49 results on '"Li, Chengming"'
Search Results
2. Explore the growth mechanism of high-quality diamond under high average power density in the MPCVD reactor
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Yang, Zhiliang, An, Kang, Feng, Xurui, Liu, Yuchen, Guo, Zhijian, Wei, Junjun, Chen, Liangxian, Liu, Jinlong, and Li, Chengming
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- 2024
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3. Influence of room-temperature oxidation on stability and performance of reactively sputtered TaN thin films for high-precision sheet resistors
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Zhang, Mingzhen, Wang, Yue, Song, Shangzhi, Guo, Ruiqiang, Zhang, Wenbin, Li, Chengming, Wei, Junjun, Jiang, Puqing, and Yang, Ronggui
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- 2024
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4. Handcrafted silver substrates boost surface plasmon resonance for ultra-sensitive lipid analysis
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Wang, Yunpeng, Xu, Xiaoying, Li, Yuting, Li, Chengming, Wang, Xiaotong, Wu, Jing, and Li, Yang
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- 2024
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5. Deposition of uniform diamond films on three dimensional Si spheres by using faraday cage in MPCVD reactor
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Yang, Zhiliang, Liu, Yuchen, Guo, Zhijian, Wei, Junjun, Liu, Jinlong, Chen, Liangxian, and Li, Chengming
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- 2024
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6. Comparison and analysis of properties of transparent and translucent diamonds prepared via DC arc plasma jet CVD
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Shao, Siwu, Liu, Peng, Ye, Sheng, Chen, Liangxian, Zhang, Jianjun, Wei, Junjun, Liu, Jinlong, and Li, Chengming
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- 2024
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7. The uniform and robust 8-inch CVD diamond plate generated by dual-magnetic field controlled DC Jet CVD
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Liu, Peng, Shao, Siwu, Yang, Zhiliang, An, Kang, Ye, Sheng, Huang, Ke, Cheng, Liangxian, Zhang, Jianjun, Wei, Junjun, Liu, Jinlong, and Li, Chengming
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- 2024
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8. A turn-on fluorescent probe for lipid-targeting imaging in human arterial aneurysm and fibrocalcific stenotic aortic valve
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Liu, Qi, Zhuang, Weihua, Chen, Jingruo, Li, Shufen, Li, Chengming, Ma, Di, and Chen, Mao
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- 2023
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9. A pH-responsive nanoplatform with aggregation-induced emission features for lipid droplet imaging in atherosclerosis
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Ma, Di, Zhuang, Weihua, Liu, Qi, Chen, Jingruo, Li, Chengming, Li, Shufen, and Chen, Mao
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- 2023
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10. Aggregation-induced bioprobe for plasma membrane-specific imaging and photodynamic cancer cell ablation
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Wang, Yinchan, Zhuang, Weihua, Wu, Sisi, Duan, Zhenyu, Li, Shufen, Chen, Jingruo, Zhou, Linsen, Zhou, Yongjie, Li, Chengming, and Chen, Mao
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- 2023
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11. Aggregation-induced emission fluorescent probes for lipid droplets-specific bioimaging of cells and atherosclerosis plaques
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Zhang, Ying, Zhuang, Weihua, Chen, Jingruo, Li, Chengming, Li, Shufen, and Chen, Mao
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- 2023
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12. High charge collection efficiency detector based on plasma purified high-quality diamond
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Mu, Lianxi, Su, Kai, Hu, Tingting, Liu, Jinlong, Zhang, Jinfeng, Chen, Liangxian, Wei, Junjun, Ouyang, Xiaoping, and Li, Chengming
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- 2022
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13. Structural transformation of C+ implanted diamond and lift-off process
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Zhu, Xiaohua, Chan, Siyi, Yuan, Xiaolu, Tu, Juping, Shao, Siwu, Jia, Yuwei, Chen, Liangxian, Wei, Junjun, Liu, Jinlong, Kawarada, Hiroshi, and Li, Chengming
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- 2022
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14. Exploring three-point-bending fracture toughness of thick diamond films from different directions
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An, Kang, Liu, Peng, Shao, Siwu, Li, Haixia, Yang, Zhiliang, Zhang, Shuai, Li, Shiyu, Huang, Yabo, Liu, Jinlong, Chen, Liangxian, Wei, Junjun, Zheng, Yuting, Liu, Qing, Liu, Fengbin, and Li, Chengming
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- 2022
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15. Molecular Engineering of g-C3N4 with Dibenzothiophene Groups as Electron Donor for Enhanced Photocatalytic H2-Production
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Tao, Shanren, Wan, Sijie, Huang, Qinyang, Li, Chengming, Yu, Jiaguo, and Cao, Shaowen
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- 2022
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16. The 7-in. freestanding diamond thermal conductive film fabricated by DC arc Plasma Jet CVD with multi-stage magnetic fields
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Huang, Yabo, Chen, Liangxian, Shao, Siwu, Huang, Ke, An, Kang, Zheng, Yuting, Liu, Jinlong, Wei, Junjun, and Li, Chengming
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- 2022
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17. High temperature surface graphitization of CVD diamond films and analysis of the kinetics mechanism
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Yan, Xiongbo, Wei, Junjun, An, Kang, Liu, Jinlong, Chen, Liangxian, Zheng, Yuting, Zhang, Xiaotong, and Li, Chengming
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- 2021
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18. Evolution of growth characteristics around the junction in the mosaic diamond
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Zhu, Xiaohua, Liu, Jinlong, Shao, Siwu, Tu, Juping, Huang, Yabo, Bi, Te, Chen, Liangxian, Wei, Junjun, Kawarada, Hiroshi, and Li, Chengming
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- 2021
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19. Effect of grain boundary on polycrystalline diamond polishing by high-speed dynamic friction
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Liang, Yifan, Zheng, Yuting, Wei, Junjun, Jia, Xin, Zhu, Xiaohua, An, Kang, Liu, Jinlong, Chen, Liangxian, and Li, Chengming
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- 2021
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20. Effect of oxygen/argon ratio on microstructure, compositon and optical properties of erbium oxide anti-reflection films on CVD diamond.
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Huang, Yabo, Li, Chengming, Chen, Liangxian, Liu, Jinlong, Wei, Junjun, Wang, Xulei, and Zhu, Xiaohua
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ANTIREFLECTIVE coatings , *ERBIUM , *OXIDE coating , *DIAMOND films , *OPTICAL properties , *ARGON - Abstract
Optical erbium oxide (Er 2 O 3) films were prepared by radio frequency (RF) magnetron sputtering to improve the infrared (IR) transmittance of chemical vapor deposition (CVD) diamond. This study aims to analyze the microstructure, composition and optical properties of Er 2 O 3 anti-reflection films at various oxygen/argon ratios. Atomic force microscopy (AFM) analysis was used to detect the surface morphology of chemical oxidation CVD diamond and Er 2 O 3 films. The surface roughness of Er 2 O 3 films decreased with an increase in the oxygen/argon ratio. The crystalline structure of Er 2 O 3 films was analyzed by using X-ray diffraction. Meanwhile, a gradual decrease was observed when the crystallite size and its strain were calculated. This was due to the transformation of partial phases from monoclinic to cubic structures. The chemical composition of Er 2 O 3 films was analyzed by X-ray photoelectron spectroscopy (XPS). The surface of Er 2 O 3 films underwent a transformation from the unstable structure of nonstoichiometric Er 2 O 3-x to the stable structure of Er 2 O 3 with an increase in the level of oxygen. Defect behavior was determined by transmission electron microscopy (TEM). Specifically, dislocation and twinning were observed at a high oxygen/argon ratio, which was mainly attributed to the competitive growth of polycrystalline Er 2 O 3 films. The optical constants of Ψ and △ were shifted to lower wavelengths with increase oxygen/argon ratio. The maximum transmittance of the Er 2 O 3 /diamond film was 79% in the long-wavelength infrared (LWTR) range of 8–12 μm at an oxygen/argon ratio of 1:35. This value was significantly higher than that of the high oxygen/argon ratio. The present study concludes that a low oxygen/argon ratio promotes the growth and IR transmittance of Er 2 O 3 films. [ABSTRACT FROM AUTHOR]
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- 2023
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21. Corrigendum to “High charge collection efficiency detector based on plasma purified high-quality diamond” [Diam. Relat. Mater. 130 (2022) 109527]
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Mu, Lianxi, Su, Kai, Hu, Tingting, Liu, Jinlong, Zhang, Jinfeng, Chen, Liangxian, Wei, Junjun, Ouyang, Xiaoping, and Li, Chengming
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- 2023
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22. The impact of climate change on corporate ESG performance: The role of resource misallocation in enterprises.
