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Tribological and Thermal Transport of Ag-Vegetable Nanofluids Prepared by Laser Ablation. APPLIED SCIENCES-BASEL 2020. [DOI: 10.3390/app10051779] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Lubricants and fluids are critical for metal-mechanic manufacturing operations as they reduce the friction and wear of tooling and components, and serve as coolants to dissipate the heat generated in these operations. The proper application of these materials improves machine operative life and tooling, and decreases cost, energy, and time consumption for maintenance, damage, repairs, or the need to exchange pieces/components within the machinery. Natural or vegetable-based lubricants have emerged as a substitute for mineral oils, which harm the environment due to their low biodegradability and have negative effects on human health (e.g., causing skin/respiratory diseases). Thus, finding biocompatible and efficient lubricants has become a technology objective for researchers and industry. This study evaluates soybean-, corn-, and sunflower-based lubricants reinforced with silver (Ag) nanostructures by a pulsed laser ablation process. Thermal and tribological evaluations were performed with varying Ag contents, and temperature-dependent behavior was observed. Thermal conductivity improvements were observed for all nanofluids as the temperature and Ag concentration increased (between 15% and 24%). A maximum improvement of 24% at 50 °C and 10 min exposure time of the pulsed laser ablation process for soybean oil was observed. The tribological evaluations showed improvements in the load-carrying capacity of the vegetable oils, i.e., an increase from 6% to 24% compared to conventional materials. The coefficient of friction performance also showed enhancements with Ag concentrations between 4% and 15%.
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Cao Z, Yin Y, Fu P, Li D, Zhou Y, Deng Y, Peng Y, Wang W, Zhou W, Tang D. TiO 2 Nanosheet Arrays with Layered SnS 2 and CoO x Nanoparticles for Efficient Photoelectrochemical Water Splitting. NANOSCALE RESEARCH LETTERS 2019; 14:342. [PMID: 31712915 PMCID: PMC6848439 DOI: 10.1186/s11671-019-3168-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/24/2019] [Accepted: 09/30/2019] [Indexed: 05/14/2023]
Abstract
Converting solar energy into sustainable hydrogen fuel by photoelectrochemical (PEC) water splitting is a promising technology to solve increasingly serious global energy supply and environmental issues. However, the PEC performance based on TiO2 nanomaterials is hindered by the limited sunlight-harvesting ability and its high recombination rate of photogenerated charge carriers. In this work, layered SnS2 absorbers and CoOx nanoparticles decorated two-dimensional (2D) TiO2 nanosheet array photoelectrode have been rationally designed and successfully synthesized, which remarkably enhanced the PEC performance for water splitting. As the result, photoconversion efficiency of TiO2/SnS2/CoOx and TiO2/SnS2 hybrid photoanodes increases by 3.6 and 2.0 times under simulated sunlight illumination, compared with the bare TiO2 nanosheet arrays photoanode. Furthermore, the TiO2/SnS2/CoOx photoanode also presented higher PEC stability owing to CoOx catalyst served as efficient water oxidation catalyst as well as an effective protectant for preventing absorber photocorrosion.
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Affiliation(s)
- Zhou Cao
- Synergetic Innovation Center for Quantum Effects and Application, Key Laboratory of Low-dimensional Quantum Structures and Quantum Control of Ministry of Education, School of Physics and Electronics, Hunan Normal University, Changsha, 410081, People's Republic of China
| | - Yanling Yin
- Synergetic Innovation Center for Quantum Effects and Application, Key Laboratory of Low-dimensional Quantum Structures and Quantum Control of Ministry of Education, School of Physics and Electronics, Hunan Normal University, Changsha, 410081, People's Republic of China
| | - Peng Fu
- Synergetic Innovation Center for Quantum Effects and Application, Key Laboratory of Low-dimensional Quantum Structures and Quantum Control of Ministry of Education, School of Physics and Electronics, Hunan Normal University, Changsha, 410081, People's Republic of China
| | - Dong Li
- Synergetic Innovation Center for Quantum Effects and Application, Key Laboratory of Low-dimensional Quantum Structures and Quantum Control of Ministry of Education, School of Physics and Electronics, Hunan Normal University, Changsha, 410081, People's Republic of China
| | - Yulan Zhou
- Synergetic Innovation Center for Quantum Effects and Application, Key Laboratory of Low-dimensional Quantum Structures and Quantum Control of Ministry of Education, School of Physics and Electronics, Hunan Normal University, Changsha, 410081, People's Republic of China
| | - Yuanwen Deng
- Synergetic Innovation Center for Quantum Effects and Application, Key Laboratory of Low-dimensional Quantum Structures and Quantum Control of Ministry of Education, School of Physics and Electronics, Hunan Normal University, Changsha, 410081, People's Republic of China
| | - Yuehua Peng
- Synergetic Innovation Center for Quantum Effects and Application, Key Laboratory of Low-dimensional Quantum Structures and Quantum Control of Ministry of Education, School of Physics and Electronics, Hunan Normal University, Changsha, 410081, People's Republic of China
| | - Weike Wang
- Synergetic Innovation Center for Quantum Effects and Application, Key Laboratory of Low-dimensional Quantum Structures and Quantum Control of Ministry of Education, School of Physics and Electronics, Hunan Normal University, Changsha, 410081, People's Republic of China
| | - Weichang Zhou
- Synergetic Innovation Center for Quantum Effects and Application, Key Laboratory of Low-dimensional Quantum Structures and Quantum Control of Ministry of Education, School of Physics and Electronics, Hunan Normal University, Changsha, 410081, People's Republic of China
| | - Dongsheng Tang
- Synergetic Innovation Center for Quantum Effects and Application, Key Laboratory of Low-dimensional Quantum Structures and Quantum Control of Ministry of Education, School of Physics and Electronics, Hunan Normal University, Changsha, 410081, People's Republic of China.
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