Mass transfer characteristics for CO₂ absorption in nanoabsorbents

Li, Lirong,Lim, Hwan Suk,Kang, Yong Tae Elsevier 2019 INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER - Vol.129 No.-

<P><B>Abstract</B></P> <P>In this work, an improved VOF-PLIC model is developed to simulate 3D bubble behavior and to analyze the mass transfer characteristics for CO<SUB>2</SUB> absorption in pure methanol and methanol with Al<SUB>2</SUB>O<SUB>3</SUB> nanoparticles. The lower bound boundary value of CO<SUB>2</SUB> volume fraction( <SUB> α g </SUB> ) is redefined according to the influence of <SUB> α g </SUB> on bubble shape and diameter as well as the interfacial area between gas and liquid. In addition, a reasonable drag force is added into the momentum equation using UDF code based on the assumption that the drag force only exists in liquid phase. It is found that the level lines of bubbles with the <SUB> α g </SUB> value of 0.05 agree well with the real case, and the drag force has significant influence on the bubble behavior and mass transfer characteristics. The velocity contours and pressure gradients around the bubble are proposed to analyze the influence of drag force on the mass transfer characteristics. Also, the influence of the Al<SUB>2</SUB>O<SUB>3</SUB> nanoparticles on the mass transfer enhancement is studied, and the results show that the dispersed particles can significantly enhance the mass transfer by increasing the gas–liquid interfacial surface renewal frequency.</P> <P><B>Highlights</B></P> <P> <UL> <LI> An improved VOF-PLIC model is developed to simulate 3D bubble behavior for CO<SUB>2</SUB> absorption in nanoabsorbents. </LI> <LI> Mass transfer characteristics for CO<SUB>2</SUB> absorption in methanol with Al<SUB>2</SUB>O<SUB>3</SUB> nanoparticles is analyzed. </LI> <LI> It is found that the level lines of bubbles with the <SUB> α g </SUB> value of 0.05 agree well with the real case. </LI> <LI> The drag force has an significant influence on the bubble behavior and mass transfer characteristics. </LI> <LI> Gas-liquid interfacial surface renewal frequency significantly increases by adding the nanoparticles. </LI> </UL> </P>

Three-dimensional VOF simulation of bubble behavior and mass transfer for CO₂ absorption in nanoabsorbents

Lirong Li,Yong Tae Kang(강용태) 대한기계학회 2018 대한기계학회 춘추학술대회 Vol.2018 No.4

Calibration of Ductile Fracture Criterion with Optimal Experiment Design and Prediction on Forming Limit for Aluminum Alloy Sheet

Lirong Sun,Zhongyi Cai,Jiaxin Gao,Mingwei Wang,Li Li 대한금속·재료학회 2022 METALS AND MATERIALS International Vol.28 No.4

This paper is concerned with accurate prediction on the fracture strain and fracture forming limit curve (FFLC) by calibratingthe material constants by the specimens with reasonable shapes and sizes. The Lou–Huh ductile fracture criteria (DFC)in analytic and integral forms were adopted, and the theoretical formulas in various stress states were derived. The processand basis for calibrating the material constants of DFC by hybrid experimental–numerical method were described in detail. Moreover, the material constants calculated by different test groups including the uniaxial tensile, plane strain and shearspecimens with different shapes and sizes vary enormously, and the optimal test group was determined to calibrate the materialconstant of DFC. Meanwhile, it can be found that the different material constants greatly impact on the magnitude andshape of the fracture strain and FFLC, and the effect of each material constant on the fracture strain and FFLC was analyzedand compared in this paper. Finally, the FFLCs theoretically calculated by DFC in analytic and integral forms were verifiedby the experimental forming limiting data of the bulge test.

The Research on OA Based On Mobile Telephone

Tao Li,Lirong Qiu 보안공학연구지원센터 2015 International Journal of Future Generation Communi Vol.8 No.1

The global trend of the information and network has changed the peoples’ life and work style. The traditional OA model can’t keep step with the rapid development of the information society. Time and space becomes a main obstacle to the OA. This paper puts forwards a new thought to solve this problem by designing a mobile message module. It can realize mobile OA and may promote the development of the E-government.

The effect of interaction between La2AlCoO6 and CuCl2 on ethane oxychlorination

Lirong Yang,Ruisheng Hu,Huan Li,Yun Jia,Qihua Zhou,Hongye Wang 한국공업화학회 2017 Journal of Industrial and Engineering Chemistry Vol.56 No.-

Supported perovskite-type catalyst La2AlCoO6–CuCl2–g-Al2O3 was synthesized by impregnation–sol– gel–mechanical-mixing methods and characterized by means of XRD, BET, H2-TPR, XPS, O2-TPD and TGDSC techniques. It is found that there is a strong interaction between La2AlCoO6 and CuCl2. The catalyst La2AlCoO6–CuCl2–g-Al2O3 reduces the reduction activation energy of Cu2+! Cu+ and increases the amount of surface adsorbed oxygen species, which are advantageous to the transition of redox group Cu2 +/Cu+, therefore promote the catalytic performance. The catalyst La2AlCoO6–CuCl2–g-Al2O3 shows a superior catalytic activity for ethane oxychlorination with the C2H6 conversion of 100% and the C2H3Cl selectivity to 43.8%.

Network Characteristics Analysis of Microblog Public Opinion

Lirong Qiu,Jie Li,Zhen Hai Zhang,Yi Lei Wang 보안공학연구지원센터 2016 International Journal of Hybrid Information Techno Vol.9 No.10

This paper uses public opinion propagation structure of Sina microblog as research object, it sets up simulation model of public opinion propagation structures based on complex network theory. Through the analysis of the degree distribution, clustering coefficient and community structure of the model, the validity of the model has been well confirmed. The paper also conducts research and analysis towards propagation quantity of the hot topic within 800 well-known spread microblog from 2013 to 2015, the paper establishes a community structure, through the simulation and demonstration of the community structure, it declares the community structure characteristic under the complex network environment.