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Li, Chengming, Tang, Wei, Liang, Feiyan, and Wang, Zeyu
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ORGANIZATIONAL performance , *REAL economy , *RESOURCE curse , *CITIES & towns , *BUSINESS enterprises , *CLIMATE change - Abstract
In recent years, the negative consequences of climate change have gradually spread to the real economy sector, which affects enterprise output, increases enterprise costs, and thus inhibits the sustainable development of enterprises. Still, it is not clear whether corporate resource misallocation will reinforce the effect. Therefore, using the data of A-share listed companies in 2011–2021, this paper investigates the impact of climate change on corporate environmental, social, and governance (ESG) performance. According to empirical results, climate change significantly inhibits corporate ESG performance. It also found that continuously eliminating internal and external resource misallocation helps alleviate the adverse effects of climate change on ESG performance. Furthermore, compared with enterprises in non-resource-based cities, climate change will significantly improve corporate ESG performance in resource-based cities, indicating that the adaptive behavior caused by climate change has partially broken the resource curse phenomenon. Additionally, mature and large-scale enterprises mitigate the negative effects better, and external pressure from the public environmental and analysts' attention can motivate companies to improve their ESG performance. The research enriches the research on the impact of climate change on corporate ESG performance and provides a reference basis for enterprises to cope with climate risks. [ABSTRACT FROM AUTHOR]
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- 2024
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23. Damage identification for pile foundation in high-piled wharf using composite energy factors driven by dynamic response under wave impact excitation.
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Li, Chengming, Wang, Qiming, Zhu, Ruihu, Zhu, Yongzhong, and Hu, Yan
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BUILDING foundations , *IDENTIFICATION , *ENERGY consumption , *SIGNAL reconstruction - Abstract
Exploring dynamic response-based damage identification under wave excitation is important for establishing a health monitoring system. In our previous study, we analyzed the characteristics of the rigid-body dynamic response and successfully employed them to identify the damage location of a pile foundation. Nevertheless, some recent researches show that the local flexural response resulting from wave impact has stronger energy performance. Therefore, this paper constructed a new damage identification method by making full use of energy and phase slope of the local flexural response. Firstly, a novel frequency domain clustering algorithm based on the Sub-peaks Suppression of Power Spectral Density Method (SSPSDM) was proposed to address the challenge of mode mixing in signal decomposition. Subsequently, the new composite energy factors were developed by combining both energy and phase of the local flexural response to enhance the sensitivity and robustness of damage identification. Finally, the method was validated using the acceleration signals from a laboratorial high-piled wharf model. The results show that the method can effectively extract the damage feature sub-signal and the composite energy factor based on phase slope enables better identification of the damage location and degree, enhancing the accuracy of the damage assessment process. • A frequency domain clustering method was proposed to extract different responses. • The Sub-peaks Suppression of Power Spectral Density Method was proposed. • The composite energy factors with better identification effect were proposed. • The effects of decomposition algorithms for damage identification were compared. [ABSTRACT FROM AUTHOR]
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- 2024
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24. Low-carbon strategy, entrepreneurial activity, and industrial structure change: Evidence from a quasi-natural experiment.
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Li, Chengming, Liang, Feiyan, Liang, Yinhe, and Wang, Zeyu
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CITIES & towns , *ADAPTIVE natural resource management , *SUSTAINABLE development , *ENERGY conservation , *URBAN policy - Abstract
As the top carbon emitter in the world, a key step taken by China to encourage energy conservation, pollution reduction, and environmentally friendly development is the low-carbon city pilot (LCCP) policy, which has made important contributions to reducing global emissions. The LCCP policy aims to conserve energy and reduce emissions, inexorably influence many facets of the economic system because it is a well-rounded environmental management strategy. So, has this policy impacted the entrepreneurial activity of the region while achieving green development? Using panel data from China's 279 cities from 2002 to 2019, this article employs the difference-in-differences (DID) model to assess the influence of the LCCP policy on urban entrepreneurial activity. Through the results, the LCCP policy generally inhibits entrepreneurial activity. But the level of green innovation can alleviate this inhibitory effect. Based on the heterogeneity analysis, the LCCP policy exerts a more pronounced inhibitory effect on entrepreneurial activity in central and western regions, resource-based cities, and non-central cities. Further, the LCCP policy inhibits entrepreneurial activity in high-carbon industries while encouraging entrepreneurial activity in emerging industries, resulting in industrial structure change and upgrading. This paper supplies new empirical evidence for the effects of the LCCP policy on entrepreneurial activity and industrial structure change. [ABSTRACT FROM AUTHOR]
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- 2023
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25. Phyllanthus emblica Linn. fruit polyphenols improve acute paradoxical sleep deprivation-induced cognitive impairment and anxiety via Nrf2 pathway.
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Li, Chengming, Long, Pan, He, Mengshan, Han, Fei, Jiang, Wei, Li, Yubo, Hu, Yonghe, and Wen, Xudong
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[Display omitted] • Acute paradoxical SD can lead to cognitive impairment and anxiety. • PEFPs, a promising food homologous phytotherapy for maintaining brain health. • PEFPs effectively alleviated acute paradoxical SD-induced behavioral abnormalities. • PEFPs improve cognitive impairment and anxiety by activating the Nrf2 signaling pathway. • PEFPs are attractive nutraceutical ingredients for preventing cognitive impairment and anxiety associated with sleep loss. Phyllanthus emblica Linn. fruit that primarily contains many polyphenols, have been considered homologous food for centuries and have been used as a remedy for a variety of ailments, including maintaining brain function. It is, however, unclear what is the mechanism of protective action of Phyllanthus emblica Linn. fruit polyphenols (PEFPs) against cognitive impairment and anxiety induced by acute paradoxical sleep deprivation (SD). Behavioral abnormalities induced by acute paradoxical SD were effectively alleviated by PEFPs, which also prevented histopathological and morphological damage to hippocampal neurons. Acute paradoxical SD-induced cognitive impairments and anxiety are treated by PEFPs through modulating a variety of biological functional modules, such as oxidative stress, inflammation/immune, cell proliferation and differentiation, metabolism, and neurotransmitter signaling. Further results showed that PEFPs markedly counteracted oxidative stress damage and neuroinflammation by activating the Nrf2 pathway. In summary, PEFPs are attractive nutraceutical ingredients for preventing cognitive impairment and anxiety associated with sleep loss. [ABSTRACT FROM AUTHOR]
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- 2023
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26. Immobilization of heavy metals in ceramsite prepared using contaminated soils: Effectiveness and potential mechanisms.
