Review on the research of contact parameters calibration of particle system

Xuewen Wang,Haozhou Ma,Bo Li,Tiejun Li,Rui Xia,Qingbao Bao 대한기계학회 2022 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.36 No.3

With the widespread application of the discrete element method, research on accurate simulation of particle systems has attracted significant attention. However, there is no accurate process for the parameter calibration of particle systems. Most calibrations use a direct measurement method or test-simulation combined calibration method. Both methods have their advantages and disadvantages. This study reviews the calibration of contact parameters of particle systems, introduces the main calibration methods of different contact parameters, and summarizes the advantages and disadvantages of two main measurement methods. For the parameter measurement of particle systems, the accurate representation of particle shape and the reasonable optimization of simulation time are still not perfect. Furthermore, the correction of parameters after calibration applied to subsequent simulation needs further discussion.

Removal of chloride ions from acidic solution with antimony oxides

Xuewen Wang,Yanping Du,Haoxiang Yang,Shenghui Tian,Qi Ge,Sheng Huang,Mingyu Wang 한국공업화학회 2021 Journal of Industrial and Engineering Chemistry Vol.93 No.-

This studyaims to investigate the removal of Cl- from acidic solutionwith antimony oxides. The effects of theadsorbenttype,reaction time,reaction temperature,Sb/Clmole ratio andacidityonadsorptionperformanceand the regeneration of loaded adsorbent were systematically studied. The results shows that Sb2O3 xH2Ohas the highest adsorption rate (97.64%) among Sb2O3 xH2O, Sb2O5 xH2O, Sb2O4 xH2O and Sb2O3 in thesolution containing 1.25 mol/L H2SO4under the condition of Sb/Cl mole ratio 3:1 and stirring for 2 h at roomtemperature, and the concentration of Cl- in the acid solution can be reduced to 280 mg/L. Then the residualSb in the adsorbed solution can be decreased from 48.21 mg/L to 16.09 mg/L by C-SbA which is made bySb2O5 xH2O. The C-SbA which has been used can be reused after calcining at 400 ℃ for 2 h. The loadedadsorbent was completely regenerated by adding it into NaOH or Na2CO3 solution whose pH is equal ormore than 9.5 according to S/L ratio 1:6 g/mL and was stirred for 0.5 h at room temperature. The Cl- in theregenerated solution was crystallized and precipitated in the form of NaCl without evaporation andconcentration according to the common ion effect of Na+, and the purity of NaCl was more than 99%.

LARGE TIME BEHAVIOR TO THE 2D MICROPOLAR BOUSSINESQ FLUIDS

XUEWEN WANG,KEKE LEI,PIGONG HAN 한국산업응용수학회 2022 Journal of the Korean Society for Industrial and A Vol.26 No.4

In this paper, we prove the global existence of classical solutions to the 2D in- compressible Boussinesq equations for the micropolar fluid. Furthermore, applying the Fourier splitting methods, we obtain the lager time decay properties.

SODIUM TANTALATE SPHERES PREPARED VIA AN ELECTROCHEMICAL PROCESS AND THEIR PHOTOELECTROCHEMICAL BEHAVIOR

XUEWEN WANG,LI ZHOU 성균관대학교(자연과학캠퍼스) 성균나노과학기술원 2013 NANO Vol.8 No.3

Photocatalytic activity can be improved through modified morphology and structure. Sodium tantalate (NaTaO3) as a semiconductor photocatalyst is extensively used for photocatalytic water splitting. A novel electrochemical route was developed for preparing NaTaO3 spheres. The method can easily and fast synthesize high pure phase NaTaO3 spheres at room temperature. The NaTaO3 sphere structure consists of a crystalline core and an amorphous shell. After a thermal treatment, the NaTaO3 spheres show an enhanced photoelectrochemical water splitting ability.

