Experimental studies of bubble cutting in a lab-scale micro-structured bubble column with different liquid viscosity

Guanghui Chen,Zhongcheng Zhang,Fei Gao,Jianlong Li,Jipeng Dong 한국화학공학회 2022 Korean Journal of Chemical Engineering Vol.39 No.8

Bubble cutting was realized by installing a wire mesh in a micro-structured bubble column (MSBC) andstudied experimentally with liquid viscosity range from 1 to 39.6mPa·s. A non-intrusive high-speed camera methodwas used to determine bubble size and size distribution. The changes of gas holdup, bubble size, size distribution andSauter mean diameter before and after cutting were systematically studied with mesh openings of 3.8mm and 5.5mm. Three novel bubble cutting behaviors with uniform cutting, detachment cutting and indirect cutting behavior wereobserved. In the presence of two wire meshes, the bubble size distribution roughly shows a Gaussian curve distributionand the peak tends to shift towards lower diameters. With increasing liquid viscosity and superficial gas velocity,the dominant peak tends to move towards higher diameters, resulting in poor mesh cutting effect. After cutting, in thecase of two wire meshes, the Sauter mean diameter decreased by 33.5% and 22.2% and the gas holdup increased by3.2-12.2% and 1.2-4.4%, respectively. For the case of 3.8 mm mesh opening, the interfacial area increased by 10-26%,which is much better than 5.5mm mesh. The mean bubble size above the mesh will grow again and its growth ratedepends on the liquid viscosity.

Facile fabrication of copper oxide modified activated carbon composite for efficient CO2 adsorption

Guanghui Chen,Fei Wang,Shougui Wang,Cailin Ji,Weiwen Wang,Jipeng Dong,Fei Gao 한국화학공학회 2021 Korean Journal of Chemical Engineering Vol.38 No.1

Copper oxide modified activated carbon (CuO/AC) composites for the CO2 capture were synthesized via a facile assembly strategy associated with a direct solid-state heat dispersion process by introducing CuO into AC using Cu(NO3)2 as the copper source. The synthesized CuO/AC composites with various CuO contents were characterized by powder X-ray diffraction, scanning electron microscopy and nitrogen adsorption-desorption measurement, and the CO2 adsorption performance was investigated. The characterization results indicate that the Cu(NO3)2 species was well dispersed into the AC pore channels and then converted to a highly dispersed CuO after the activation process. The adsorption results reveal that the CO2 adsorption performance can be significantly improved by introducing CuO onto the AC surfaces, and the CuO(0.6)/AC composite with a CuO loading of 0.6mmol/g AC shows a high CO2 adsorption capacity and adsorption selectivity and displays an excellent reversibility. Additionally, the calculated adsorption heat values of CO2 on the CuO(0.6)/AC composite are in the range of 27.3 to 33.9 kJ/mol.

China Consensus Document on Allergy Diagnostics

Chen Hao,Li Jing,Cheng Lei,Gao Zhongshan,Lin Xiaoping,Zhu Rongfei,Yang Lin,Tao Ailin,Hong Haiyu,Tang Wei,Guo Yinshi,Huang Huaiqiu,Sun Jinlyu,Lai He,Lei Cheng,Liu Guanghui,Xiang Li,Chen Zhuanggui,Ma Ha 대한천식알레르기학회 2021 Allergy, Asthma & Immunology Research Vol.13 No.2

The prevalence of allergic diseases has increased dramatically in recent years in China, affecting the quality of life in 40% of the population. The identification of allergens is the key to the diagnosis of allergic diseases. Presently, several methods of allergy diagnostics are available in China, but they have not been standardized. Additionally, cross-sensitization and co-sensitization make allergy diagnostics even more complicated. Based on 4 aspects of allergic disease (mechanism, diagnosis procedures, allergen detection in vivo and in vitro as well as the distribution map of the most important airborne allergens in China) and by referring to the consensus of the European Society of Allergy and Clinical Immunology, the World Allergy Organization, and the important literature on allergy diagnostics in China in recent years, we drafted this consensus of allergy diagnostics with Chinese characteristics. It aims to standardize the diagnostic methods of allergens and provides a reference for health care givers. The current document was prepared by a panel of experts from the main stream of professional allergy associations in China.

