| 1. |
- Liu, Lindong, et al.
(författare)
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Intelligent simulation experimental study on influence of air velocity of air supply hood and exhaust hood with vertical push-pull ventilation
- 2019
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Ingår i: Journal of Intelligent & Fuzzy Systems. - : IOS PRESS. - 1064-1246 .- 1875-8967. ; 37:4, s. 4819-4826
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Tidskriftsartikel (refereegranskat)abstract
- The occupational health and safety problems caused by indoor dust and toxic gases in industrial plants are becoming increasingly serious. Vertical push-pull ventilation can effectively control dust and toxic gases and avoid indoor environmental pollution. The velocity of the air supply hood and exhaust hood in the push-pull ventilation intelligent device directly affects the control effect of the dust and toxic gases. However, no scholar has given a reasonable ratio of the air supply and exhaust velocity of the vertical push-pull ventilation device. Therefore, this paper uses the combination of Fluent numerical simulation technology and smoke visualization experiment to explore the best ratio of the air supply and exhaust velocity in the push-pull ventilation flow field. The research shows that the traces of the wind flow obtained by numerical analysis under different k which is the ratio of the air supply and exhaust velocity is consistent with the traces of visualized smoke in the actual experiment; The optimal ratio of air supply and exhaust is k = 1.75, which can effectively guarantee the indoor environment, occupational health and work efficiency of the operators.
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| 2. |
- Sui, Dong, et al.
(författare)
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Recent progress of cathode materials for aqueous zinc-ion capacitors: Carbon-based materials and beyond
- 2021
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Ingår i: Carbon. - : Elsevier BV. - 0008-6223. ; 185, s. 126-151
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Forskningsöversikt (refereegranskat)abstract
- As an emerging multivalent-ion-based energy storage device, aqueous zinc-ion capacitors (AZICs) combine the merits of zinc-ion batteries with high energy density, excellent safety, low cost and environmental friendliness, and the advantages of supercapacitors with high power density and superior cycling performance. Therefore, AZICs have been considered as a new promising electrochemical energy storage system. Though great progress of AZICs has been made recently, they are still in the infant stage and face many challenges. Specially, the unsatisfactory energy density needs to be improved to realize their practical applications, which calls for high-capacity cathode materials. In this review, after a brief introduction of progress and mechanism for AZICs, we provide a systematical overview of the latest advances in the state-of-art cathode materials. The synthesis route, structure and morphology, electrochemical performance, energy storage mechanism as well as the merits and drawbacks of various cathode materials are comprehensively compared and discussed. Finally, a summary and outlook of the challenges and future perspectives of AZICs were presented. With these, this review might offer some guidance for the future design of dedicated novel cathode materials to realize the great potential of AZICs.
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| 3. |
- Yang, Fengmei, et al.
(författare)
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Multi-Proxy Temperature Reconstruction from the West Qinling Mountains, China, for the Past 500 Years
- 2013
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Ingår i: PLOS ONE. - : Public Library of Science (PLoS). - 1932-6203. ; 8:2, s. e57638-
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Tidskriftsartikel (refereegranskat)abstract
- A total of 290 tree-ring samples, collected from six sites in the West Qinling Mountains of China, were used to develop six new standard tree-ring chronologies. In addition, 73 proxy records were assembled in collaboration with Chinese and international scholars, from 27 publically available proxy records and 40 tree-ring chronologies that are not available in public datasets. These records were used to reconstruct annual mean temperature variability in the West Qinling Mountains over the past 500 years (AD 1500–1995), using a modified point-by-point regression (hybrid PPR) method. The results demonstrate that the hybrid PPR method successfully integrates the temperature signals from different types of proxies, and that the method preserves a high degree of low-frequency variability. The reconstruction shows greater temperature variability in the West Qinling Mountains than has been found in previous studies. Our temperature reconstruction for this region shows: 1) five distinct cold periods, at approximately AD 1520–1535, AD 1560–1575, AD 1610–1620, AD 1850–1875 and AD 1965–1985, and four warm periods, at approximately AD 1645–1660, AD 1705–1725, AD 1785–1795 and AD 1920–1945; 2) that in this region, the 20th century was not the warmest period of the past 500 years; and 3) that a dominant and persistent oscillation of ca. 64 years is significantly identified in the 1640–1790 period.
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| 4. |
- Zhao, Yunlong, et al.
(författare)
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Stable Alkali Metal Ion Intercalation Compounds as Optimized Metal Oxide Nanowire Cathodes for Lithium Batteries
- 2015
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Ingår i: Nano letters (Print). - : American Chemical Society (ACS). - 1530-6984 .- 1530-6992. ; 15:3, s. 2180-2185
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Tidskriftsartikel (refereegranskat)abstract
- Intercalation of ions in electrode materials has been explored to improve the rate capability in lithium batteries and supercapacitors, due to the enhanced diffusion of Li+ or electrolyte cations. Here, we describe a synergistic effect between crystal structure and intercalated ion by experimental characterization and ab initio calculations, based on more than 20 nanomaterials: five typical cathode materials together with their alkali metal ion intercalation compounds A-M-O (A = Li, Na, K, Rb; M = V, Mo, Co, Mn, Fe-P). Our focus on nanowires is motivated by general enhancements afforded by nanoscale structures that better sustain lattice distortions associated with charge/discharge cycles. We show that preintercalation of alkali metal ions in V-O and Mo-O yields substantial improvement in the Li ion charge/discharge cycling and rate, compared to A-Co-O, A-Mn-O, and A-Fe-P-O. Diffraction and modeling studies reveal that preintercalation with K and Rb ions yields a more stable interlayer expansion, which prevents destructive collapse of layers and allow Li ions to diffuse more freely. This study demonstrates that appropriate alkali metal ion intercalation in admissible structure can overcome the limitation of cyclability as well as rate capability of cathode materials, besides, the preintercalation strategy provides an effective method to enlarge diffusion channel at the technical level, and more generally, it suggests that the optimized design of stable intercalation compounds could lead to substantial improvements for applications in energy storage.
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