检索结果-内蒙古大学图书馆

Novel Solid-State Hydrolysis Kinetics of Nabh4 for Stable and High-Capacity On-Line Hydrogen Production

学校读者我要写书评

暂无评论

SSRN 2024年

作者： Chen, Jiawei Wu, Zhen Zheng, Jie Shi, Yu Xie, Lei Yang, Fusheng Wang, Yuqi Zhang, Zaoxiao School of Chemical Engineering Northwest University Xi’an710069 China School of Chemical Engineering and Technology Xi’an Jiaotong University Xi’an710049 China College of Chemistry and Molecular Engineering Peking University Beijing100871 China Sunan Institute for Molecular Engineering Peking University Jiangsu 215500 China State Key Laboratory of Multiphase Flow for Power Engineering Xi’an Jiaotong University Xi’an710049 China

Solid-state hydrolysis of NaBH4 could achieve high-capacity on-line hydrogen production. However, the stability of hydrogen production in the solid-state hydrolysis process has been questioned. In this paper, a novel kinetics is proposed for the solid-state hydrolysis behavior. The acceleration factor β is introduced into the traditional shrinking core model to reveal the relationship between "dissolution" and "catalytic hydrolysis" in the solid-state hydrolysis process. The comparison results show a good agreement between the model and experiment in the temperature range of 303.15-348.15 K. Meanwhile, the kinetics conclusions and product characterization indicated that the "excessive dissolution" of NaBH4 and the "dehydration of by-products" are two important factors contributing to the uncontrolled reaction. Based on the parametric analysis and experimental verification, the optimum temperature for solid-state hydrolysis is approximately 323.15 K. Besides, the adjustment of the water intake strategy to intermittent intake reduced water consumption by 36.6%. As a result, the hydrogen release capacity could be increased to as high as 5.49 wt.% (close to the U.S. Department of Energy 2025 gravimetric hydrogen storage capacity of 5.5 wt.%), even though the weight of water is taken into account as reactant. © 2024, The Authors. All rights reserved.

关键词： Hydrolysis

Driving with Clean Footprint: Biodiesel Application and Sustainable Development of the Transportation Sector in China

学校读者我要写书评

暂无评论

SSRN 2023年

作者： Chen, Chuangbin Deng, Chenchen Zhang, Bo Yang, Song Centre for Southeast Asia Studies Shantou University Guangdong Shantou City515063 China Jinhe Center for Economic Research Xi’an Jiaotong University Xianning West Road Shaanxi Xi’an710049 China State Key Laboratory of Multiphase Flow in Power Engineering Xi'an Jiaotong University Shaanxi 710049 China

The advancement of global endeavors to mitigate climate change significantly hinges upon developments within China's transportation sector. This study presents a pioneering examination of the pivotal role of biodiesel as a renewable energy source, accentuating its substantial contributions to China's ambitious objectives of attaining carbon neutrality and reaching the peak of carbon dioxide emissions. Employing the Long-range Energy Alternative Planning System, we formulate five distinct scenarios encompassing the prevailing trend, the promotion of B5 (5% biodiesel blend) and B10 (10% biodiesel blend), China's existing policy framework, policies embraced by the European Union, as well as alternative biofuels. Our analysis reveals that all scenarios exhibit varying degrees of CO2 emissions reduction by the year 2040. The third scenario, driven by China's informal environmental participation, tax incentives, and supportive policies, yields noteworthy outcomes, albeit less substantial in comparison to the EU policy scenario. The B5-B10 scenario presents a more significant reduction in CO2 emissions, although it proves to be less effective in addressing other pollutant emissions in contrast to the alternative biofuel scenario. Furthermore, the adoption of B5-B10 fuels also carries significant economic advantages, with projected emissions reductions amounting to 1.17 trillion yuan (approximately 0.17 trillion dollars) by 2030. Overall, our findings underscore the global implications of China’s low-carbon transportation strategy. The mutually advantageous interactions between formal environmental policies, informal public engagement, and lessons derived from the European Union's policies collectively shape the sustainable development of China's transportation sector. © 2023, The Authors. All rights reserved.

