured surface shows a 5-fold enhancement of the heat transfer coefficient at significantly lower superheat during pool boiling of water, attributed to increased nucleation in suitably sized cavities created by etching. Our work illustrates the vast potential of advances in additive manufacturing techniques for the development of highly efficient and compact thermal systems.

DOI： 10.1021/acs.nanolett.5c01026

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PubMed

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1007/s40684-023-00565-w

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