Optimization of annealing treatment parameters in a twin roll cast and warm rolled ZK60 alloy sheet

Chen, Hongmei,Yu, Huashun,Kang, Suk Bong,Cho, Jae Hyoung,Min, Guanghui Elsevier 2010 Materials science & engineering. properties, micro Vol.527 No.4

<P><B>Abstract</B></P><P>The microstructure of twin roll cast and warm rolled ZK60 alloy sheet was investigated using OM and TEM technique after annealing treatment at the temperature ranging from 300°C to 400°C. Tensile test at room temperature was performed to show the influence of annealing treatment on mechanical properties. Static recrystallization (SRX) was observed during annealing treatment of ZK60 alloy sheet at and above 300°C. Shear bands, dislocations and twins play an important role during static recrystallization and serve as nucleation sites. Disc-shaped precipitates could be found in annealed ZK60 alloy sheet. Higher temperature annealing treatment resulted in higher density precipitates, and at this condition the dispersion strengthening particles improved the ability of resistance to softening at elevated temperature. Annealing treatment at 375°C for 10<SUP>3</SUP>s can be considered to be the optimum annealing treatment, and under this condition the tensile strength, yield strength and elongation are 388MPa, 301MPa and 22.9%, respectively.</P>

Optimistic Fault Diagnosis in Discrete Event Systems by Labeled Petri Nets and Basis Markings

Guanghui Zhu,Jiafeng Zhang,Zhong Zheng,Shan Luan,Te Chen,Qiang Ma,Zhiwu Li 제어·로봇·시스템학회 2022 International Journal of Control, Automation, and Vol.20 No.6

This paper deals with the fault diagnosis problem of discrete event systems modeled with labeled Petri nets. Its main contributions are threefold. First, depending on whether a diagnosis function examines the fault transitions that possibly occur after the last observed event, we formally divide the diagnosis functions into two types: optimistic and pessimistic, which aims to facilitate the exploration of different diagnosis approaches. Second, a framework is proposed, which extends a given diagnosis approach for Petri nets to the case of labeled Petri nets. The main idea of the framework is to compute and combine the diagnosis results of observable transition sequences corresponding to an observed word. Third, we convert a basis-marking-based approach that is originally pessimistic to the optimistic case and prove the correctness of this conversion.

Dissecting the meteorological and genetic factors affecting rice grain quality in Northeast China

Chen Mojun,Li Zhao,Huang Jie,Yan Yongfeng,Wu Tao,Bian Mingdi,Zhou Jinsong,Wang Yongjun,Lyv Yanjie,Hu Guanghui,Jin Yong-Mei,Huang Kai,Guo Liping,Jiang Wenzhu,Du Xinglin 한국유전학회 2021 Genes & Genomics Vol.43 No.8

Background The Northeast Plain of China, which is an important region for the production of high grain quality rice in China. However, the grain quality of the rice produced varies across this region, even for the same cultivar. Objective In order to explore the meteorological factors that have the greatest infuence on quality and the transcriptional level diferences between diferent cultivars and diferent locations at grain flling stage. Methods We grew eight rice cultivars in three locations in Northeast China during two growing seasons (2017 and 2018). We recorded meteorological conditions, including air temperature, air temperature range, and photosynthetically active radiation (PAR) during the grain-flling stage of each cultivar, and analyzed the grain quality of those eight cultivars. Results Across all eight cultivars, meteorological factors had a stronger efect on eating quality than genotype, while genotype had a stronger efect on milling quality. Of the three environmental factors assessed, PAR was signifcantly correlated with the most grain quality traits. Using RNA-sequencing analysis, we identifed 573 environment-specifc DEGs (Diferentially Expressed Genes), and 119 genotype-specifc DEGs; 11 DEGs were responsive to genotype×environment interactions. These DEGs were involved in many key metabolic processes. Conclusion Our results indicated that interactions among environmental factors, especially PAR, afected rice quality in Northeast China. Further analyses of the DEGs identifed herein may provide useful information for future breeding programs aiming to develop high grain quality rice varieties suitable for cultivation across Northeast China.

