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36 results on '"Qian, Yuhao"'

11. Research on the Promotion Path of Collaborative Emergency Response Capability of Smoke-Free Cities in the Digital Age

Author

Qian Yuhao, Chen Junshi, Wang Chen, and Liu Chen

Subjects
Health (social science), Health Policy, Public Health, Environmental and Occupational Health
Abstract

In recent years, major public safety incidents occur frequently in smoke-free cities. Under the complex and severe situation, the emergency preparedness capacity of smoke-free cities in China needs to be improved. In this paper, 50 fire emergency plans in smoke-free City F are taken as samples, and the qualitative comparative analysis method of clear set (csqca) is applied to explore the improvement path of emergency preparedness ability. Three influence paths are obtained to improve the emergency preparedness ability, which are information resource integration mode, business collaboration pre control mode and system route mode. The results provide reference for improving the effectiveness of pre disaster prevention, enhance the emergency preparedness capacity of smoke-free cities and improving the effect of emergency management.

Published
2021

14. Microfiber-based polarization beam splitter and its application for passively mode-locked all-fiber laser

Author

Mengmeng Chen, Zhou Xiabing, Lin Zhang, Mingwei Qiu, Qian Yuhao, and Zuxing Zhang

Subjects
Materials science, Fabrication, business.product_category, Extinction ratio, business.industry, Bandwidth (signal processing), Physics::Optics, Polarization (waves), Laser, Atomic and Molecular Physics, and Optics, law.invention, Wavelength, law, Fiber laser, Microfiber, Optoelectronics, Electrical and Electronic Engineering, business
Abstract

Nonlinear polarization evolution based on polarization beam splitter (PBS) is a classical technique for passive mode-locking of fiber lasers. Different from commonly used bulky PBS, in this paper all-fiber PBSs composed of two parallel coupled microfibers have been proposed and fabricated under the condition of appropriate microfiber diameter and coupling length. Using our fabricated microfiber PBSs, passively mode-locked all-fiber lasers have also been demonstrated. The results indicate that the microfiber-based PBS has advantages of simple fabrication, compact size, and most importantly, variable polarization extinction ratio and operation bandwidth. The all-fiber mode-locked lasers with the microfiber PBSs generating stable pulses at both 1.0 μm and 1.5 μm wavelength bands have comparable performance with their counterparts based on bulky PBSs. It may be a step towards true all-fiber mode-locked laser and other all-fiber systems.

Published
2021

20. A novel microfiber refractometric sensor fabricated with tapering-twisting-tapering technique

Author

Xiaoying Fang, Zuxing Zhang, Yu Cai, Qian Yuhao, and Bing Sun

Subjects
business.product_category, Materials science, Fabrication, business.industry, Ranging, Tapering, 02 engineering and technology, Intensity (physics), 020210 optoelectronics & photonics, Interference (communication), Microfiber, 0202 electrical engineering, electronic engineering, information engineering, Optoelectronics, business, Refractive index
Abstract

In this paper, a novel microfiber refractive index sensor prepared with tapering-twisting-tapering technique has been proposed and demonstrated for the first time. Experimental results show that the interference intensity of the novel microfiber increases with the increment of pre-tapered length and the intervening twist number. Furthermore, the refractive index sensitivity of this microfiber sensor can reach to ∼809 nm/refractive index unit (RIU) in the refractive index ranging from 1.30 to 1.33. Taking advantages of its tiny size, easy preparation and flexible design, the novel microfiber has great potential application in refractive index sensing.

Published
2017

21. Novel temperature-independent microfiber sensor fabricated with the tapering-twisting-tapering technique

Author

Zuxing Zhang, Qian Yuhao, Hongdan Wan, and Bing Sun

Subjects
Materials science, business.product_category, business.industry, Tapering, 01 natural sciences, Atomic and Molecular Physics, and Optics, Intensity (physics), 010309 optics, Optics, Fiber Bragg grating, Interference (communication), 0103 physical sciences, Microfiber, Sensitivity (control systems), Electrical and Electronic Engineering, business, Engineering (miscellaneous), Refractive index, Photonic-crystal fiber
Abstract

In this paper, a novel twist and refractive index microfiber sensor fabricated with the tapering-twisting-tapering technique has been proposed and demonstrated, for the first time to the best of our knowledge. Experimental results show that the interference intensity of the microfiber increases with the increment of pre-tapered length and the intervening twist number. The sensitivity of the microfiber sensor with respect to twist is found to be 2.817 dB/(rad/m) and the refractive index sensitivity of this microfiber sensor can reach to ∼809 nm/refractive index unit in the refractive index ranging from 1.30 to 1.33. Moreover, considering that its temperature sensitivity is 0.005 dB/°C, it will not suffer from the cross sensitivity to temperature.