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Li, Chengming, Song, Bing, Chen, Zhiliang, Liu, Zequan, Yu, Lei, Zhi, ZeJian, Zhao, Yan, Wei, Hong, and Song, Min
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HEAVY metals , *SOILS , *SANDY soils , *SOIL temperature , *THERAPEUTIC immobilization , *CLAY soils - Abstract
Heavy metal contaminated soils pose a serious threat to the environment, and preparing ceramsite using contaminated soils was proposed as an effective method to address this threat in this study. Specifically, two typical soils (i.e., contaminated clay and sandy soil) were mixed with different ratios and calcined at temperature 1000–1200 °C to prepare ceramsite. Special attentions were paid to evaluating the immobilization of heavy metals in ceramsite and identifying the corresponding immobilization mechanisms. Using the leachability of heavy metals from ceramsite as evaluation criteria, the optimum mixing ratio of clay/sandy soil and sintering temperature were determined as 0.6:0.4 and 1200 °C. Moreover, based on the spectroscopic characterizations and thermodynamic calculation, high sintering temperature well facilitated the liquid phases formation, promoting the reactions between heavy metals and aluminosilicates and the valence state conversion of heavy metals. Accordingly, heavy metals were well immobilized in ceramsite by forming thermodynamically stable minerals, being encapsulated in solid matrix, and transforming to valence states with low mobility. The leaching conditions including pH and temperature had minimal effect on the immobilization of heavy metals in ceramsite. In summary, ceramsite prepared by contaminated soils was environmentally friendly and had good potential in engineering application as building materials. [Display omitted] • Co-utilization of polluted clay and sandy soil for ceramsite production is presented. • The optimum ratio of clay/sandy soil and sintering temperature are 0.6:0.4 and 1200 °C. • The immobilization effectiveness of heavy metals in ceramsite is evaluated. • The immobilization mechanism of heavy metals in ceramsite is determined. [ABSTRACT FROM AUTHOR]
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- 2023
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27. A new model for the segmentation, propagation and linkage of the Tan-Lu fault zone, East Asia.
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Li, Chengming, Zhang, Changhou, and Cope, Tim D.
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FAULT zones , *GEOLOGICAL mapping , *GEOLOGICAL maps , *URANIUM-lead dating , *OROGENIC belts , *ASIAN history - Abstract
[Display omitted] • The Tan-Lu Fault formed by coalescence of two kinematically independent segments. • The northern and southern Tan-Lu faults exhibit contrasting displacement profiles. • The northern and southern Tan-Lu faults propagated in opposite directions. • Southward indentation of the Siberian craton initiated the northern Tan-Lu Fault. • The northern and southern Tan-Lu faults linked in the early Late Jurassic. The Tan-Lu fault zone (TLF) is a major strike-slip fault with a long and complex history in East Asia, whose evolution provides a new perspective on the formation of large-scale faults (>1000 km long). Fault displacement analysis, geological mapping and U-Pb LA-ICP-MS dating have been performed to understand the evolution of the TLF. Along-strike displacement variation reveals that the TLF consists of two kinematically independent segments, the northern and southern TLF, with opposite long-term propagation directions. Structural and geochronological studies in the eastern Yanshan belt, located around the linkage area of the southern and northern TLF, indicate that NNE-trending sinistral strike-slip faults initiated at 167–164 Ma and were reactivated at 124–121 Ma. Structural analysis suggests that these early NNE-trending strike-slip faults transferred sinistral motion along the northern TLF into southward thrusting along the Yanshan belt, representing the Middle Jurassic southern termination of the northern TLF. Our studies suggest that the through-going TLF formed when the younger southward-propagating northern TLF merged with the older northward-propagating southern TLF in the Late Jurassic. A new model is thus proposed for the Mesozoic evolution of the TLF. The initiation and southward propagation of the northern TLF is interpreted to have resulted from the southward indentation of the Siberian craton into the amalgamated Central Asian Orogenic Belt and North China block. The divergent mega-splays of the northern TLF likely resulted from westward-younging formation during the clockwise rotation of northeast Asia. Coalescence of two genetically unrelated faults could be an alternative mode for large-scale fault formation. [ABSTRACT FROM AUTHOR]
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- 2023
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28. Specific lipid droplet imaging of atherosclerotic plaques and fatty liver using an imidazole-based fluorescence probe.
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Li, Chengming, Zhuang, Weihua, Wang, Yinchan, Li, Shufen, Chen, Jingruo, Zhou, Linsen, Liao, Yanbiao, Chen, Mao, and You, Jingsong
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ATHEROSCLEROTIC plaque , *FATTY liver , *INTRAVASCULAR ultrasonography , *FLUORESCENCE , *SUNFLOWER seed oil , *INTRACELLULAR tracking , *IMIDAZOLES - Abstract
Selective labelling and high-fidelity tracking of intracellular lipid droplets (LDs) can provide direct insight into pathological processes associated with abnormal lipid metabolism and therefore are of great value. We herein present a novel imidazole-based probe, TITM , which shows the aggregation-induced emission property and a remarkable fluorescence increase in sunflower oil than in water. With the advantages of good lipophilicity, biocompatibility, and LDs-targeted specificity, TITM allows the real-time and long-term tracking of dynamic LDs in living cells with high-resolution imaging performance. By establishment of LDs-related atherosclerosis (AS) and fatty liver mouse model, the imaging performance of TITM at pathological tissue level is well studied to show impressive selectivity and resolution. [Display omitted] • An imidazole-based probe is disclosed to show a remarkable fluorescence increase in sunflower oil than in water. • The probe allows real-time and long-term tracking of lipid droplets in living cells with high-resolution imaging. • The fluorescence probe shows good biocompatibility and photostability. • The probe can visualize abnormal lipid droplets accumulation in mouse atherosclerotic plaques and fatty liver tissues. [ABSTRACT FROM AUTHOR]
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- 2022
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29. Analysis of the spatiotemporal evolution of the coastline of Jiaozhou Bay and its driving factors.
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Cai, Haolin, Li, Chengming, Luan, Xueke, Ai, Bo, Yan, Luyan, and Wen, Zhen
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COASTAL zone management ,COASTS ,COASTLINE changes ,SUSTAINABLE development - Abstract
Studying the spatiotemporal changes in coastlines and the underlying mechanisms is important for the rational development and utilization of coastal resources and sustainable economic development. For the first time, this study analyzes twenty years of spatiotemporal changes in the coastline of Jiaozhou Bay (JB), Qingdao, by integrating high-resolution remote sensing images from Google Maps and Landsat time series data at five-year intervals from 2000 to 2020. Five coastlines were extracted using the normalized difference water index and Otsu threshold segmentation method. The index of coastline type diversity (ICTD), index of coastline utilization degree (ICUD), and end point rate were applied to the systematic study of the evolution of the coastline of JB for the first time. The results show that the total length of coastline decreased, with the natural coastline accounting for only approximately 10% of the sharp decrease in the first five years and slow increase in the last 15 years. The ICTD was >0.7, and the ICUD increased from 231.7 to 261.5, indicating an increase in the influence of humans. The coastline also moved seaward with an average accretion rate of 47.5 km/year, resulting in a 24.5 km
2 reduction in the area of the bay over the 20 years. This was caused by human activities such as port construction. In addition, the degree of correlation between coastline changes and socioeconomic factors was analyzed using grey correlation analysis. Based on this, the forces driving the changes to the coastline were explored, and suggestions for coastal zone management were proposed. [ABSTRACT FROM AUTHOR]- Published
- 2022
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30. A partitioned collapse method for long and narrow patches.
