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71.
Chun-Sheng Wang Joshua Brinkerhoff 《International Journal of Hydrogen Energy》2021,46(47):24256-24270
A major limitation in chemisorptive hydrogen storage in metal hydrides is the long time required for the adsorption reaction during charging. This study investigates how the shape and material of the reaction chamber influences the adsorption and desorption rates. Numerical simulations of hydrogen storage in a cylindrical reaction chamber filled with LaNi5 hydride are conducted for a range of chamber thermal conductivities and aspect ratios. The results show that adsorption and desorption processes are limited by thermal diffusion in the hydride bed and storage chamber. A storage efficiency is proposed based on an ideal isothermal process and used to evaluate the impact of chamber thermal conductivity and aspect ratio on the adsorption and desorption rates. Empirical correlations are proposed for predicting the adsorption and desorption efficiency of cylindrical LaNi5 hydride beds. Finally, a machine-learning based data model for predicting storage efficiency in metal hydride chambers is presented. Comparison against the empirical correlations highlights that the machine learning-based data model can predict the storage efficiency more accurately. 相似文献
72.
Xuancheng Wang Xuezhang Xiao Jiaguang Zheng Zhouming Hang Wenping Lin Zhendong Yao Meng Zhang Lixin Chen 《International Journal of Hydrogen Energy》2021,46(46):23737-23747
Magnesium borohydride, Mg(BH4)2, is ball-milled with Ti nano-particles. Such catalyzed Mg(BH4)2 releases more hydrogen than pristine Mg(BH4)2 does during isothermal dehydrogenation at 270, 280, and 290 °C. The catalyzed Mg(BH4)2 also exhibits better dehydrogenation kinetics than the pristine Mg(BH4)2. Based on kinetics model fitting, the activation energy (Ea) of the catalyzed Mg(BH4)2 is calculated to be lower than pristine Mg(BH4)2. During partial dehydrogenation, the catalyzed Mg(BH4)2 releases 4.23 wt % (wt%) H2 for the second dehydrogenation at 270 °C, comparing to 4.05, and 3.75 wt% H2 at 280, and 290 °C. The reversibility of 4.23 wt% capacity is also one of the highest for Mg(BH4)2 dehydrogenation under mild conditions such as 270 °C as reported. 4 cycles of Mg(BH4)2 dehydrogenation are conducted at 270 °C. The capacities degrade during 4 cycles and tend to be stable at about 3.0 wt% for the last two cycles. By analyzing the hydrogen de/absorption products of the catalyzed sample, Mg(BH4)2 is found to be regenerated after rehydrogenation according to Fourier Transform Infrared (FTIR) spectroscopy. Ti nano-particles can react with Mg(BH4)2 during ball-milling and de/rehydrogenation. The products include TiH1.924, TiB, and TiB2, which can improve the dehydrogenation properties of Mg(BH4)2 from a multiple aspect. 相似文献
73.
Yue Liu Zhiwen Zhu Fang Liu Jia Xu 《International Journal of Hydrogen Energy》2021,46(31):16667-16675
In this article, the nonlinear dynamic characteristics and bifurcation of a Ti–Zr–Ni quasicrystal impacted by hydrogen atoms are studied. New nonlinear damping terms are proposed to express the delay characteristics of Ti–Zr–Ni quasicrystal, and the accurate natural frequency is obtained by the harmonic balance method. A new method based on the developed largest Lyapunov exponent is proposed to analyze the local stability of any point in the system, and the system's global stability is determined. Finally, a new way to realize the switch between hydrogen storage and release based on stochastic Hopf bifurcation is proposed. The results of theoretical analysis and numerical simulation show that the system's motion can be switched between a periodic orbit and a balanced point near the bifurcation boundary with little energy consumption, which is helpful for hydrogen storage and release. 相似文献
74.
Tareq Salameh Mohammad Ali Abdelkareem A.G. Olabi Enas Taha Sayed Monadhil Al-Chaderchi Hegazy Rezk 《International Journal of Hydrogen Energy》2021,46(8):6014-6027
Renewable energy resources play a very important rule these days to assist the conventional energy systems for doing its function in the UAE due to high greenhouse gas (GHG) emissions and energy demand. In this paper, the analysis and performance of integrated standalone hybrid solar PV, fuel cell and diesel generator power system with battery energy storage system (BESS) or supercapacitor energy storage system (SCESS) in Khorfakkan city, Sharjah were presented. HOMER Pro software was used to model and simulate the hybrid energy system (HES) based on the daily energy consumption for Khorfakkan city. The simulation results show that using SCESS as an energy storage system will help the performance of HES based on the Levelized cost of energy (LCOE) and greenhouse gas (GHG) emissions. The HES with SCESS has renewable fraction (68.1%) and 0.346 $/kWh LCOE. The HES meets the annual AC primary load of the city (13.6 GWh) with negligible electricity excess and with an unmet electrical load of 1.38%. The reduction in GHG emissions for HES with SCESS was 83.2%, equivalent to saving 814,428 gallons of diesel. 相似文献
75.