关键词： Sustainable development

Chemical looping based ammonia production--A promising pathway for production of the noncarbon fuel

学校读者我要写书评

暂无评论

Science Bulletin 2022年第20期67卷 2124-2138,M0004页

作者： Qinghua Lai Tianyi Cai Shik Chi Edman Tsang Xia Chen Runping Ye Zhenghe Xu Morris D.Argyle Dong Ding Yongmei Chen Jianji Wang Armistead G.Russell Ye Wu Jian Liu Maohong Fan College of Engineering and Applied Science University of WyomingLaramie WY 82071USA School of Energy and Power Engineering Shanghai Key Laboratory of Multiphase Flow and Heat Transfer in Power EngineeringUniversity of Shanghai for Science and TechnologyShanghai 200093China Wolfson Catalysis Department of ChemistryUniversity of OxfordOxford Ox13QRUK College of Chemistry and Chemical Engineering Ocean University of ChinaQingdao 266100China State Key Laboratory of Catalysis Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023China Department of Materials Science and Engineering Southern University of Science and TechnologyShenzhen 518055China Department of Chemical and Materials Engineering University of AlbertaEdmonton Alberta T6G1H9Canada Department of Chemical Engineering Brigham Young UniversityProvo UT 84602USA Idaho National Laboratory Idaho Falls ID83415USA College of Chemistry Beijing University of Chemical TechnologyBejing 100029China School of Chemistry and Environmental Science Henan Normal UniversityXinxiang 453007China School of Civil and Environmental Engineering Georgia Institute of TechnologyAtlanta GA 30332USA MIIT Key Laboratory of Thermal Control of Electronic Equipment School of Power EngineeringNanjing University of Science&TechnologyNanjing 210094China DICP-Surrey Joint Centre for Future Materials Department of Chemical and Process Engineeringand Advanced Technology InstituteUniversity of SurreyGuilford Surrey GU27XH UK

Ammonia, primarily made with Haber-Bosch process developed in 1909 and winning two Nobel prizes, is a promising noncarbon fuel for preventing global warming of 1.5 °C above pre-industrial levels. However,the undesired characteristics of the process, including high carbon footprint, necessitate alternative ammonia synthesis methods, and among them is chemical looping ammonia production(CLAP) that uses nitrogen carrier materials and operates at atmospheric pressure with high product selectivity and energy efficiency. To date, neither a systematic review nor a perspective in nitrogen carriers and CLAP has been reported in the critical area. Thus, this work not only assesses the previous results of CLAP but also provides perspectives towards the future of CLAP. It classifies, characterizes, and holistically analyzes the fundamentally different CLAP pathways and discusses the ways of further improving the CLAP performance with the assistance of plasma technology and artificial intelligence(AI).

关键词： Ammonia synthesis Chemical looping Nitrogen carrier Renewable fuels Energy carrier

Spatial Heterogeneity of Point Defect Properties in Refractory Multi-Principal Element Alloy with Short-Range Order: A First-Principles Study

学校读者我要写书评

暂无评论

SSRN 2022年

作者： Shi, Tan Lyu, Sixin Su, Zhengxiong Wang, Yunpeng Qiu, Xi Sun, Dan Xin, Yong Li, Wenjie Cao, Jiang Peng, Qing Li, Yuanming Lu, Chenyang School of Nuclear Science and Technology Xi’an Jiaotong University Xi’an710049 China Nuclear Power Institute of China Chengdu610213 China Science and Technology on Reactor System Design Technology Laboratory Nuclear Power Institute of China Chengdu610213 China School of Electronic and Optical Engineering Nanjing University of Science and Technology Nanjing210094 China State Key Laboratory of Nonlinear Mechanics Institute of Mechanics Chinese Academy of Sciences Beijing100190 China State Key Laboratory of Multiphase Flow in Power Engineering Xi’an Jiaotong University Xi’an710049 China