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Li, Chengming, Yin, Yong, Wu, Pengda, and Wu, Wei
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GEOGRAPHIC boundaries , *STATISTICS , *CONFLICT of interests , *DATA analysis , *GENERALIZATION - Abstract
Collapse is a basic generalization operation in land-use data multi-scale representation. It is a compute-intensive operation and involves complex topological transformations. A feasible way to improve the computation efficiency is to adopt a parallel strategy, which means that the collapse of a large spatial range of long and narrow (LN) patches via a partitioning-based approach. However, many topological inconsistencies occur around the partition-cell boundaries. Hence, we propose a partitioned collapse method for LN patches and focus on the reconstruction problem of topological inconsistencies. First, topological inconsistencies were classified into four patterns based on their morphological characteristics. Second, for each of these patterns, a corresponding algorithm was formulated to reconcile the topological inconsistencies. Finally, our approach was validated using the national geographical condition data of Chishui City, Guizhou Province. The experiment results show that our method generates smooth split lines from land-use patches by effectively eliminating topology inconsistency patterns near the partition-cell boundary lines and is 8.7 times more efficient than the traditional unpartitioned method within a city region. • Partition methodology of collapse operation for long and narrow patches generalization. • Topology consistency maintenance during partitioned collapse operation. • Reliability and efficiency analysis by comparing with an un-partitioned collapse method with a small-area data. • Efficiency and superiority verification by statistical analysis with a large-area data. • No potential conflict of interest was reported by the authors. [ABSTRACT FROM AUTHOR]
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- 2022
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31. Structural evolution and self-destructive behavior of Mo/Ti transition layers during free-standing diamond-film preparation.
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Shao, Siwu, Liu, Peng, Ye, Sheng, An, Kang, Chen, Liangxian, Zhang, Jianjun, Wei, Junjun, Liu, Jinlong, Ouyang, Xiaoping, and Li, Chengming
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SELF-destructive behavior , *DIAMOND crystals , *VACUUM arcs , *DIAMOND films , *TRANSITION metals , *CHEMICAL vapor deposition , *SUBSTRATES (Materials science) - Abstract
Graphite-based metal transition-layer substrates hold great potential for preparing large-area diamond films and achieving crack-free release. In this study, a five-inch crack-free free-standing diamond film was prepared on a graphite substrate with a sacrificial Mo/Ti double-layer transition layer using direct-current arc plasma jet chemical vapor deposition (DC jet CVD). The interfacial bonding and diffusion behavior between the diamond and the transition layers were investigated. The effect of abundant metal particles and elemental diffusion between layers on film adhesion and stress release are discussed and analyzed. The surface of Ti layer prepared by the multi-arc ion-plating contains numerous metal particles that provide a template for the fine-crystalline Mo layer. Metal particles are encapsulated and embedded in the diamond and act as anchors that ensure the stability of the substrate–diamond bond during high-temperature deposition. After deposition, those metal particles act as weak points and play crucial stress-release roles. Mutual elemental diffusion occurs between the Ti, Mo, and diamond layers. Ti penetrates the Mo layer to form a continuous 140-nm-thick thin layer during the initial deposition period, facilitating diamond nucleation. Carbon from the plasma and diamond diffuses into the metal transition layer. Thermal stress generated between the diamond and the graphite substrate is released by destroying the metal transition layer with high thermal expansion coefficient and low elastic modulus during cooling from the deposition temperature. Cracks rapidly propagate along the interface between destroyable transition layers and graphite substrate, which results in the liftoff of a fully crack-free diamond film. [Display omitted] [ABSTRACT FROM AUTHOR]
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- 2024
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32. Computed Tomography-Based Delta-Radiomics Analysis for Discriminating Radiation Pneumonitis in Patients With Esophageal Cancer After Radiation Therapy.
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Wang, Lu, Gao, Zhenhua, Li, Chengming, Sun, Liangchao, Li, Jianing, Yu, Jinming, and Meng, Xue
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CANCER radiotherapy , *RADIATION pneumonitis , *ESOPHAGEAL cancer , *FEATURE extraction , *COMPUTED tomography , *RESEARCH , *RESEARCH methodology , *RETROSPECTIVE studies , *MEDICAL cooperation , *EVALUATION research , *COMPARATIVE studies , *RADIATION doses , *STATISTICAL models , *ESOPHAGEAL tumors - Abstract
Purpose: Our purpose was to construct a computed tomography (CT)-based delta-radiomics nomogram and corresponding risk classification system for individualized and accurate estimation of severe acute radiation pneumonitis (SARP) in patients with esophageal cancer (EC) after radiation therapy.Methods and Materials: Four hundred patients with EC were enrolled from 2 independent institutions and were divided into the training (n = 200) and validation (n = 200) cohorts. Eight hundred fifty radiomics features of lung were extracted from treatment planning images, including the positioning CT before radiation therapy (CT1) and the resetting CT after receiving 40 to 45 Gy (CT2). The longitudinal net changes in radiomics features from CT1 to CT2 were calculated and defined as delta-radiomics features. Least absolute shrinkage and selection operator algorithm was performed to features selection and delta-radiomics signature building. Integrating the signature with multidimensional clinicopathologic, dosimetric, and hematological predictors of SARP, a novel CT-based delta-radiomics nomogram was established according to multivariate analysis. The clinical application values of nomogram were both evaluated in the training and validation cohorts by concordance index, calibration curves, and decision curve analysis. Recursive partitioning analysis was used to generate a risk classification system.Results: The delta-radiomics signature consisting of 24 features was significantly associated with SARP status (P < .001). Incorporating it with other high-risk factors, Subjective Global Assessment score, pulmonary fibrosis score, mean lung dose, and systemic immune inflammation index, the developed delta-radiomics nomogram showed increased improvement in SARP discrimination accuracy with concordance index of 0.975 and 0.921 in the training and validation cohorts, respectively. Calibration curves and decision curve analysis confirmed the satisfactory clinical feasibility and utility of nomogram. The risk classification system displayed excellent performance on identifying SARP occurrence (P < .001).Conclusions: The delta-radiomics nomogram and risk classification system as low-cost and noninvasive means exhibited superior predictive accuracy and provided individualized probability of SARP stratification for patients with EC. [ABSTRACT FROM AUTHOR]- Published
- 2021
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33. Mechanistic insights into the leaching and environmental safety of arsenic in ceramsite prepared from fly ash.
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Song, Bing, Liu, Zequan, Li, Chengming, Zhou, Shiji, Yang, Linjun, Chen, Zhiliang, and Song, Min
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FLY ash , *ENVIRONMENTAL security , *ARSENIC , *INDUSTRIAL wastes , *FERRIC oxide , *BACTERIAL leaching - Abstract
Utilizing fly ash to prepare ceramsite is a promising way to immobilize heavy metals and recycle industrial solid waste. However, traditional preparation method of fly ash ceramsite has the disadvantages of large ignition loss. Therefore, the present study applied the pressure molding method to enhance solid content and improve the strength of ceramsite. The optimal preparation conditions of ceramsite were suggested as preheating at 450 °C for 25 min followed by sintering at 1050 °C for 30 min. Under such conditions, ceramsite with high compressive strength of 10.8 Mpa, bulk density of 878 kg m−3, and 1-h water absorption of 18.5% was fabricated, in compliance with Chinese standard (GB/T 1743.1–2010). The arsenic leaching concentration from the resulting product was considerably lower than Chinese standard (GB 5085.3–2007). Moreover, arsenic volatilization during ceramsite calcination was insignificant, and the vast majority of arsenic remained in resulting ceramsite. A geochemical speciation model developed for the multiple component system in ceramsite suggested that FeAsO 4 , Ca 5 (OH) (AsO 4) 3 , and hydrous ferric oxide adsorption are the primary mechanisms retaining arsenic in ceramsite. Additionally, based on density functional theory calculations and biotoxicity test, the binding site of arsenic atom on mineral components and the environmental safety of ceramsite was determined and evaluated. [Display omitted] • Geochemical speciation model of ceramsite was established for the first time. • The pressure molding method was applied to enhance the solid content of ceramsite. • The volatilization of heavy metal arsenic during ceramsite sintering was studied. [ABSTRACT FROM AUTHOR]
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- 2023
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34. C+ ion implanted single crystal diamond with amorphous surface for efficient oxygen evolution catalysis.
