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海水作为地球上最丰富的自然资源之一,在实现大规模的电解水制氢方面具有得天独厚的优势。然而,海水中的Cl-、Ca2+和Mg2+等使催化剂在阴极发生腐蚀、毒化或降解,导致其稳定性、活性以及使用寿命显著降低。近年来,为了解决上述问题,人们致力于设计开发廉价的高效稳定析氢反应(HER)催化剂,进而提高电解海水制氢效率。本文首先介绍了电解海水的优势及其HER所面临的挑战,其次从活性和稳定性等方面重点论述了硒化物、硫化物、氮化物以及磷化物等过渡金属基催化剂在电解海水HER中的研究进展,最后总结和展望了电解海水HER催化剂未来的发展前景。 相似文献
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Ultrasound-mediated transdermal drug delivery of fluorescent nanoparticles and hyaluronic acid into porcine skin in vitro 下载免费PDF全文
Transdermal drug delivery(TDD) can effectively bypass the first-pass effect. In this paper, ultrasound-facilitated TDD on fresh porcine skin was studied under various acoustic parameters, including frequency, amplitude, and exposure time. The delivery of yellow–green fluorescent nanoparticles and high molecular weight hyaluronic acid(HA) in the skin samples was observed by laser confocal microscopy and ultraviolet spectrometry, respectively. The results showed that,with the application of ultrasound exposures, the permeability of the skin to these markers(e.g., their penetration depth and concentration) could be raised above its passive diffusion permeability. Moreover, ultrasound-facilitated TDD was also tested with/without the presence of ultrasound contrast agents(UCAs). When the ultrasound was applied without UCAs,low ultrasound frequency will give a better drug delivery effect than high frequency, but the penetration depth was less likely to exceed 200 μm. However, with the help of the ultrasound-induced microbubble cavitation effect, both the penetration depth and concentration in the skin were significantly enhanced even more. The best ultrasound-facilitated TDD could be achieved with a drug penetration depth of over 600 μm, and the penetration concentrations of fluorescent nanoparticles and HA increased up to about 4–5 folds. In order to get better understanding of ultrasound-facilitated TDD, scanning electron microscopy was used to examine the surface morphology of skin samples, which showed that the skin structure changed greatly under the treatment of ultrasound and UCA. The present work suggests that, for TDD applications(e.g., nanoparticle drug carriers, transdermal patches and cosmetics), protocols and methods presented in this paper are potentially useful. 相似文献
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Zinc-air batteries (ZABs) are regarded as one of the most promising candidates for a new generation of advanced energy conversion and storage devices,while the inferior activity and stability of air cathode electrocatalysts largely hinder the widespread application of ZABs. The extensive efforts for exploring and designing high active yet stable air cathode catalysts is,therefore,indispensable for the improvement of ZABs performance. Recently,carbon-encapsulated iron-based nanoparticles have been reported to exhibit excellent oxygen catalytic performance on account of their resistance to corrosion,oxidation,and aggregation under harsh conditions,and have been widely used as cathode materials for ZABs. As a result,we systematically summarize the applications of carbon-encapsulated transition metal iron-based materials as cathode catalysts for ZABs. In this review,the basic principle of ZABs and challenges faced by air cathode catalysts are firstly expounded. Then, the research progress of the carbon-encapsulated iron-based nanoparticles electrocatalysts (such as iron-based and its alloy,carbide,oxide and phosphide,et al.) are emphatically discussed and analyzed. Finally,the future development perspectives of carbon-encapsulated iron-based electrocatalysts in the applications of ZABs are put forward. © 2022, Science Press (China). All rights reserved. 相似文献
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多孔碳材料的模板法制备、活化处理及储能应用 总被引:2,自引:0,他引:2
简要介绍了广义模板法制备多孔碳材料的研究现状,并进一步阐述了应用传统活化法对模板法制备的多孔碳材料进行结构调控. 最后,详细介绍了多孔碳材料在氢气吸附以及超级电容器用电极材料等储能领域的应用. 相似文献
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