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101.
《International Journal of Hydrogen Energy》2022,47(6):3781-3790
A novel heterostructure of g-C3N4/ZnO/Bi4O5Br2 (ZB-3) was designed, and used in the microbial coupled photocatalytic fuel cell (MPFC). It can effectively improve electron utilization efficiency and pollutant degradation using this double Z-scheme heterojunction structure. The current–time (I–t) curves demonstrated that the current density of ZB-3 was higher than that of ZnO, ZnO/Bi4O5Br2 (ZB-1), g-C3N4/ZnO (ZB-2). Electrochemical impedance spectroscopy (EIS) indicated ZB-3 possessed the minimum charge-transfer resistance. This MPFC for degrading rhodamine B (RhB) and tetracycline (TC) under different conditions were developed using these materials. Even in the dark condition, MPFC with g-C3N4/ZnO/Bi4O5Br2 demonstrated 93% and 82% degradation efficiency for RhB and TC, respectively. Furthermore, the electron transport mechanism of the MPFC and ZB-3 were proposed. It paves the approach for more efficient pollutant degradation via MFC photocatalysis. 相似文献
102.
《International Journal of Hydrogen Energy》2022,47(11):7150-7167
The catalytic partial oxidation (CPO) of methane and iso-octane on Rh-coated monoliths is studied in an adiabatic reactor where axial temperature and concentration profiles are collected by a spatially resolved sampling technique. In CH4-CPO, the Rh/MgAl2O4 outperforms the Rh/α-Al2O3 formulation, due to a significant improvement of Rh dispersion. In iso-octane CPO, the beneficial effect of the improved Rh surface is less important due to the intrinsic lower sensitivity of the system. However, a non-negligible impact of Rh dispersion on the extent of hydrocarbon side-products is observed. This factor, together with the lower acidity of the spinel support, contributes to limit the C build-up. Reactor model and kinetic schemes allow to rationalize the measurements and explore the more general effect of Rh specific surface on the key performance indicators of the CPO reformer, that is syngas productivity and hot-spot temperature. Gas-solid diffusion rate makes such indicators strictly fuel-specific. 相似文献
103.
A methodology for predicting and comparing the full‐scale fire performance of similar materials based on small‐scale testing 下载免费PDF全文
Reconstructive fire testing is an important tool used by fire investigators to determine the cause, origin, and progression of a particular fire. Accurate reconstruction of the fire requires the laboratory structure to be outfitted with materials that, in terms of contribution to fire growth, perform similarly to the original materials found at the fire scene. Therefore, a procedure was developed to enable fire investigators to select these replacement materials on the basis of a quantitative assessment of their relative fire performance. This procedure consists of gram‐scale and/or milligram‐scale standard testing accompanied by inverse numerical modeling of these tests, which is used to obtain relevant material properties. A numerical model composed of a detailed pyrolysis submodel and empirical flame heat feedback submodels, which were developed in this study, is subsequently employed to simulate the early stages of the Room Corner Test, which was selected to represent full‐scale material performance. The results of these simulations demonstrate that this procedure can successfully differentiate between fire growth propensities of several commercially available medium density fiberboards. 相似文献
104.
At present, the major drawback for mobile phones is the issue of power consumption. As one of the alternatives to decrease the power consumption of standard, power-hungry location-based services usually require the knowledge of how individual phone features consume power. A typical phone feature is that the applications related to multimedia streaming utilize more power while receiving, processing, and displaying the multimedia contents, thus contributing to the increased power consumption. There is a growing concern that current battery modules have limited capability in fulfilling the long-term energy need for the progress on the mobile phone because of increasing power consumption during multimedia streaming processes. Considering this, in this paper, we provide an offline meaning sleep-mode method to compute the minimum power consumption comparing with the power-on solution to save power by implementing energy rate adaptation (RA) mechanism based on mobile excess energy level purpose to save battery power use. Our simulation results show that our RA method preserves efficient power while achieving better throughput compared with the mechanism without rate adaptation (WRA). 相似文献
105.
Influence of using as catalysis, Ni-Schiff Base complex which we previously synthesized [1] used to support with amberzyme oxirane resin (A.O.R.) polymer for increasing the catalytic activity in NaBH4 hydrolysis reaction, to hydrogen generation was studied. The prepared catalyst was characterized by using SEM, XRD, BET, FT-IR analyze technique. Polymer supported Ni-Schiff Base complex catalyzed NaBH4 hydrolysis reaction was investigated depending on concentration of NaBH4, concentration of NaOH, temperature, percentage of Ni complex in total polymer supported Ni-Schiff Base complex and amount of catalyst factors. The maximum hydrogen production rate from hydrolysis of sodium borohydride with nickel-based complex catalyst compared to the pure nickel catalyst is increased from 772 mL H2·g?1 cat.·min?1 to 2240 mL H2 g?1 cat.·min?1 [1], and with supported amberzyme oxirane resin polymer this nickel based complex catalyst was increased to 13000 mL H2·g?1 cat.·min?1 at 30 °C. The activation energy of complex catalyzed NaBH4 hydrolysis reaction was found as 25.377 kJ/mol. This work also includes kinetic information for the hydrolysis of NaBH4. 相似文献
106.