Indium assisted hydride vapor phase epitaxy of GaN film

Guanghui Yu,Benliang Lei,Haohua Ye,Sheng Meng,Ming Qi,Aizhen Li,Jun Chen,Gerard Nouet,JPierre Ruterana 한양대학교 세라믹연구소 2006 Journal of Ceramic Processing Research Vol.7 No.2

In order to increase the migration length of adatoms in hydride vapor phase epitaxy (HVPE) of GaN films, indium was used as a surfactant in HVPE growth. For samples with indium, an increase of crystalline quality was confirmed by X-ray diffraction measurements, and an improvement of surface morphology was also observed. SIMS analysis showed that indium was incorporated in the as-grown GaN film, and indium related photoluminescence (PL) was also detected.

Comprehensive Utilisation of Biomass Tar for High Volumetric Capacitance Porous Carbon and Modified Bio-resin

Sui Guanghui,Cheng Yanyan,Chen Kai,Huang Zhifang,Luo MingHong 한국화학공학회 2024 Korean Journal of Chemical Engineering Vol.41 No.3

Biomass tar is a by-product generated during biomass gasifi cation. Because of the toxic and harmful nature of biomass tar, its treatment method has become the concern of environmental protection fi eld and related researchers. In this paper, biomass tar was separated into the heavy tar and the phenol-containing liquor after enrichment. Porous carbon (PCs) was prepared using the heavy tar by one-step carbonization activation. The results show that PC_3 has the highest specifi c surface area of 352 m 2 g −1 and mesoporosity ratio of 56.25%. The as-prepared electrode displayed an excellent electrochemical performance for portable super-capacitors, which is a volumetric capacitance of 349 F cm −3 . Assembled super-capacitors have an energy density of 21.65 Wh kg −1 at a power density of 123 W kg −1 . The bio-resins were modifi ed with the phenolcontaining liquor. The results showed that the thermal stability of modifi ed resins had been improved and the structure did not change signifi cantly. This research provides an environmentally friendly and comprehensive utilisation methods for the utilisation of biomass tar.

Computational fluid dynamics study on the anode feed solid polymer electrolyte water electrolysis

Shuguo Qu,Guanghui Chen,Jihai Duan,Weiwen Wang,Jianlong Li 한국화학공학회 2017 Korean Journal of Chemical Engineering Vol.34 No.6

A steady-state two-dimensional model for the anode feed solid polymer electrolyte water electrolysis (SPEWE) is proposed in this paper. Finite element procedure was employed to calculate the multicomponent transfer model coupled with fluid flow in flow channels and gas diffusion layers and electrochemical kinetics in catalyst reactive surface. The performance of the anode feed SPEWE predicted by this model was compared with the published experimental results and reasonable agreement was reached. The results show that oxygen mass fraction increases because of the water oxidation when water flows from the import to the export on the anode side. On the cathode side, hydrogen mass fraction varies little since hydrogen and water mix well. The flux of water across the electrolyte increased almost linearly with the increase of the applied current density. Since the ohmic overpotential loss increasing as the solid polymer electrolytes’ thickness increasing, the performance of the anode feed SPEWE with Nafion 112, 115, 117 decreases at the same applied current density.

Bayesian methods for dealing with missing data problems

Zhihua Ma,Guanghui Chen 한국통계학회 2018 Journal of the Korean Statistical Society Vol.47 No.3

Missing data, a common but challenging issue in most studies, may lead to biased and inefficient inferences if handled inappropriately. As a natural and powerful way for dealing with missing data, Bayesian approach has received much attention in the literature. This paper reviews the recent developments and applications of Bayesian methods for dealing with ignorable and non-ignorable missing data. We firstly introduce missing data mechanisms and Bayesian framework for dealing with missing data, and then introduce missing data models under ignorable and non-ignorable missing data circumstances based on the literature. After that, important issues of Bayesian inference, including prior construction, posterior computation, model comparison and sensitivity analysis, are discussed. Finally, several future issues that deserve further research are summarized and concluded.