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51.
The paper presents the results obtained for the effect of ball milling of Ti–Ni powder, which is close in composition to the equiatomic one, on electrochemical hydrogenation. It is shown that the average size of the powder particles measured by BET and laser diffraction methods is found to reduce during milling, while the average size of the powder particles measured by SEM changes to attain its minimum within 30-s milling due to destruction and subsequent aggregation of particles. The powder in its initial state consists of a mixture of TiNi (austenite, martensite), Ti2Ni, and TiNi3 phases, and after ball milling, an X-ray amorphous phase is formed. The CDD size of the TiNi phase (austenite) reduces from 25 to 4 nm. It is found that the lattice parameters of the TiNi (austenite) and Ni3Ti phases do not change during electrochemical hydrogenation, whereas the crystal lattice parameter of the Ti2Ni phase increases, which indicates the predominant interaction of hydrogen with the Ti2Ni phase. The lattice parameter of the Ti2Ni based phase corresponds to Ti2NiH0.5 and Ti2NiH0.8 hydrides depending on the milling time and hydrogenation time. It is found that there is an “incubation period” of hydrogenation of the Ti2Ni phase, which attains 90 min. 相似文献
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53.
《International Journal of Hydrogen Energy》2021,46(57):29142-29159
Herein, dark fermentation (DF, V = 5.5 L) and subsequent mesophilic methanogenesis (V = 43.5 L) are run as expanded granular sludge bed reactors (EGSB) at thermophilic (υDF = 60 °C) and hyperthermophilic (υDF = 80 °C) temperatures. A synthetic glucose wastewater is run with a 22.5 g/L chemical oxygen demand (COD) and 48–9 h hydraulic retention times (HRTs), giving organic loading rates (OLRs) of 11–60 g COD/L/d for DF. The maximum hydrogen production rate (HPR) is HPR = 3.0 m³/m³/d for HRT = 9 h with a 50 L/kg COD hydrogen yield (HY) and 40 vol% H2. Methane production rate (MPR) reaches MPR = 2.6 m³/m³/d with 70 vol% CH4 at HRT = 2.8 d. The highest H2 yields are HY = 180 L/kg COD with 53 vol% H2 (thermophilic, HRT = 48 h). Hyperthermophilic temperatures led to lower HPRs (0.7 m³/m³/d) and MPRs (1.6 m³/m³/d). 53% of Thermoanaerobacterium thermosaccharolyticum as an H2 producer are found. Discoloration of granular sludge from black to white and granule stability was observed in DF. 相似文献
54.
Like Yue Shixue Wang Takuto Araki Yoshio Utaka Yulin Wang 《International Journal of Hydrogen Energy》2021,46(3):2969-2977
Water management of proton exchange membrane fuel cells remains a prominent issue in research concerning fuel cells. In this study, the gas diffusion layer (GDL) of a fuel cell is partially treated with a hydrophobic agent, and the effect of GDL hydrophobicity on the water distribution in the fuel cell is examined. First, the effect of the position of the cathode GDL hydrophobic area relative to the channel on the fuel cell performance is investigated. Then, the water distribution in the fuel cell cathode GDL is observed using X-ray imaging. The experimental results indicate that when the hybrid GDL's hydrophobic area lies on the channel, water tends to accumulate under the rib, and the water content in the channel is low; this improves the fuel cell performance. When the hydrophobic area is under the rib, the water distribution is more uniform, but the performance deteriorates. 相似文献
55.
The current work introduces an enhancement in the performance of the microbial fuel cell through estimating the optimal set of controlling parameters. The maximization of both power density (PD) and the percentage of chemical oxygen demand (COD) removal were considered as the enhancement in the cell's performance. Three main parameters in terms of performance as well as commercialization are the system's inputs; the Pt which takes the range of 0.1‐0.5 mg/cm2, the degree of sulphonation in sulfonated‐poly‐ether‐ether‐ketone that changes in the range of 20‐80%, and the rate of aeration of cathode which varies between 10 and 150 mL/min. From the experimental dataset, two robust adaptive neuro‐fuzzy inference system models based on the fuzzy logic technique have been constructed. The comparisons between the models' outputs and the experimental data showed well‐fitting in both training and testing datasets. The mean squared errors of the PD model, for testing and whole datasets, were found 2.575 and 0.909 while for the COD model it showed 19.242 and 6.791, respectively. Then, based on the two fuzzy models, a Particle Swarm Optimization algorithm has been used to determine the best parameters that maximize both of the PD and the COD removal of the cell. The optimization process was utilized for single and multi‐object optimization processes. In the single optimization, the resulting maximums of the PD and the COD removal were found 62.844 (mW/m2) and 99.99 (%), respectively. Whereas, in the multi‐object optimization, the values of 61.787 (mW/m2) and 96.21 (%) were reached as the maximums for the PD and COD, respectively. This implies that, in both cases of optimization processes, the adopted methodology can efficiently enhance the microbial fuel cell performances than the previous work. 相似文献
56.
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
57.
58.
Following the recent introduction of the Sustainability over Sets (SOS) concept as a sustainability analysis tool with broad flexibility in incorporating human input, in this work, the concepts of Sustainizability (SIZ) and Sustainizability over Sets (SIZOS) are introduced, as novel frameworks for sustainable system synthesis. Springing off the conceptual foundation of sustainability, SIZ (and SIZOS) refers to the existence of allowable external actions, and/or design changes that can render sustainable (sustainable over a set) an unsustainable (unsustainable over a set) system. Utilizing earlier mathematical results for SOS, rigorous necessary and sufficient conditions for SIZOS are presented. Two case studies, on a two-dimensional biological waste treatment system, and a three-dimensional food chain system, are then presented to illustrate the developed necessary and sufficient conditions for SIZOS. 相似文献
59.
《Planning》2019,(5)
从肺动脉漂浮导管第一次介绍到中国开始,临床血流动力学在我国已经发生了天翻地覆的变化。从监测指标的临床应用,到对血流动力学理论的系统认识;从仅限于循环系统内,到指标遍布整个机体;从对血流动力学无处不在的临床认识,到对重症治疗每一个细节的把控;从对临床治疗与再损伤的认识,到通过血流动力学指标对临床行为的定量管理;终于使血流动力学监测走向治疗。继而,在此基础上,新指标的出现不仅拓宽了视野,并导致对已有体系的重新认识。血流动力学连续与动态特征和目标与目的的实施策略可以付诸实践,才使得"临床血流动力学治疗"的概念,以完整的理论体系、规范的临床应用,终于破茧而出。在深入地植根于临床实践后,今天的临床血流动力学治疗正在从微循环走向器官功能,从个体化走向器官化。 相似文献