Fewer Defects in the Surface Slows the Hydrolysis Rate,Decreases the ROS Generation Potential,and Improves the Non‐ROS Antimicrobial Activity of MgO 下载免费PDF全文
Nemanja Anicˇić Marija Vukomanović Tilen Koklicˇ Danilo Suvorov 《Small (Weinheim an der Bergstrasse, Germany)》2018,14(26)
Magnesium oxide (MgO) is recognised as exhibiting a contact‐based antibacterial activity. However, a comprehensive study of the impact of atomic‐scale surface features on MgO's antibacterial activity is lacking. In this study, the nature and abundance of the native surface defects on different MgO powders are thoroughly investigated. Their impacts on the hydrolysis kinetics, antibacterial activity against Escherichia coli (ATCC 47076), Staphylococcus epidermidis and Pseudomonas aeruginosa and the reactive oxygen species (ROS) generation potential are determined and explained. It is shown that a reduction in the abundance of low‐coordinated oxygen atoms on the surface of the MgO improves its resistance to both hydrolysis and antibacterial activity. The ROS generation potential, determined in‐situ using a fluorescence microplate assay and electron paramagnetic resonance spectroscopy, is not an inherent property of the studied MgO, rather it is a side product of hydrolysis (only for the most highly defected MgO particles) and/or a consequence of the MgO/bacteria interaction. The evaluation of the mutual correlations of the hydrolysis, the antibacterial activity and the ROS generation, with their origin in the surface defects' peculiarities, led to the conclusion that the acid/base reaction between the MgO surface and the bacterial wall contributes considerably to the MgO's antibacterial activity. 相似文献
107.
目的 图像字幕生成是一个涉及计算机视觉和自然语言处理的热门研究领域,其目的是生成可以准确表达图片内容的句子。在已经提出的方法中,生成的句子存在描述不准确、缺乏连贯性的问题。为此,提出一种基于编码器-解码器框架和生成式对抗网络的融合训练新方法。通过对生成字幕整体和局部分别进行优化,提高生成句子的准确性和连贯性。方法 使用卷积神经网络作为编码器提取图像特征,并将得到的特征和图像对应的真实描述共同作为解码器的输入。使用长短时记忆网络作为解码器进行图像字幕生成。在字幕生成的每个时刻,分别使用真实描述和前一时刻生成的字幕作为下一时刻的输入,同时生成两组字幕。计算使用真实描述生成的字幕和真实描述本身之间的相似性,以及使用前一时刻的输出生成的字幕通过判别器得到的分数。将二者组合成一个新的融合优化函数指导生成器的训练。结果 在CUB-200数据集上,与未使用约束器的方法相比,本文方法在BLEU-4、BLEU-3、BLEI-2、BLEU-1、ROUGE-L和METEOR等6个评价指标上的得分分别提升了0.8%、1.2%、1.6%、0.9%、1.8%和1.0%。在Oxford-102数据集上,与未使用约束器的方法相比,本文方法在CIDEr、BLEU-4、BLEU-3、BLEU-2、BLEU-1、ROUGE-L和METEOR等7个评价指标上的得分分别提升了3.8%、1.5%、1.7%、1.4%、1.5%、0.5%和0.1%。在MSCOCO数据集上,本文方法在BLEU-2和BLEU-3两项评价指标上取得了最优值,分别为50.4%和36.8%。结论 本文方法将图像字幕中单词前后的使用关系纳入考虑范围,并使用约束器对字幕局部信息进行优化,有效解决了之前方法生成的字幕准确度和连贯度不高的问题,可以很好地用于图像理解和图像字幕生成。 相似文献
108.
109.
Subhajit Sanfui Deepak Sharma 《International journal for numerical methods in engineering》2020,121(17):3824-3848
With the development of parallel computing architectures, larger and more complex finite element analyses (FEA) are being performed with higher accuracy and smaller execution times. Graphics processing units (GPUs) are one of the major contributors of this computational breakthrough. This work presents a three-stage GPU-based FEA matrix generation strategy with the key idea of decoupling the computation of global matrix indices and values by use of a novel data structure referred to as the neighbor matrix. The first stage computes the neighbor matrix on the GPU based on the unstructured mesh. Using this neighbor matrix, the indices and values of the global matrix are computed separately in the second and third stages. The neighbor matrix is computed for three different element types. Two versions for performing numerical integration and assembly in the same or separate kernels are implemented and simulations are run for different mesh sizes having up to three million degrees of freedom on a single GPU. Comparison with GPU-based parallel implementation from the literature reveals speedup ranging from 4× to 6× for the proposed workload division strategy. Furthermore, the same kernel implementation is found to outperform the separate kernel implementation by 70% to 150% for different element types. 相似文献
110.
Mathematical models for single electrode reversible heat and non-isothermal electromotive force (EMF) of a solid oxide fuel cell (SOFC) are developed. These models estimate the volumetric reversible heat generation and EMF of electrochemical reactions, within each electrode at local conditions of temperature and pressure, based on entropy change of half reactions. The resulting equations are thermodynamically consistent. They inherently obey the conservation of energy law as the electrochemical energy released added to the heat of reactions at each electrode equate the enthalpy change of the reacted species. The equations are implemented to model electrodes in a tubular micro- solid oxide fuel cell (TμSOFC). The thermodynamic consistency of the model is numerically confirmed as the enthalpy of the reactants equates the electric energy released by the cell plus the sum of electrode heats plus electrolyte Ohmic heat. The effect of thermal gradients on the cell's overall EMF is found to be negligible. The reversible and irreversible heat generation of each electrode are distinguished. Overall, the anode is found to be endothermic, and the cathode exothermic. 相似文献