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21.
《International Journal of Hydrogen Energy》2021,46(55):28064-28077
Hydrogen generation through solar-water splitting is expected to address the global energy crisis by providing a source for a safer and sustainable alternative fuel. Herein, we report a facile synthesis of Cu2O nanowires and show that the magnetic field could influence the nanowires’ distribution and alignment. Orientation of nanowires was observed to become more inclined towards the magnetic field lines as the values of full-width at half maximum decreased from 140° to 46.2° with the increase in the field strength. Crystallographic, morphological, optoelectronic, and photoelectrochemical properties of the constructed p-n homojunction were analyzed by using different characterization techniques. A high built-in potential of +0.93 V vs. RHE was observed for a 50 nm layer of n-Cu2O over p-Cu2O nanowires that resulted in a significantly high photocurrent density of −7.42 mA/cm2. The stability in the photoelectrochemical medium was maintained for 14 h, generating 20 mmol/cm2 of H2. 相似文献
22.
This paper considers thermochemical recuperation (TCR) of waste-heat using natural gas reforming by steam and combustion products. Combustion products contain steam (H2O), carbon dioxide (CO2), and ballast nitrogen (N2). Because endothermic chemical reactions take place, methane steam-dry reforming creates new synthetic fuel that contains valuable combustion components: hydrogen (H2), carbon monoxide (CO), and unreformed methane (CH4). There are several advantages to performing TCR in the industrial furnaces: high energy efficiency, high regeneration rate (rate of waste-heat recovery), and low emission of greenhouse gases (CO2, NOx). As will be shown, the use of TCR is significantly increasing the efficiency of industrial furnaces – it has been observed that TCR is capable of reducing fuel consumption by nearly 25%. Additionally, increased energy efficiency has a beneficial effect on the environment as it leads to a reduction in greenhouse gas emissions. 相似文献
23.
Tunneling nanotubes (TNTs) are recognized long membrane nanotubes connecting distance cells. In the last decade, growing evidence has shown that these subcellular structures mediate the specific transfer of cellular materials, pathogens, and electrical signals between cells. As intercellular bridges, they play a unique role in embryonic development, collective cell migration, injured cell recovery, cancer treatment resistance, and pathogen propagation. Although TNTs have been considered as potential drug targets for treatment, there is still a long way to go to translate the research findings into clinical practice. Herein, we emphasize the heterogeneous nature of TNTs by systemically summarizing the current knowledge on their morphology, structure, and biogenesis in different types of cells. Furthermore, we address the communication efficiency and biological outcomes of TNT-dependent transport related to diseases. Finally, we discuss the opportunities and challenges of TNTs as an exciting therapeutic approach by focusing on the development of efficient and safe drugs targeting TNTs. 相似文献
24.
介绍提高AutoForm软件分析效率的两种途径,分别是:针对每个零件制作各自的设置模板文件,通过引用模板文件,减少操作步骤,可节约分析时间15 min,同时将分析文件的存储空间减小到原来的45%左右;针对每个零件建立模面控制线数据库,通过引用控制线数据库,将拉延模面的建立的效率提高了20%,进而提高了整体分析效率。 相似文献
25.
Full-fluorescence organic light-emitting diodes (FOLEDs) with low cost and high efficiency are imperious demands for commercial process in flat panel display and lighting products. We fabricated a series of FOLEDs employing C545T and DCJTB as doped dyes and different exciplex blends as cohosts. The results proved that reverse intersystem crossing (RISC) efficiency of exciplex cohost has a significant effect on the device performance. Devices with TAPC:PIM-TRZ as cohost which possessed the highest RISC efficiency showed the best results. The green FOLEDs exhibited the maximum external quantum efficiencies (EQEs) approaching to 20%, the red FOLEDs exhibited EQEs over 10% and all the EQE roll-offs are less than 10% at 1000 cd m−2, which are among the best reported results so far, suggesting these exciplex cohosts are promising for FOLEDs. 相似文献
26.
气溶胶池洗过滤是反应堆严重事故中去除放射性源项的重要手段。本文以严重事故条件下上升气泡中气溶胶的滞留过程为背景,设计搭建了可视化单气泡鼓泡实验装置。通过该装置研究了气溶胶在上升气泡中的沉降效率,并与MELCOR中的气溶胶沉降模型计算结果进行了对比。结果表明,气溶胶沉降效率对气泡尺寸的变化较为敏感,当气体流量大于0.1 L/min时,气泡等效直径迅速增加,相应的气溶胶沉降效率快速降低;与MELCOR模型计算结果的对比表明,两者在总体趋势上呈现出较好的一致性,但计算结果低估了液相对气溶胶的实际去除能力,导致这种偏差的主要原因是气泡在上升过程中存在无规则的晃动以及气液界面的波动。 相似文献
27.
本文使用Prophet人工智能算法研究与预测移动通信网络“潮汐效应”现象,探索网络“潮汐效应”在优化网络资源配置实现网络降本增效的作用。Prophet人工智能算法是一种简单、有效,且易于实现的人工智能算法。通过facebook的人工智能开源框架fbprophet,研究4G网络PRB利用率等网络资源指标的“潮汐效应”,并预测这些网络资源指标在未来的变化趋势,用来指导当前4G网络减容、扩容和4/5G节电节能等,实现优化网络资源配置达到降本增效的目的。 相似文献
28.
《Ceramics International》2022,48(13):18278-18285
We report the improved energy storage density and efficiency after 2.5% of Samarium substitution in ferroelectric Pb[(Mg1/3Nb2/3)0.80Ti0.20]O3 (PMNT) electroceramic. The microstructure and surface morphology were analyzed and correlated with various functional properties. The energy storage density, leakage current density, ferroelectric and dielectric properties were investigated thoroughly, indicating that Samarium's substitution significantly modified the microstructure, the dielectric strength, breakdown electric field, and turned ferroelectric PMNT to relaxor ferroelectrics. Due to the relaxor nature, the gap between remanent polarization and maximum polarization increases with the substitution of Samarium in PMNT matrix, which further increases the recoverable energy storage density and energy efficiency. A nearly 100% increase in recoverable energy density and efficiency was obtained at an electric field strength of 35 kV/cm at room temperature (~296 K). The electroceramic shows maximum energy density near the ferroelectric phase transition temperature (325 K–345 K) region and provides a moderate energy storage density for possible applications in power microelectronics. 相似文献
29.
A novel spiral micromixer with sinusoidal channel walls was designed to enhance the mixing index in the low to intermediate Reynolds number range (1 < Re < 100). To analyze the fluid flow, a set of numerical simulations were performed using the finite-difference method. The microchip was fabricated from polydimethylsiloxane, employing the soft-lithography technique. The degree of mixing was increased by 99.11 % when using the proposed micromixer, compared to 59.44 % for a simple spiral micromixer. The introduced microchannel drastically reduced the mixing length, increasing the mixing index of a 0.5-loop spiral-sinusoidal microchannel compared to that of the simple spiral microchannel with 1.5 loops. The mixing index of the 3-loop mixer was higher than that of the microchannel with 1.5 loops, and its pressure drop was increased. 相似文献
30.
ABSTRACTThis article examines equity concerns and inherent conflicts related to rural–urban water supply allocation and use, with focus on Metro Manila. Going beyond the much-discussed difficulty farmers experience from an allocation policy prioritizing urban water requirements, it shows that inequity in raw water allocation is linked to, and further exacerbated by, inequities in urban domestic water provision. Moreover, it highlights the need for broader equity reviews, using the concept of the rural–urban water equity nexus to draw attention to key equity considerations across space and scale that otherwise might remain invisible. 相似文献