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Tu, Juping, Wang, Yong, He, Jian, Liu, Jinlong, Jia, Baorui, Chen, Liangxian, Wei, Junjun, and Li, Chengming
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SINGLE crystals , *DIAMOND surfaces , *HYDROGEN evolution reactions , *CARBON-based materials , *ION implantation , *DIAMOND films , *CATALYSIS , *DIAMOND crystals - Abstract
Oxygen evolution reaction (OER) is critical in water splitting for green hydrogen gas production due to its sluggish kinetics; however, commercial OER catalysts commonly suffer from high cost, low catalytic activity and poor stability. Herein, we developed a C+ ion implantation method to modify single crystal diamond, and the resultant surface amorphous layer not only raised the active site number but also increased the content of the C=O group, thus significantly improving the OER activity. The C+ ion implanted high-temperature and high-pressure (C+-HTHP) and chemical vapor deposition (C+-CVD) diamonds both exhibit low OER overpotential with η 10 of 317 mV and 325 mV respectively, superior to those of HTHP diamond (360 mV), CVD diamond (395 mV) and RuO 2 (364 mV). The potentiostatic testing shows that the C+ implanted diamonds almost didn't undergo the rise of OER overpotential upon catalysis for more than 12 h at a current density of 10 mA cm−2, suggesting a high catalytic stability, owing to the strong bonding between single crystal diamond and amorphous carbon layer. For the first time, we utilized carbon ion implantation to prepare diamond-based high-performance OER catalyst, which broadens the understanding of carbon-based materials in OER catalysis. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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- View/download PDF
35. Cardiac Substructures Dosimetric Predictors for Cardiac Toxicity After Definitive Radiotherapy in Esophageal Cancer.
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Cai, Guoxin, Li, Chuanbao, Li, Jisheng, Yang, Jianmin, Li, Chengming, Sun, Liangchao, Li, Jianing, Yu, Jinming, and Meng, Xue
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CARDIOTOXICITY , *ESOPHAGEAL cancer , *RECEIVER operating characteristic curves , *RADIATION dosimetry , *ACUTE coronary syndrome - Abstract
To investigate the predictive value of the cardiac substructures (CSs) dosimetric parameters for cardiac toxicity after definitive radiation therapy in locally advanced esophageal cancer. Between August 2010 and January 2016, 716 patients with stage 2-3 esophageal cancer receiving definitive radiation therapy at 2 institutions were divided into training (n = 432) and external validation (n = 284) cohorts. Dose-volume histogram parameters for the whole heart (WH) and CSs were extracted. Competing risks and Cox regressions analyses were performed. The predictive performance of the models was evaluated using the area under the receiver operating characteristic curve (AUC) and the Brier score. With a median follow-up of 93 months, 68 patients (15.7%) developed grade ≥3 cardiac events (G3+ CEs), with a median of 13.5 months to the first event. Multivariable analysis showed left ventricle, left anterior descending (LAD), and mean left circumflex (LCX) variables were significantly associated with G3+ CEs. The AUCs and Brier scores demonstrated favorable predictive accuracies of the models integrating these CS variables when predicting G3+ CEs in the training and validation cohorts. However, compared with the WH variables, the CS variables did not significantly improve the prediction of G3+ CEs. Nevertheless, when G3+ acute coronary syndrome and/or congestive heart failure (ACS/CHF) CE was the outcome of interest, models based on the LAD or LCX variables were superior to the WH variable models in training and validation cohorts. Models based on CS variables showed favorable predictive accuracy for G3+ CEs. The LAD and LCX variables significantly improved the prediction of G3+ ACS/CHF events compared with the WH variables. Radiation doses to CSs, such as LCX and LAD, should be monitored to help reduce the occurrence of significant CEs in patients with esophageal cancer undergoing definitive radiation therapy. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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36. Preparation strategy for low-stress and uniform SiC-on-diamond wafer: A silicon nitride dielectric layer.
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Zheng, Yuting, Zhang, Qinrui, Qiao, Guanzhong, Wei, Junjun, Liu, Jinlong, Chen, Liangxian, An, Kang, Zhang, Xiaotong, Ye, Haitao, Zhou, Haojun, Tao, Hongliang, Yin, Yuhang, Ouyang, Xiaoping, and Li, Chengming
- Subjects
- *
SILICON nitride , *DIAMOND crystals , *DIAMOND thin films , *SILICON wafers , *CHEMICAL vapor deposition , *DIAMOND films , *MICROWAVE plasmas , *ATOMS , *MAGNETRON sputtering - Abstract
Reducing the self-heating of SiC- and GaN/SiC-based high-powered devices by integrating diamond films offers promising performance enhancement of these devices. However, such a reduction strategy faces serious problems, such as diamond nucleation on SiC and stress accumulation greater than 10 GPa. In this work, a SiN x dielectric layer (∼50 nm) was coated onto the C polar face of a 4H–SiC wafer using microwave plasma chemical vapor deposition (MPCVD) to improve direct dense diamond nucleation and growth, significantly reduce the stress, and build Si–C(SiC)⋯Si⋯C(diamond) bond bridges. This SiN x thin layer, prepared by activating Si ions under Ar/N plasma during magnetron sputtering, gave rise to local Si 3 N 4 crystal features and a low effective work function (EWF) for promoting surface dipoles with electronegative carbon-containing groups. In the H plasma environment during diamond growth, the local Si 3 N 4 crystal was amorphized, and the N atoms escaped as a result of atomic H and the high temperature. At the same time, C atoms diffused into the SiN x and formed C–Si bonds (49.7% of the total C bonds) by replacing N–Si and Si–Si, thus increasing the direct nucleation density of the diamond grains. The diamond thin film grew rapidly and uniformly, with a grain size of approximately 2 μm in mixed orientation, and the stress of the 2-inch SiC-on-diamond wafer was extremely low (to ∼0.1–0.2 GPa). In comparison, partially connected diamond grains (>10 μm) on the bare SiC in the preferential (110) orientation resulted in a film with twin-grain features and significant stress, which was associated with the hexagonal lattice interface of 4H–SiC. These results are considered the material and surface/interface bases for actively controlling wafer fabrication and enhancing the heat dissipation of SiC and GaN/SiC electronics. [ABSTRACT FROM AUTHOR]
- Published
- 2022
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37. Early Mesozoic polyphase contractional deformation in the Yanshan belt: Implications for the destruction of the north China Craton.