Mechanism of nitrogen-fluoride co-doped TiO2/bentonite composites removing tetracycline: A study in the co-doping ratio

Teng WANG,Zhaofu MENG,Xinxin WANG,Amjad ALI,Xuewen CAO,Lin LIU 대한환경공학회 2021 Environmental Engineering Research Vol.26 No.6

N-doped and N-F co-doped TiO2/bentonite composites were synthesized via the gel-sol method. The morphology, structure and surface charge of the composite before and after adsorption were used to determine the effect N/F doping ratio on TC removal. The results showed that, compared with undoped samples, the TC adsorption on N doped composites was reduced by 24.44% on average. N-F co-doping significantly increased the TC adsorption when the Ti-N-F molar ratio was 1:1: 0.01, reaching a maximum TC adsorption of 64.00 mmol·kg−1. The coverage of the N doped TiO2 increases as the N doping ratio increases; the specific surface area increased by 2.03 % on average, but the number of surface negative charges decreased by 36.24 % on average. FT-IR results confirmed that N doping reduced the number of -OH groups on the N-doped composites. Additionally, fluorination of N-F co-doped TiO2 and bentonite surfaces inhibits hydrogen bonding and π-π interactions between the TC and the composites. As the N doping ratio increased, the coverage of N-F co-doped TiO2 on the composite surface increased, resulting in the TC adsorption decrease with the increases N doping ratio.

Mechanism of nitrogen-fluoride co-doped TiO₂/bentonite composites removing tetracycline: A study in the co-doping ratio

Teng WANG,Zhaofu MENG,Xinxin WANG,Amjad ALI,Xuewen CAO,Lin LIU 대한환경공학회 2021 Environmental Engineering Research Vol.26 No.6

N-doped and N-F co-doped TiO₂/bentonite composites were synthesized via the gel-sol method. The morphology, structure and surface charge of the composite before and after adsorption were used to determine the effect N/F doping ratio on TC removal. The results showed that, compared with undoped samples, the TC adsorption on N doped composites was reduced by 24.44% on average. N-F co-doping significantly increased the TC adsorption when the Ti-N-F molar ratio was 1:1: 0.01, reaching a maximum TC adsorption of 64.00 mmol·kg<SUP>-1</SUP>. The coverage of the N doped TiO₂ increases as the N doping ratio increases; the specific surface area increased by 2.03 % on average, but the number of surface negative charges decreased by 36.24 % on average. FT-IR results confirmed that N doping reduced the number of -OH groups on the N-doped composites. Additionally, fluorination of N-F co-doped TiO₂ and bentonite surfaces inhibits hydrogen bonding and π-π interactions between the TC and the composites. As the N doping ratio increased, the coverage of N-F co-doped TiO₂ on the composite surface increased, resulting in the TC adsorption decrease with the increases N doping ratio.

Loss of KDM5B ameliorates pathological cardiac fibrosis and dysfunction by epigenetically enhancing ATF3 expression

Wang Bo,Tan Yong,Zhang Yunkai,Zhang Sheng,Duan Xuewen,Jiang Yuyu,Li Tong,Zhou Qingqing,Liu Xingguang,Zhan Zhenzhen 생화학분자생물학회 2022 Experimental and molecular medicine Vol.54 No.-

Excessive cardiac fibrosis is central to adverse cardiac remodeling and dysfunction leading to heart failure in many cardiac diseases. Histone methylation plays a crucial role in various pathophysiological events. However, the role of histone methylation modification enzymes in pathological cardiac fibrosis needs to be fully elucidated. Here, we identified lysine demethylase 5B (KDM5B), a histone H3K4me2/me3 demethylase, as a key epigenetic mediator of pathological cardiac fibrosis. KDM5B expression was upregulated in cardiac fibroblasts and myocardial tissues in response to pathological stress. KDM5B deficiency markedly ameliorated cardiac fibrosis, improved cardiac function, and prevented adverse cardiac remodeling following myocardial infarction (MI) or pressure overload. KDM5B knockout or inhibitor treatment constrained the transition of cardiac fibroblasts to profibrogenic myofibroblasts and suppressed fibrotic responses. KDM5B deficiency also facilitated the transformation of cardiac fibroblasts to endothelial-like cells and promoted angiogenesis in response to myocardial injury. Mechanistically, KDM5B bound to the promoter of activating transcription factor 3 (Atf3), an antifibrotic regulator of cardiac fibrosis, and inhibited ATF3 expression by demethylating the activated H3K4me2/3 modification, leading to the enhanced activation of TGF-β signaling and excessive expression of profibrotic genes. Our study indicates that KDM5B drives pathological cardiac fibrosis and represents a candidate target for intervention in cardiac dysfunction and heart failure.

