Search

Your search keyword '"Qiu, Kang‐Wen"' showing total 11 results
Start Over Author "Qiu, Kang‐Wen"
11 results on '"Qiu, Kang‐Wen"'

1. Laser-induced oxygen vacancies in FeCo2O4 nanoparticles for boosting oxygen evolution and reduction

Author

Cun-Ku Dong, Zhe Li, Xi-Wen Du, Rui Zhang, Yan Zhang, Gu-Rong Sheng, Qiu Kang-Wen, Yongjun Chen, Hui Liu, and Cong Xi

Subjects
Materials science, Metals and Alloys, Oxygen evolution, Nanoparticle, chemistry.chemical_element, General Chemistry, Photochemistry, Laser, Oxygen, Redox, Catalysis, Surfaces, Coatings and Films, Electronic, Optical and Magnetic Materials, law.invention, Electron transfer, Fragmentation (mass spectrometry), chemistry, law, Materials Chemistry, Ceramics and Composites
Abstract

FeCo2O4 nanoparticles with abundant oxygen vacancies were produced by laser fragmentation. The oxygen vacancies can lower the thermodynamic energy barriers as well as accelerate the electron transfer, eventually promoting oxygen evolution and reduction reactions simultaneously.

Published
2019

5. Laser-induced oxygen vacancies in FeCo

Author

Qiu, Kang-Wen, Cong, Xi, Yan, Zhang, Rui, Zhang, Zhe, Li, Gu-Rong, Sheng, Hui, Liu, Cun-Ku, Dong, Yong-Jun, Chen, and Xi-Wen, Du

Abstract

FeCo2O4 nanoparticles with abundant oxygen vacancies were produced by laser fragmentation. The oxygen vacancies can lower the thermodynamic energy barriers as well as accelerate the electron transfer, eventually promoting oxygen evolution and reduction reactions simultaneously.

Published
2019

9. Co3O4 Nanoparticles with Ultrasmall Size and Abundant Oxygen Vacancies for Boosting Oxygen Involved Reactions.

Author

Li, Zhe, Zhang, Yan, Feng, Yi, Cheng, Chuan‐Qi, Qiu, Kang‐Wen, Dong, Cun‐Ku, Liu, Hui, and Du, Xi‐Wen

Subjects
NANOPARTICLE size, OXYGEN, TRANSMISSION electron microscopy
Abstract

GLO:OKZ/10mar20:adfm202000364-fig-0002.jpg PHOTO (COLOR): S2 a) Low-resolution transmission electron microscopy image of C-CO nanoparticles. The inset is size distribution pattern with an average particle size ~2.0 ± 0.5 nm. b) High-resolution transmission electron microscopy image of C-CO nanoparticles. gl. [Extracted from the article]

Published
2020
Full Text
View/download PDF

10. Co3O4 Nanoparticles with Ultrasmall Size and Abundant Oxygen Vacancies for Boosting Oxygen Involved Reactions.

Author

Li, Zhe, Zhang, Yan, Feng, Yi, Cheng, Chuan‐Qi, Qiu, Kang‐Wen, Dong, Cun‐Ku, Liu, Hui, and Du, Xi‐Wen

Subjects
FRAGMENTATION reactions, PLATINUM nanoparticles, ALKALINE batteries, SURFACE tension, OXYGEN, OXYGEN reduction, CHARGE exchange, PRECIOUS metals
Abstract

Ultrasmall size and abundant defects are two crucial factors for improving the performance of catalysts. However, it is a big challenge to introduce defects into ultrafine catalysts because of the surface tension and self‐purification effect of the nanoparticles. In the present work, physical laser fragmentation with chemical oxidization reaction is combined to synthesize Co3O4 nanoparticles (L‐CO) with ultrasmall size (≈2.1 nm) as well as abundant oxygen vacancies, thus providing an effective solution to the long‐standing contradiction between the size reduction and defect generation. The ultrasmall particle size allows more catalytic sites to be exposed. The surficial oxygen vacancies enhance the intrinsic activity, while the internal oxygen vacancies improve the electron transfer, and all of these benefits make L‐CO an active and durable bifunctional catalyst for oxygen reduction/evolutions. As the air cathode of zinc–air battery, L‐CO displays excellent rechargeable performance with a power density of ≈337 mW cm−2, outperforming the commercial noble metal couple (Pt/C+RuO2). [ABSTRACT FROM AUTHOR]

Published
2019
Full Text
View/download PDF

11. This title is unavailable for guests, please login to see more information.

Author

Qiu, Kang Wen and Qiu, Kang Wen

Abstract

This thesis aims to investigate how children with different age initiate, maintain, and terminate pretend play through metacommunication. There are three research questions proposed: first, what metacommunicative strategies are used to organize children pretend play? Second, what are the linguistic features of these metacommunicative statements? Finally, does children use of metacommunication display a developmental trend? Participants included in the present study are two Mandarin-speaking children. Both are female. One aged two years and nine months old and the other is four years and five months old. Analytic framework adopted in this thesis is mainly derived from Giffin model. Giffin (1990) advanced a framework comprising seven metacommunicative strategies: enactment, ulterior conversation, underscoring, storytelling, prompting, implicit pretend structuring, and overt proposals to pretend. Results indicate that there are six metacommunicative strategies adopted by children during pretend play: enactment, ulterior conversation, underscoring, prompting, implicit pretend structuring, and overt proposals to pretend. Both children show a strong bias in favor of within-frame metacommunication during pretend play. In addition, there are linguistic features observed in these metacommunicative strategies. These linguistic features display children discrepancies in language development before and after three years old. Besides, how children with different age organize their pretend play through metacommunication is quite different. It has been observed that a four-year-old adopts ulterior conversation and overt proposals to pretend to initiate pretend play. On the other hand, a two-year-old child uses ulterior conversation and implicit pretend structuring as her play initiation strategies. As for play maintaining, older children develop various sub-plots or recapitulate the action format in order to sustain their play. Unlike older children, younger children abi.

Catalog

Books, media, physical & digital resources
See catalog results