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Huang, Yingzhu, Zhang, Changhou, Li, Chengming, and Teng, Fei
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MESOZOIC Era , *ROCK deformation , *IGNEOUS intrusions , *LITHOSPHERE , *GEOCHEMISTRY , *THRUST belts (Geology) - Abstract
[Display omitted] • The northern North China Craton was in a contractional setting in early Mesozoic. • Post-collisional contractional deformation was due to the lithosphere delamination. • A decoupling process dominated the early stage of the destruction of the NCC. After the collision of the Mongolian arc terranes with the amalgamated Bainaimiao arc and North China Craton in the latest Permian to earliest Triassic, the northern North China Craton ended the Andean-type accretionary orogenesis. The nature of the subsequent post-collision tectonic setting in early Mesozoic in the northern North China Craton remains controversial. Some workers proposed that the northern North China Craton evolved into a post-orogenic extensional stage. However, this view was mainly built on geochemistry studies of Triassic plutonic rocks in northern North China Craton while it had never received support from studies of tectonic deformation. In contrast, our recent field mapping combining with geochronological studies in the Yanshan belt suggest that the northern North China Craton was in an overall polyphase multi-directional contractional settings in early Mesozoic. We have identified four stages of contractional deformation (D 1 -D 4) in this region. D 1 (250–231 Ma) is the intracratonic response to the collision of the Mongolia arc terranes with the NCC. D 2 (214 ∼ 207 Ma) and D 3 (204 ∼ 195 Ma) are post-collisional intracratonic contractional deformation which occurred synchronously with the lithosphere thinning. D 2 and D 3 and the intervened plutonism might be a crustal response to the delamination and sinking of the over-thickened lithosphere of the northern North China Craton. D 4 is the result of the west-ward subduction of the Izanagi plate beneath the eastern Asian continent plate in the Early Jurassic. These findings together with previous studies indicate that the northern North China Craton experienced a long period of polyphase contractional deformation before its final destruction in the Early Cretaceous. The early stage of the destruction of the North China Craton is characterized by coeval lithosphere thinning and crustal thickening. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
38. Evaluation of the fracture strength of ultra-thick diamond plate by the three-point bending ISO standard method.
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An, Kang, Li, Shiyu, Shao, Siwu, Liu, Peng, Liu, Jinlong, Chen, Liangxian, Wei, Junjun, Zheng, Yuting, Liu, Qing, and Li, Chengming
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- *
CHEMICAL vapor deposition , *DIAMONDS , *DIAMOND films , *PLASMA jets , *PLASMA arcs , *SAPPHIRES , *FRACTURE strength - Abstract
In this study, standard diamond bars were prepared using an ultra-thick diamond plate, and the bars had sizes consistent with the International Organization for Standardization (ISO) 14704:2016(E) three-point bending method for measuring the fracture strength. Ultra-thick diamond plate with dimensions of 125 mm (diameter) × 6.5 mm (thickness) were deposited using direct current arc plasma jet chemical vapour deposition. After cutting, grinding, and polishing, 12 diamond bars meeting the requirements of the ISO standard were prepared (36 mm × 4 mm × 3 mm) and tested for fracture strength using the cited ISO standard and elastic modulus using deflection measurements. The fracture strength of the ultra-thick diamond plate was found to be 580 ± 66 MPa. In addition, for comparison, the fracture strengths of standard ZnS, sapphire, and alumina were also analysed. Crucially, this is the first report of the fracture strength of standard-sized diamond plate. The effects of the defects and grain size on the crack formation and failure of the diamond film were analysed. The diamond's fracture strength was affected by the sample thickness, which caused the gradual accumulation of defects as this dimension increased, but not by its length and width. The elastic moduli of sapphire and alumina were compared. Overall, the measurement of the fracture strengths of ultra-thick diamond plate via the ISO standard is important for industrial applications. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
39. Antibacterial properties of polycrystalline diamond films.
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Cumont, Aude, Zhang, Ruoying, Zheng, Yuting, Corscadden, Louise, Oggioni, Marco R., Li, Chengming, Liu, Ran, and Ye, Haitao
- Subjects
- *
DIAMOND films , *CHEMICAL vapor deposition , *RAMAN spectroscopy , *SILICON wafers , *AMORPHOUS carbon , *DIAMONDS , *DIAMOND crystals , *MICROCOCCACEAE - Abstract
Electronic and mechanical properties, and their biocompatibility, make diamond-based materials promising biomedical applications. The cost required to produce high quality single crystalline diamond films is still a hurdle to prevent them from commercial applications, but the emergence of polycrystalline diamond (PCD) films grown by chemical vapour deposition (CVD) method has provided an affordable strategy. PCD films grown on silicon wafer have been used throughout and were fully characterised by SEM, XPS, Raman spectroscopy and FTIR. The samples contain nearly pure carbon, with impurities originated from the CVD growth and the silicon etching process. Raman spectroscopy revealed it contained tetrahedral amorphous carbon with small tensile stress. The sp2 carbon content, comprised between 16.1 and 18.8%, is attributed to the diamond grain boundaries and iron-catalysed graphitisation. Antibacterial properties of PCD films were performed with two model bacteria, i.e. Escherichia coli (Gram-negative) and Staphylococcus aureus (Gram-positive) using direct contact and shaking flask methods. The samples showed strong bacteriostatic properties against S. aureus and E. coli with the direct contact method and no influence on planktonic bacterial growth. These results suggest that the bacteriostatic mechanism of PCD films is linked to their surface functional groups (carbon radicals and –NH 2 and –COOH groups) and that no diffusible molecules or components were involved. [ABSTRACT FROM AUTHOR]
- Published
- 2021
- Full Text
- View/download PDF
40. RelJoin: Relative-cost-based selection of distributed join methods for query plan optimization.
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Liang, Feng, Lau, Francis C.M., Cui, Heming, Li, Yupeng, Lin, Bing, Li, Chengming, and Hu, Xiping
- Subjects
- *
DISTRIBUTED databases , *DISTRIBUTED computing , *TELECOMMUNICATION systems , *COMMUNICATION patterns , *COMMUNICATION models , *DATA transmission systems - Abstract
Selecting appropriate distributed join methods for logical join operations in a query plan is crucial for the performance of data-intensive scalable computing (DISC). Different network communication patterns in the data exchange phase generate varying network communication workloads and significantly affect the distributed join performance. However, most cost-based query optimizers focus on the local computing cost and do not precisely model the network communication cost. We propose a cost model for various distributed join methods to optimize join queries in DISC platforms. Our method precisely measures the network and local computing workloads in different execution phases, using information on the size and cardinality statistics of datasets and cluster join parallelism. Our cost model reveals the importance of the relative size of the joining datasets. We implement an efficient distributed join selection strategy, known as RelJoin in SparkSQL, which is an industry-prevalent distributed data processing framework. RelJoin uses runtime adaptive statistics for accurate cost estimation and selects optimal distributed join methods for logical joins to optimize the physical query plan. The evaluation results on the TPC-DS benchmark show that RelJoin performs best in 62 of the 97 queries and can reduce the average query time by 21% compared with other strategies.1 [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
41. Authentication of chicken-derived components in collagen-containing foods using natural macromolecular marker fragments by LC-MS method.
- Author
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Deng, Guiya, Jiang, Xianchao, Song, Zihao, Li, Chengming, Guan, Yuepeng, Guo, Shangwei, and Huang, Yaqin
- Subjects
- *
FAT substitutes , *BIOPOLYMERS , *DETECTION limit , *FOOD quality , *FOOD safety , *COLLAGEN - Abstract
Collagen is a biopolymer in animals that has been widely used in the food field to improve the value of health benefits in products. Chicken skin, which is a collagen-containing food, is popular as a healthy fat replacer for processed meat. To enable high information transparency of the products, the chicken-derived components need to be traceable to guarantee food safety and quality. However, the current methods for identifying the chicken-derived components in food still lack accuracy. Here a combination of two marker peptides were discovered and employed to establish a sensitive method based on LC-MS for the detection of chicken-derived components in collagen-containing foods. This method has a very low detection limit of 0.33 pg and 0.16 pg for two marker peptides, respectively. The results illustrated that the combination of these maker peptides could be utilized for the authentication of the chicken skin-derived components in processed meat. [Display omitted] • Two marker peptides have been identified from chicken skin collagen. • Chicken skin collagen can be sensitively detected by the peptides at low limit of detection. • Chicken skin adulterated in minced meat can be detected accurately. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
