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81.
Thermal management and catalytic combustion stability characteristics of premixed methane/air in heat recirculation meso‐combustors 下载免费PDF全文
Yunfei Yan Shuai Feng Zizhen Huang Li Zhang Wenli Pan Lixian Li Zhongqing Yang 《国际能源研究杂志》2018,42(3):999-1012
In order to illuminate heat recirculation effect on catalytic combustion stability and further improve energy conversion efficiency in meso‐combustor, the catalytic combustion characteristics of the combustor with/without preheating channels are numerically studied at steady conditions. It is found that methane conversion rate and combustion efficiency increases by 2% to 3% and approximately 9% in the heat recirculation meso‐combustor, indicating that heat recirculation effect facilitates more complete combustion of methane and medium components. Preheating channels show positive effects on improving combustion stability in the heat recirculation meso‐combustor. On one hand, preheating channels facilitate heat recirculation effect, and heat recirculation rate exceeds 10% for all cases and reaches 31.8% with an inlet velocity of 0.5 m/s, leading to significant increment of methane‐specific enthalpy at the preheating channel outlet. On the other hand, Rh(s)/O(s) ratios of catalytic surface and catalytic surface temperature in main reaction zone are enlarged by the preheating channels, facilitating methane adsorption at catalytic surface. Specially, most of fuels are consumed in a shorter distance with higher methane conversion speed, which brings benefits to promote combustion efficiency and may be helpful to inhibit the combustion instability in heat recirculation meso‐combustors. 相似文献
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83.
Rajiv K. Bedi Dr. Danzhi Huang Stefanie A. Eberle Dr. Lars Wiedmer Dr. Pawel Śledź Prof. Amedeo Caflisch 《ChemMedChem》2020,15(9):744-748
The RNA methylase METTL3 catalyzes the transfer of a methyl group from the cofactor S-adenosyl-L-methionine (SAM) to the N6 atom of adenine. We have screened a library of 4000 analogues and derivatives of the adenosine moiety of SAM by high-throughput docking into METTL3. Two series of adenine derivatives were identified in silico, and the binding mode of six of the predicted inhibitors was validated by protein crystallography. Two compounds, one for each series, show good ligand efficiency. We propose a route for their further development into potent and selective inhibitors of METTL3. 相似文献
84.
Xiuhui Huang Junfeng Li Jun Wang Zeqiu Li Jiayin Xu 《Frontiers of Chemical Science and Engineering》2020,14(4):534
In the last decades, many reports dealing with technology for the catalytic combustion of methane (CH4) have been published. Recently, attention has increasingly focused on the synthesis and catalytic activity of nickel oxides. In this paper, a NiO/CeO2 catalyst with high catalytic performance in methane combustion was synthesized via a facile impregnation method, and its catalytic activity, stability, and water-resistance during CH4 combustion were investigated. X-ray diffraction, low-temperature N2 adsorption, thermogravimetric analysis, Fourier transform infrared spectroscopy, hydrogen temperature programmed reduction, methane temperature programmed surface reaction, Raman spectroscopy, electron paramagnetic resonance, and transmission electron microscope characterization of the catalyst were conducted to determine the origin of its high catalytic activity and stability in detail. The incorporation of NiO was found to enhance the concentration of oxygen vacancies, as well as the activity and amount of surface oxygen. As a result, the mobility of bulk oxygen in CeO2 was increased. The presence of CeO2 prevented the aggregation of NiO, enhanced reduction by NiO, and provided more oxygen species for the combustion of CH4. The results of a kinetics study indicated that the reaction order was about 1.07 for CH4 and about 0.10 for O2 over the NiO/CeO2 catalyst. 相似文献
85.
Liqiang Ren Shujie Yang Peiran Zhang Zhiguo Qu Zhangming Mao Po‐Hsun Huang Yuchao Chen Mengxi Wu Lin Wang Peng Li Tony Jun Huang 《Small (Weinheim an der Bergstrasse, Germany)》2018,14(40)
Microfluidic fluorescence‐activated cell sorters (μFACS) have attracted considerable interest because of their ability to identify and separate cells in inexpensive and biosafe ways. Here a high‐performance μFACS is presented by integrating a standing surface acoustic wave (SSAW)‐based, 3D cell‐focusing unit, an in‐plane fluorescent detection unit, and an SSAW‐based cell‐deflection unit on a single chip. Without using sheath flow or precise flow rate control, the SSAW‐based cell‐focusing technique can focus cells into a single file at a designated position. The tight focusing of cells enables an in‐plane‐integrated optical detection system to accurately distinguish individual cells of interest. In the acoustic‐based cell‐deflection unit, a focused interdigital transducer design is utilized to deflect cells from the focused stream within a minimized area, resulting in a high‐throughput sorting ability. Each unit is experimentally characterized, respectively, and the integrated SSAW‐based FACS is used to sort mammalian cells (HeLa) at different throughputs. A sorting purity of greater than 90% is achieved at a throughput of 2500 events s?1. The SSAW‐based FACS is efficient, fast, biosafe, biocompatible and has a small footprint, making it a competitive alternative to more expensive, bulkier traditional FACS. 相似文献
86.
Li Lanhui Lv Tiejun Huang Pingmu Mathiopoulos P. Takis 《Journal of Signal Processing Systems》2020,92(12):1421-1435
Journal of Signal Processing Systems - For vehicles with limited computation resources offloading their computational tasks to a mobile edge computing (MEC) server has been studied in the past as... 相似文献
87.
自动铺带技术是一种增量制造技术,适用于制造翼面、壁板等大尺寸、小曲率复合材料构件,具有加工成本低、效率高等特点。轨迹规划是自动铺带技术的关键环节,它直接关系到复合材料构件的成型精度与质量。现有的自动铺带轨迹规划方法难以便捷兼顾调控铺放间隙与防止铺放褶皱,保证铺带产品的最终质量。有鉴于此,提出了一种基于近似测地线的分层次铺放轨迹规划方法。主要目标是合理利用预浸带允许变形能力,在防止铺放褶皱产生的前提下,保证相邻带料不产生覆盖,且间隙不超过2.5 mm。首先,研究了铺放间隙的产生与演化规律,给出了几种典型曲面上初始铺放间隙的优化方法。接下来,提出了近似测地线的数学模型与求解格式。然后,基于铺放褶皱的产生机制与铺放间隙的演化规律,确定了近似测地线的测地曲率大小与符号。最后,在双曲面模具以及自由曲面模具上验证了所提出方法的有效性。 相似文献
88.
本文通过对两级伸缩式液压缸与四柱滑轨结合使用中所出现问题及处理过程的阐述,提出了在液压系统设计与制造中,准确的原理仅仅是基础,其上还有许许多多的细枝末节需要仔细修剪,比如污染、噪声、温度、泄漏以及与机械的协调等等。 相似文献
89.
Nader Tehrani Dan Gallagher Monica Ponce de Leon Harry Lowd Richard Lee Lisa Huang Remon Alberts Janghwan Cheon Jumanah Jamal Aishah Al Sager 《世界建筑导报》2018,(2)
正Banq餐厅位是一家新型餐厅,位于便士储蓄银行(Penny Savings Bank)旧大楼以前用来经营银行业务的大厅内。餐厅分成两个部分,前面区域面向华盛顿大街,设计成酒吧,后面的大厅则作为用餐区。然而,这个空间在z轴上以天花板和地面之间的另一个分区为中心进行设计。如果由于餐厅空间活动的多变性而需要保持灵活性——包括两个座位、四个座位和六个座位,以及与聚会和其他活动有关的座位 相似文献
90.