Behavior of Al/Cu/Ti electrodes in surface acoustic wave filter at high power

Qi Li,Sulei Fu,Zengtian Lu,Lirong Qian,Rui Wang,Tongjin Chen,Cheng Song,Fei Zeng,Weibiao Wang,Feng Pan 한국물리학회 2019 Current Applied Physics Vol.19 No.4

Driven by the need for high data-rates and continuous reduction in device size, surface acoustic wave filters are required to work under increasingly high power. In this work, a series of 2.7 GHz surface acoustic wave filters with Al/Cu/Ti three-layered electrode were fabricated and loaded with high power. Those three-layered electrodes showed weaker texture but higher stability than Al-Cu alloy electrode at high power. Morphologies, microstructures and elements distribution in cross section of fingers were analyzed carefully before and after high power loading. Results show that the circular-arc-shaped outline of fingers were appeared in most samples after high power loading, and the number of gains in the finger cross section changed from some into several with much larger volume. The features of distribution of Cu atoms also coincided with these microstructures. By finite element method and phase diagram analysis, the higher stability of Al/Cu/Ti three-layered electrodes are attributed to precipitation of θ-CuAl2 in the bottom edge of electrode finger and Cu-doped α-Al in the center top.

Removal and fate of carbamazepine in the microbial fuel cell coupled constructed wetland system

Jingyi Xie,Haixiao Li,Shiyu Wang,Hao Chen,Wei Jiang,Lin Zhang,Lianjie Wang,Yufeng Wu,Lirong Li,Xueqiang Lu 대한환경공학회 2022 Environmental Engineering Research Vol.27 No.3

Carbamazepine (CBZ), which is difficult to remove in the wastewater treatment system and easily forms toxic transformation products during the treatment process, is one of the priority pollutants of pharmaceuticals and personal care products (PPCPs). Increasing attention has been paid to explore their treatment technology without side effects from the treatment products. This study aims to reveal the removal and transformation of CBZ in the microbial fuel cell coupled constructed wetland (CW-MFC) system. The CW-MFC system was operated continuously at room temperature for nearly 80 days. The results show that CW-MFC system can effectively remove CBZ with an average removal rate of 97%. Three transformation products were identified by liquid chromatography−high-resolution mass spectrometry: 2-(2-oxoquinazolin-1(2H)-yl) benzoic acid (TP267), methyl 2-(2-oxoquinazolin-1(2H)-yl) benzoate (TP281), 2-(2,4-dioxo-3,4-dihydroquinazolin-1(2H)-yl) benzoic acid (TP283). Except TP281 in the influent, the other transformation products were formed in the system, which indicated that TP267 and TP283 were the main transformation products of CBZ. The formation pathway of transformation products could be explained by reactions including oxidation, hydrolysis, bond rupture and intramolecular reaction. The results also indicate that the CW-MFC system might be a promising technology for PPCPs treatment.

Effect of Sulfur on Microstructures and Solidification Characteristics of a Nickel-Base Single Crystal Superalloy

Shaofeng Chen,Naicheng Sheng,Shigang Fan,Shijie Sun,Guichen Hou,Jinguo Li,Lirong Liu,Yizhou Zhou,Xiaofeng Sun 대한금속·재료학회 2022 METALS AND MATERIALS International Vol.28 No.12

The effects of sulfur on the microstructures and solidification characteristics of a second-generation single crystal superalloywere clarified through optical microscope (OM), scanning electron microscope (SEM), differential scanning calorimetry(DSC) and electron probe microanalysis (EPMA). When sulfur was added to the alloy, the area fraction of theeutectic and microporosity decreased with the area fraction of MC carbides increasing. The γ / γ’ eutectic morphologychanged from mosaic + fan + coarse γ’ to mosaic + fan as the sulfur content increased, and very few γ / γ’ eutectic wasfound in the alloy with the highest sulfur content. Moreover, sulfur tended to segregate at the interdendritic regions andform Hf / Cr- rich sulfides, which were adjacent to the carbides or eutectic. This work not only uncovers some sulfideswrapped by eutectic or carbides, but also presents the solidification sequence of the interdendritic regions in high sulfurcontent alloy was discussed.

DP-LinkNet: A convolutional network for historical document image binarization

( Wei Xiong ),( Xiuhong Jia ),( Dichun Yang ),( Meihui Ai ),( Lirong Li ),( Song Wang ) 한국인터넷정보학회 2021 KSII Transactions on Internet and Information Syst Vol.15 No.5

Document image binarization is an important pre-processing step in document analysis and archiving. The state-of-the-art models for document image binarization are variants of encoder-decoder architectures, such as FCN (fully convolutional network) and U-Net. Despite their success, they still suffer from three limitations: (1) reduced feature map resolution due to consecutive strided pooling or convolutions, (2) multiple scales of target objects, and (3) reduced localization accuracy due to the built-in invariance of deep convolutional neural networks (DCNNs). To overcome these three challenges, we propose an improved semantic segmentation model, referred to as DP-LinkNet, which adopts the D-LinkNet architecture as its backbone, with the proposed hybrid dilated convolution (HDC) and spatial pyramid pooling (SPP) modules between the encoder and the decoder. Extensive experiments are conducted on recent document image binarization competition (DIBCO) and handwritten document image binarization competition (H-DIBCO) benchmark datasets. Results show that our proposed DP-LinkNet outperforms other state-of-the-art techniques by a large margin. Our implementation and the pre-trained models are available at https://github.com/beargolden/DP-LinkNet.