42. Surface termination of the diamond microchannel and single-phase heat transfer performance.
- Author
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Tu, Junlei, Shi, Jiadong, Chen, Liangxian, Liu, Jinlong, Li, Chengming, and Wei, Junjun
- Subjects
- *
DIAMOND surfaces , *HEAT transfer , *HEAT transfer coefficient , *X-ray photoelectron spectroscopy , *LASER beam cutting - Abstract
• Large scale all diamond microchannel has been fabricated by DC arc jet CVD and laser cutting. • Three methods have been carried out to modify the diamond microchannel surface to fulfill different terminations, including oxygen termination, hydrogen termination and fluorine termination. • The change of the surface properties of the diamond surface referring to the real situation flow was analyzed and explained in detail. The diamond microchannel heat sink (D-MCHS) has extremely ultra-high stability and heat transfer capacity, and the surface modification can further improve the heat dissipation capacity of D -MCHS. In this study, diamond microchannels were modified by three surface termination operations, including oxygen-terminated (OT), hydrogen (HT), and fluorine-terminated surfaces (FT). Referring to the real situation, after the treatment of heat flow, the hydrophobic properties of HT-diamond microchannels decreased and resulted in the increase of surface heat transfer coefficient by 11%. The hydrophilic properties of OT-diamond tend to be stable after being significantly reduced, and the heat transfer coefficient decreased by 7%. FT-diamond was the most stable; its hydrophobicity remained constant after a slight decrease in the initial stage, and the corresponding surface heat transfer coefficient increased by 14%. X-ray photoelectron spectroscopy (XPS) was used to evaluate the surface bonding state of different terminal treatments. The results show that although the F terminal has more stable hydrophobicity, its surface temperature is 5 °C higher than that of the hydrophilic terminal, and the heat transfer coefficient is reduced from 9500 to 6000 W/(m2K), decreasing by nearly 58%. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
43. Enhanced arsenic removal by reusable hexagonal CeO2/Fe2O3 nanosheets with exposed (0001) facet.
- Author
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Song, Bing, Zhi, Zejian, Zhou, Qiang, Wu, Di, Yu, Lei, Gong, Feng, Yin, Ying, Meng, Fanyue, Li, Chengming, Chen, Zhiliang, and Song, Min
- Published
- 2022
- Full Text
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44. Microstructure and properties of La-doped Er2O3 anti-reflection films on CVD diamond.
- Author
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Huang, Yabo, Zhu, Xiaohua, Cao, Shuqin, Chen, Liangxian, Shao, Siwu, An, Kang, Zheng, Yuting, Liu, Jinlong, Wei, Junjun, and Li, Chengming
- Subjects
- *
ANTIREFLECTIVE coatings , *MAGNETRON sputtering , *DIAMOND crystals , *DIAMOND films , *CRYSTAL grain boundaries , *CHEMICAL vapor deposition , *X-ray photoelectron spectroscopy - Abstract
[Display omitted] • The La-doped Er 2 O 3 anti-reflection films was prepared by the power of magnetron sputtering. • The compound of La 2 O 3 formed along the grain boundary of the columnar crystal structure of the polycrystalline film. • The highest hardness and yield strength of the La-doped Er 2 O 3 film was two times higher than that of pure Er 2 O 3 film. • The transmittance of the La-doped Er 2 O 3 anti-reflection films only decreased 1% after erosion. The composition and microstructure consisting of anti-reflection films was obtained by the power of magnetron sputtering. X-ray photoelectron spectroscopy (XPS) and High-resolution transmission electron microscopy (HRTEM) provided evidence to support that the doping La element exists as oxide in the grain boundaries of the matrix Er 2 O 3 films. The undoped and La-doped Er 2 O 3 films show a columnar crystal structure of the main cubic (2 2 2) plane. Twinning and a large number of dislocations show up in the undoped Er 2 O 3 films due to the competitive growth of the columnar crystal. In addition, the La-doped Er 2 O 3 films show a lower roughness (RMS) value in comparison with undoped Er 2 O 3 films. The grain size of columnar crystals decreases significantly with increasing La concentration in the La-doped Er 2 O 3 films. The fine grains resulted in the La-doped Er 2 O 3 films developing high mechanical and impact resistance properties, with an increase in hardness from 12.6 ± 2.1 GPa to 26.1 ± 3.4 GPa and the eroding area rate decreasing from 38.9 % to 1.9 %. Moreover, the La-doped Er 2 O 3 anti-reflection films on the chemical vapor deposition (CVD) diamond substrate maintained 74 % transmittance in the long-wavelength infrared range of 8–12 μm after sand eroding. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
45. Nitrobenzoxadiazole based lipid droplets specific probes for atherosclerosis imaging.
- Author
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Zhuang, Weihua, Chen, Zhiqian, Liu, Qi, Li, Chengming, Ma, Di, Chen, Jingruo, Zhou, Linsen, Li, Shufen, and Chen, Mao
- Subjects
- *
ATHEROSCLEROSIS , *CELL imaging , *AQUEOUS solutions , *FLUORESCENCE - Abstract
Fluorescence probes have shown great potential in lipid droplets (LDs) imaging, whereas the imaging performance of the present commercial dyes is far from ideal. In addition, there still is lack of an effective strategy for designing LDs specific probes with satisfactory imaging performance. In this work, we have provided a novel method and probes based on donor (D)-acceptor (A) structure with nitrobenzoxadiazole (NBD) as the A unit and benzene derivatives as the D units, which are expected to show strong emission in lipid environment. Four probes (N–B , N–MeB , N–MeOB and N–Me 2 NB) with increasing electron-donating ability were prepared, whose fluorescence-emission changed from aggregation-induced emission (AIE) (N–B and N–MeB) to aggregation-caused quenching (ACQ) (N–MeOB and N–Me 2 NB). Intriguingly, the emission of these probes in oil changed from blue region to red (652 nm) with the increase of electron-donating ability from N–B to N–Me 2 NB , indicating the great emission regulable ability of this strategy. Moreover, these probes could specifically stain the intracellular and tissular LDs, which had shown considerable performance in the studying of LDs spatial distributions in mice and human atherosclerosis plaques. Impressively, N–Me 2 NB with the strongest electron-donating group of N-dimethylaniline showed negligible emission in aqueous solution but remarkable enhanced emission in oil, which could still efficiently stain the intracellular LDs at 200 nM. This novel construction strategy would provide new ideas for preparation of LDs specific probes. • A novel strategy for designing lipid droplets (LDs) specific probe was provided. • The fluorescence emission of N–MeOB and N–Me 2 NB were significantly enhanced in lipid environment. • N–MeOB and N–Me 2 NB showed great LDs imaging performance in cells. • N–MeOB and N–Me 2 NB can detect the LDs distribution in mice and human atherosclerosis plaques. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
46. C-Si interface on SiO2/(1 1 1) diamond p-MOSFETs with high mobility and excellent normally-off operation.
- Author
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Zhu, Xiaohua, Bi, Te, Yuan, Xiaolu, Chang, Yuhao, Zhang, Runming, Fu, Yu, Tu, Juping, Huang, Yabo, Liu, Jinlong, Li, Chengming, and Kawarada, Hiroshi
- Subjects
- *
METAL oxide semiconductor field-effect transistors , *FIELD-effect transistors , *METAL oxide semiconductor field , *HOLE mobility , *X-ray photoelectron spectroscopy , *DIAMONDS - Abstract
[Display omitted] • A high channel hole mobility of 200 cm2V−1s−1 was achieved in C-Si interface (1 1 1) diamond MOSFETs. • The C-Si interface provides the MOSFETs with an excellent normally-off operation. • The advantage of boron doping in (1 1 1) diamond provides a large maximum current density. • The anatomically flat and strain-free interface between the (1 1 1) diamond and SiO 2 film was confirmed by HRTEM. • The existence of C-Si bonds at the interface was proved by EELS and XPS. In this paper, a diamond-silicon (C-Si) interface was constructed on a (1 1 1) diamond substrate by annealing the SiO 2 gate insulator in a reductive atmosphere. Corresponding metal-oxide-semiconductor field effect transistors (MOSFETs) with a C-Si conductive channel were fabricated. The MOSFETs demonstrate excellent normally-off operation with a high threshold voltage (V th) of −16 V and a high current density of −167 mA/mm, with a gate length (L G) of 4 μm. The channel hole mobility (μ FE) reaches 200 cm2V−1s−1 with a L G of 10 μm, and the interface state density (D it) is as low as 3.8 × 1011 cm−2 eV−1. The high-resolution transmission electron microscopy (HRTEM) image displays a coherent and strain-free interface between the SiO 2 film and (1 1 1) diamond, which ensures a high μ FE and low D it in the MOSFETs. The interface is dominated by C-Si bonds, which are confirmed by atomic-scale electron energy loss (EELS) quantification, spectroscopic characterization, and X-ray photoelectron spectroscopy (XPS). These results demonstrate that diamond, directly combined with SiO 2 , is ideal for implementation in power devices. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
47. Surface etching evolution of mechanically polished single crystal diamond with subsurface cleavage in microwave hydrogen plasma: Topography, state and electrical properties.