Jiri Cermak Lubomir Kral Pavla Roupcova 《International Journal of Hydrogen Energy》2021,46(27):14494-14507
Effect of chemical composition of Mg-xCu based alloys (x = 9.94–58.00 wt %) modified by KCl upon their hydrogen storage performance was studied. Kinetic curves and pressure-concentration isotherms were measured in the ranges up to 60 bar and 388 °C, respectively. It was observed that desorption rate dc/dt is not significantly influenced by the composition. Unknown Cu-rich phase was detected that has shown a catalytic effect on desorption from a mixture with other phases. Activation energy of hydrogen desorption decreased with increasing x from 180 kJ/mol down to 98 kJ/mol. Average hydride dissociation enthalpy, ΔH, for the lowest plateau was 75 kJ/mol which is equal to literature value for pure Mg. Slightly lover average value, 67 kJ/mol was obtained for the second plateau and ΔH for the third one decreased from 70 kJ/mol for the lowest to 49 kJ/mol for the highest x. 相似文献
76.
Fatemeh Sadat Razavi Morteza Hajizadeh-Oghaz Omid Amiri Maryam Sadat Morassaei Masoud Salavati-Niasari 《International Journal of Hydrogen Energy》2021,46(1):886-895
The study of the effect of different chelating agents in the Pechini method on the morphology has been a promising strategy that can be used for practical tuning of the nanoparticle's morphology and hence the electrochemical hydrogen storage capacity. In the current study, the conventional Pechini sol-gel approach was used to prepare the Ba2Co9O14 nanoparticles as a novel hydrogen storage material. The X-ray diffraction investigation approved the formation of Ba2Co9O14 with a Hexagonal crystal structure for all of the synthesized samples. The scanning electron microscopy (SEM) revealed when citric acid was used as a chelating agent, nanoparticles with finer and more uniform morphology were obtained rather than other chelating sources. The transmission electron microscopy (TEM) showed in the presence of citric acid; the size of the synthesized nanoparticles was between 14 and 24 nm. According to the Diffuse Reflectance Spectroscopy (DRS) analysis, the calculated bandgap of synthesized nanoparticles was approximately 3.2 eV, which indicates that synthesized nanoparticles were semiconductors in essence. The electrochemical hydrogen adsorption/desorption results showed that the sample synthesized by the citric acid has an enhancement in electrochemical hydrogen storage of approximately 800 mAh/g after 15 cycles. 相似文献
77.
In this study, design and performance analysis is carried out for a 10 kWh metal hydride based hydrogen storage system. The system is equipped with distinctive aluminium hexagonal honeycomb based heat transfer enhancements (HTE) having higher surface area to volume ratio for effective heat transfer combined with low system weight addition. The system performance was studied under different operating conditions. The optimum absorption condition was achieved at 35 bar with water at room temperature as heat transfer fluid where up to 90% absorption was completed in 7200 s. The performance of the reactor was observed to significantly improve upon the addition of the HTE network at a minimal system weight penalty. 相似文献
78.
79.
Yingying Sun Yanshun Xu Pei Gao Wenshui Xia Qian Hua Qixing Jiang 《International Journal of Food Science & Technology》2021,56(1):224-232
To evaluate the effects of irradiation and thermal treatments on the quality characteristics of the vacuum-packaged low-salted fermented fish (Suanyu) during 90-day storage, thermal-treated group (TTG), irradiated-treated group (ITG) and non-treated group (CG) were prepared. The results showed that total viable counts reduced by 4.49 and 4.67 log CFU/g after thermal and irradiation treatments, respectively, and no coliforms and pseudomonas growth occurred during storage. Compared with CG, lower levels in L*, springiness, chewiness of TTG and higher levels in L*, b* and chewiness of ITG were detected after 90-day storage. Total biogenic amines content was significantly reduced in ITG compared with CG and TTG (P < 0.05). Both irradiation and thermal treatments have the potential to maintain quality of Suanyu during room storage. Compared with irradiation, thermal treatment could better stabilise the free amino acids and volatile compounds of Suanyu during room storage, but had some negative effects on texture quality. 相似文献
80.