Published
2019

29. Multiwavelength Mode-Locked Fiber Laser Based on Micro-Fiber Loop

Author

蔡宇 Cai Yu, 万洪丹 Wan Hongdan, 张祖兴 Zhang Zuxing, 张琳 Zhang Lin, and 钱禹豪 Qian Yuhao

Subjects
Loop (topology), Mode locked fiber laser, business.product_category, Materials science, business.industry, Fiber laser, Microfiber, Optoelectronics, Electrical and Electronic Engineering, business, Atomic and Molecular Physics, and Optics, Electronic, Optical and Magnetic Materials
Published
2017

32. Reduction of NO with NH3over ferric oxide nanocrystals: the crystallographic facet-induced catalytic enhancementElectronic supplementary information (ESI) available. See DOI: 10.1039/c8cy01302k

Author

Huang, Zhiwei, Du, Yueyao, Zhang, Jie, Wu, Xiaomin, Shen, Huazhen, Qian, Yuhao, and Jing, Guohua

Abstract

Different synthesis methods of a given material will lead to different mesoscopic architectures, which in turn would strongly influence the catalytic performance. Therefore, morphology control is thought to be helpful for creating high-performance catalysts. Here, a series of well-defined α-Fe2O3crystals with different morphologies, including hexagon, rod, and diamond, have been prepared and investigated for the selective catalytic reduction (SCR) of NO with NH3, which is of major environmental interest for air pollution control. We report that the {001} surface of the hexagon-shaped Fe2O3catalyst is very active for NO removal. From temperature-programmed desorption measurements, we find that the NH3reactant adsorbed strongly on the {001} surface. In contrast, other high-index ferric oxide facets, including {012}, {−210}, {01−4}, {110}, and {1−10}, exhibit the weakly adsorbed state of NH3. Density functional theory calculations show that the {001} surface has a high surface energy of 1.4 J m−2, which should account for the observed SCR kinetics. A link between the experimentally observed activity trend and the exposed facets of ferric oxides has been established.

Published
2018
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34. Estrogen deficiency induces bone loss by increasing T cell proliferation and lifespan through IFN-γ-induced class II transactivator.

Author

Cenci, Simone, Toraldo, Gianluca, Weitzmann, M. Neale, Roggia, Cristiana, Gao, Yuhao, Wei Ping Qian, Yuhao, Sierra, Oscar, and Pacifici, Roberto

Subjects
OSTEOPOROSIS, CELL proliferation, T cells, ESTROGEN, TUMOR necrosis factors
Abstract

Expansion of the pool of tumor necrosis factor (TNF)-α-producing T cells is instrumental for the bone loss induced by estrogen deficiency, but the responsible mechanism is unknown. Here we show that ovariectomy up-regulates IFN-γ-induced class II transactivator, a multitarget immune modulator, resulting in increased antigen presentation by macrophages, enhanced T cell activation, and prolonged lifespan of active T cells. Up-regulation of class II transactivator derives from increased production of IFN-γ by T helper I cells, resulting from enhanced secretion of IL-12 and IL-18 by macrophages. The resulting T cell expansion and bone loss are prevented in vivo by both blockade of antigen presenting cell-induced T cell activation, and silencing of IFN-γ receptor signaling. Thus, increased IFN-γ-induced class II transactivator expression and the resulting enhanced T cell proliferation and lifespan are critical to the bone wasting effect of estrogen deficiency. [ABSTRACT FROM AUTHOR]

Published
2003
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35. An efficient absorbent of amine-based amino acid-functionalized ionic liquids for CO2 capture: High capacity and regeneration ability.

Author

Lv, Bihong, Jing, Guohua, Qian, Yuhao, and Zhou, Zuoming

Subjects
*IONIC liquids, *AMINO acids, *MOLECULAR weights, *NUCLEAR magnetic resonance, *REACTION mechanisms (Chemistry)
Abstract

An efficient and high capacity absorbent of amine-based amino acid-functionalized ionic liquid (IL) ([APmim][Gly]) was designed and prepared for CO 2 capture in this work. The achieved capacity of [APmim][Gly] was 1.23 mol CO 2 /mol IL (4.31 mol CO 2 /kg IL), which was much higher than that of the most existing dual functionalized ILs due to its low molecular weight. The largest weight loss temperature of [APmim][Gly] was found to be 370 °C, at that point, the weight loss was nearly 60% of its initial weight. Besides, [APmim][Gly] also owned a high regeneration ability even after multiple regenerations. In order to clarify the reaction mechanism of CO 2 absorption into [APmim][Gly] solution, 13 C nuclear magnetic resonance (NMR) was carried out to analyze the species of [APmim][Gly] solution at different CO 2 loadings. Different from the most reported mechanisms for CO 2 capture into functionalized ILs, the reaction between [APmim][Gly] and CO 2 was influenced by CO 2 loadings. The reaction could divide into two stages. It was started with the reversible chemical reaction to form carbamate, and followed by the CO 2 hydration reaction. At high CO 2 loading, the production of carbamate was easy to be decomposed. [ABSTRACT FROM AUTHOR]

Published
2016
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36. Facile synthesis of β-trifluoromethyl thioethers via DBN-catalyzed hydrothiolation of a-trifluoromethyl styrenes with thiols.

Author

Deng Y, Huang J, Qian Y, Sun Z, Huang Q, and Cao S

Abstract

A very simple and atom-economical method for the synthesis of vicinal trifluoromethyl thioethers via DBN-catalyzed hydrothiolation of α-trifluoromethyl styrenes with thiols was reported. The reaction proceeded smoothly under mild reaction conditions and provided the β-CF3-thioethers in moderate to good yields in an anti-Markovnikov manner., (© 2024 Wiley‐VCH GmbH.)

Published
2024
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