- Author
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Zheng, Yuting, Jia, Yanwei, Liu, Jinlong, Wei, Junjun, Chen, Liangxian, An, Kang, Yan, Xiongbo, Zhang, Xiaotong, Ye, Haitao, Ouyang, Xiaoping, and Li, Chengming
- Subjects
- *
HYDROGEN plasmas , *MICROWAVE plasmas , *DIAMOND crystals , *SINGLE crystals , *DIAMOND surfaces , *GRINDING & polishing , *DIAMONDS , *DIAMOND films - Abstract
Surface etching of single-crystal diamond (SCD) in hydrogen plasma plays a decisive role for high-quality homoepitaxy and surface conduction of diamond. The complexity of surface/subsurface condition such as defects would give rise to the distinct morphology features and even further result in the unpredictable properties. Correspondingly, the evolutionary relationship between the morphology and electrical properties of mechanically polished SCDs which have typical cleavage damage in microns depth after hydrogen plasma treatment still needs to be further completed. In this work, the chemical vapor deposited (CVD) SCDs with uniform polishing-caused subsurface cleavage were immersed in microwave hydrogen plasma for variable duration. Time-dependent morphological evolution, multi-mode etched pits (EPs) (resulting from local defects/cracks and dislocations) and associated etching mechanism were comprehensively studied. At the early stage of plasma treatment before 60 min, owing to the obvious surface roughing generated by preferential etching (with the rate of >400 nm/h) of severe mechanically damaged regions, the hole mobility was significantly deteriorated, also accompanying with the apparent drop of sheet concentration. Concurrently, the deposited surface sp 2 amorphous carbon (a -C) nanodots on diamond surface and non- sp 3 hydrogen bonds reconstruction, which arising from defect-etching produced local abundant carbon-containing radicals or possible exfoliation generated by hydrogen penetration of massive defective regions, also would play an adverse role for the conduction associated with (100) C–H surface. However, the surface roughness was reduced from the maximum 13.2 nm–4.2 nm by prolonging etching, resulting from the smoothing effect of small-angle crystal misorientation on waved height difference related to the uniform (111) cleavage and the removal of dense irregular EPs associated with polishing-induced local defects as well as the vanishing of surface a -C nanodots. In this case, the improvement of surface electrical properties together with the negative correlation of the mobility and sheet concentration were appeared by the gradual formation of (100) diamond surface and the building of uniform (100) C–H bonds. • CVD SCDs with typical subsurface damages(defects) were treated in pure hydrogen plasma. • Morphology evolution associated with polishing defects was time-dependently presented. • Surface sp2 nanodots deposition from defect-etching and CH reconstruction would affect electrical properties. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
48. China's transportation sector carbon dioxide emissions efficiency and its influencing factors based on the EBM DEA model with undesirable outputs and spatial Durbin model.
- Author
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Zhao, Pengjun, Zeng, Liangen, Li, Peilin, Lu, Haiyan, Hu, Haoyu, Li, Chengming, Zheng, Mengyuan, Li, Haitao, Yu, Zhao, Yuan, Dandan, Xie, Jinxin, Huang, Qi, and Qi, Yuting
- Subjects
- *
CARBON emissions , *URBAN density , *DATA envelopment analysis , *CLIMATE change , *SUSTAINABLE transportation - Abstract
The threat of global climate change has caused the international community to pay close attention to atmospheric levels of greenhouse gases such as carbon dioxide. Transportation sector carbon dioxide emissions efficiency (TSCDEE) is a key indicator used to prioritize sustainable development in the transportation sector. In this paper, the epsilon-based measure data envelopment analysis model with undesirable outputs is applied to estimate TSCDEE for 30 provinces in China from 2010 to 2016. We also analyze influencing factors using the spatial Durbin model. Research shows that the overall TSCDEE of the Chinese provinces studied was 0.618, indicating that most regions are still in need of improvements. The provinces with the highest TSCDEE are located in developed coastal regions of China. This study shows that factors such as transportation structure, traffic infrastructure level, and technological progress have prominent positive effects on TSCDEE, while both urbanization level and urban population density exert significantly negative effects on TSCDEE. The findings should have a far-reaching impact on the sustainable development of global transportation. [Display omitted] • Providing more accurate method in estimating CO 2 emissions of the transport sector. • Focusing on the transportation sector carbon dioxide emissions efficiency (TSCDEE). • Technological progress is the key to improve TSCDEE among different factors in China. • Higher mode share of water and rail transport contributes to higher TSCDEE in China. • Urbanization presents significantly negative effect on TSCDEE in China. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
49. Impact of deposition temperature on microstructure and properties of erbium oxide antireflective films deposited on CVD diamond substrates.
- Author
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Huang, Yabo, Chen, Liangxian, Shao, Siwu, Zhu, Xiaohua, Huang, Ke, An, Kang, Zheng, Yuting, Liu, Jinlong, Wei, Junjun, and Li, Chengming
- Subjects
- *
OXIDE coating , *ERBIUM , *CHEMICAL vapor deposition , *CHEMICAL bonds , *DIAMOND films , *MICROSTRUCTURE - Abstract
To improve the transmittance of chemical vapor deposition (CVD) diamond, erbium(III) oxide (Er 2 O 3) antireflective films were deposited on CVD diamond substrates by radio frequency (RF) magnetron sputtering. Effects of deposition temperature on structure, chemical composition and properties of the samples were investigated. A strong correlation was observed between the deposition temperature and crystalline structure evolution of the Er 2 O 3 antireflective films. With rising deposition temperature, the deposition rate, grain size and surface roughness of the Er 2 O 3 antireflective films increased. Changes of composition and chemical bonding of the films were analyzed. Results showed that the amount of bonding between Er and O atoms surface as the temperature increased. The films were structured by amorphous, monoclinic and cubic phase, with preferential orientations of C-Er 2 O 3 {222} at deposition temperature increased to 400 °C. A thickness of 10 nm transition layer was observed between the Er 2 O 3 antireflective films and the CVD diamond substrates by transmission electron microscopy (TEM). Moreover, the transition layer feature primarily consisted of Er, O and C. The hardness and modulus of Er 2 O 3 antireflective films were increased for higher deposition temperature, which positively affects the IR transmittance and adhesion strength of the Er 2 O 3 antireflective films on CVD diamond substrates. • The maximum transmittance of Er 2 O 3 /diamond sample was 80% in 7–11 μm range. • Texturization of Er 2 O 3 film interface was studied by HRTEM. • The higher deposition temperature favors crystallization of Er 2 O 3 film. • This study meets the requirements of windows for infrared (IR) imaging systems coating in the LWIR range. [ABSTRACT FROM AUTHOR]
- Published
- 2021
- Full Text
- View/download PDF
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