The short-range order is inherently present in the multi-principal element alloys and has a profound impact on the defect behaviour. The effect of short-range order on vacancy and interstitial formation and migration was studied in body-centered cubic multi-principal element alloy NbZrTi by first-principles calculations. Two short-range order structures created by density functional theory and Monte Carlo method at 500 K and 800 K were compared with the random solid solution structure. Both vacancy and interstitial formation energies increase with the degree of short-range order. Point defect formation energies tend to be higher in region enriched in Nb and lower in region enriched in Zr and Ti. Both vacancies and interstitials prefer to migrate towards Zr,Ti-rich regions and away from Nb-rich regions, suggesting that Zr,Ti-rich region can act as recombination center for point defect annihilation. Compared to the random solid solution, the short-range order increases the spatial heterogeneity of point defect energy landscape. Tuning the degree of short-range order can be a viable strategy to optimize the point defect behaviour to achieve enhanced radiation resistance in multi-principal element alloys. © 2022, The Authors. All rights reserved.

关键词： Monte Carlo methods

Modeling of water and temperature distribution in PEM fuel cell

学校读者我要写书评

暂无评论

Kung Cheng Je Wu Li Hsueh Pao/Journal of engineering Thermophysics 2010年第12期31卷 2051-2056页

作者： Ma, Li-Zhong Shen, Shuang-Lin Jia, Fei Liu, Hong-Tan Guo, Lie-Jin State Key Laboratory of Multiphase Flow in Power Engineering Xi'an Jiaotong University Xi'an 710049 China Dept. of Mechanical and Aerospace Engineering University of Miami Coral Gables FL 33124 United States

A two-phase flow, non-isothermal, three dimensional model was developed to study the transport phenomena in proton exchange membrane (PEM) fuel cell. Modeling results of water distribution and temperature distribution are presented in this paper. The modeling results show that water and temperature distributions are non-uniform. Along the flow direction, water concentration in anode is decreasing while that in cathode is increasing which liquid water present in cathode;in the cross section perpendicular to the flow direction, both water concentration and liquid water saturation under the shoulder are higher than that under the channel;liquid water distribution across cathode GDL is different at different discharging voltages. Local temperature is decreasing along the flow direction, with even higher gradient when the reactant gas is insufficient;temperatures under the shoulder are lower than those under the channel;in the direction across MEA, the highest temperature is in cathode catalyst layer, and temperature gradient increases as the discharging voltage decreases;at the same discharging voltage, the thicker the PEM is, the lower the local temperatures and the temperature gradient across MEA are.

关键词： Temperature distribution

Effects of Flue Gas Recirculation on Combustion and Heat Flux Distribution in 660 Mw Double-Reheat Tower-Type Boiler

学校读者我要写书评

暂无评论

SSRN 2022年

作者： Deng, Lei Dong, Lingxiao Bai, Yang Wu, Yuhao Liu, Hu Belošević, Srdjan Tomanović, Ivan Che, Defu State Key Laboratory of Multiphase Flow in Power Engineering School of Energy and Power Engineering Xi’an Jiaotong University Xi’an710049 China Guoshen Institute of Technology CHN ENERGY Xi'An710065 China Department of Thermal Engineering and Energy "VINČA" Institute of Nuclear Sciences National Institute of thе Republic of Serbia University of Belgrade Mike Petrovića Alasa 12-14 11351 Vinča PO Box 522 Belgrade11001 Serbia

The ultra-supercritical double-reheat boiler has attracted more attention because of high parameters, low pollution and large capacity. However, there are some difficulties in the development of this technology, such as adjusting the reheat steam temperature. In this study, computational fluid dynamics simulation is used to analyze a 660 MW double-reheat tower-type pulverized coal-fired boiler. The influence of flue gas recirculation (FGR) on heat transfer characteristics and combustion process in the furnace (including heating surfaces in the upper parts of the furnace) are evaluated. The user-defined function approach predicates CO reduction effect on NO x . The results show that the flow at the horizontal section through the centerline of recirculating flus gas nozzles is rotating. The velocity distribution changes into an elliptical rotating flow when FGR ratio is 20%. At higher FGR ratios, the high-temperature area (1565-1700 K) shrinks and both the NO x concentration at the low-temperature superheater outlet and oxygen concentration in the furnace descend. Oxygen concentration at low-temperature superheater outlet first increases and then decreases. In the main combustion zone, the heat flux peak of water-cooled wall is about 330 kW m -2 . As FGR ratio increases from 0% to 20%, the rate of water-cooled wall heat absorption to total boiler decreases by 3.50%. This rate for reheater and superheater increases by 2.53% and 2.13%, respectively. © 2022, The Authors. All rights reserved.

关键词： Temperature

Numerical Investigations for the Pcm and Liquid Immersion Cooling Effects on Lithium Ion Battery Thermal Runaway Mitigation

学校读者我要写书评

暂无评论

SSRN 2023年

作者： Liu, Xinyu Zhou, Zhifu Wu, Wei-Tao Wei, Lei Wu, Weixiong Li, Yang Gao, Linsong Li, Yubai Song, Yongchen Key Laboratory of Ocean Energy Utilization and Energy Conservation of Ministry of Education Dalian University of Technology Dalian116024 China State Key Laboratory of Multiphase Flow in Power Engineering Xi'an Jiaotong University Xi’an710049 China School of Mechanical Engineering Nanjing University of Science and Technology Nanjing210094 China Department of Mechanical and Energy Engineering Southern University of Science and Technology Shenzhen518055 China Energy and Electricity Research Center Jinan University Zhuhai519070 China

In this study, a three-dimensional (3D) thermal runaway (TR) model with conjugate heat transfer submodel is adopted. TR behaviors for a battery pack with 12 prismatic LIBs are then simulated. Three thermal safety measures of TR protection from internal shorting in Cell 1 to pack level configuration are compared and evaluated. Paraffin phase change material (PPCM) is firstly proposed to delay the TR propagation between LIBs with solid-liquid phase change as heat transfer mechanism. Different thicknesses of PPCMs are compared to verify the TR mitigation performance of the PPCM under thermal abuse condition. The TR time for the Cell 2 is delayed to be 64 s, 266 s and 414 corresponding to PPCM thickness of 1.8 mm, 3.6 mm and 5.4 mm. As the simulation results shows, this TR time can be further delayed to 798 s by a strategy with combing PPCM with insulation. In addition, this work proposes a novel thermal safety protection based on immersion cooling with pool boiling of fluorinated liquid as heat transfer mechanism. We observe that the average temperature of Cell 2 - Cell 12 tends to be within 34oC under immersive cooling condition, which indicates the possibility to prevent the TR. © 2023, The Authors. All rights reserved.

关键词： Lithium-ion batteries

Corrigendum to ‘Numerical simulation on sonic steam jet condensation in subcooled water through a double-hole nozzle’ [Int. J. Heat Mass Transfer 115 (2017) 143–147]

学校读者我要写书评

暂无评论

International Journal of Heat and Mass Transfer 2017年 115卷 1360-1360页

作者： Lutao Wang Daotong Chong Lun Zhou Weixiong Chen Junjie Yan State Key Laboratory of Multiphase Flow in Power Engineering Xi’an Jiaotong University Xi’an 710049 PR China

Experimental study on the submerged steam jet through side hole nozzle

学校读者我要写书评

暂无评论

IOP Conference Series: Materials Science and engineering 2015年第1期88卷

作者： W Wang F Yuan Q B Zhao D T Chong W X Chen J J Yan State Key Laboratory of Multiphase Flow in Power Engineering Xi'an Jiaotong University Xi'an 710049 PR China

In this paper, the steam shape parameters and the condensation oscillation characteristics of the direct contact condensation of submerged steam jet into subcooled water were investigated through a side hole nozzle. Meanwhile, the dimensionless jet length and the expansion ratio versus pool water temperature and steam mass flux were obtained by measuring the photographs taken by a high speed camera. Both of them increased gradually with rise of pool water temperature and steam mass flux. A comparison of the shape parameters of three different style nozzles was also achieved. And a correlation of the dimensionless jet length was obtained, the predicted data agreed well with the experimental data, while the discrepancy was within ±5%. For the pressure oscillation versus steam mass flux, the peaks and the root mean square value of pressure oscillation were almost consistent in the range of 150-400 kgm-2s-1, while both of them increase in the range of 400-800 kgm-2s-1. The positive peak and negative peak were completely symmetrical.

关键词：