A drug delivery system constructed by a fusion peptide capturing exosomes targets to titanium implants accurately resulting the enhancement of osseointegration peri-implant

Li Xuewen,Liu Zihao,Xu Shendan,Ma Xinying,Zhao Zhezhe,Hu Han,Deng Jiayin,Peng Cheng,Wang Yonglan,Ma Shiqing 한국생체재료학회 2023 생체재료학회지 Vol.27 No.00

Exosomes derived from bone marrow mesenchymal stem cells (BMSC-exos) have been shown triggering osteogenic differentiation and mineralization of MSCs, but exosomes administered via bolus injections are rapidly sequestered and cleared. Therefore, we considered the implant as a new organ of patient’s body and expected to find a method to treat implant with BMSC-exos in vivo directly.A fusion peptide (PEP), as a drug delivery system (DDS) which contained a titanium-binding peptide (TBP) possessing the ability to selectively bind to the titanium surface and another peptide CP05 being able to capture exosomes expertly, is constructed to modify the titanium surface.Both in vitro and in vivo experiments prove PEP retains the ability to bind titanium and exosome simultaneously, and the DDS gain the ability to target exosomes to titanium implants surface following enhancing osseointegration post-implantation. Moreover, the DDS constructed by exosomes of diverse origins shows the similar combination rate and efficiency of therapy.This drug delivery system demonstrates the concept that EXO-PEP system can offer an accurate and efficient therapy for treating implants with long-term effect.

Effect of Transformation Temperature on the Ferrite–Bainite Microstructures, Mechanical Properties and the Deformation Behavior in a Hot-Rolled Dual Phase Steel

Bo Jiang,Xuewen Hu,Leyu Zhou,Haibo Wang,Yazheng Liu,Fugang Gou 대한금속·재료학회 2021 METALS AND MATERIALS International Vol.27 No.2

The ferrite–bainite microstructures and mechanical properties in a hot-rolled dual phase steel with different transformationtemperatures were investigated in this paper. The deformation behavior of bainite and ferrite was analyzed by using in situscanning electron microscope. The results showed that the ferrite and bainite can be refined and the volume fraction of bainitecan be slightly increased by 5% by decreasing the ferrite transformation temperature from 690 to 635 °C and increasing thebainite transformation temperature from 400 to 450 °C. The strengthening mechanism was dislocation difference in polygonaland acicular ferrite and then the grain size difference of ferrite. The hole expansion ratio increased from 52.9 to 83.7% withthe ferrite transformation temperature decreasing. The cracks or voids were smaller in size and also the number in steel withthe lower ferrite transformation temperature after expanding. The microstructure separation along the boundary betweenbainite and ferrite and the slip band in the ferrite appeared at the non-uniform deformation stage. However, fewer appearedin the microstructure of steel with lower ferrite transformation temperature. Cooperative deformation of ferrite and bainiteand finer microstructure in steel with lower ferrite transformation temperature were the mechanisms why the cracks couldnot easily nucleated and propagated, respectively. Thus this was also why there was a better hole expansion ratio.

Microstructural Characterization and Softening Mechanism of Ultra-Low Carbon Steel and the Control Strategy in Compact Strip Production Process

Bo Jiang,Xuewen Hu,Guoning He,Huan Peng,Haibo Wang,Yazheng Liu 대한금속·재료학회 2020 METALS AND MATERIALS International Vol.26 No.9

In this paper, the microstructures and properties of hot rolled ultra-low carbon steel sheet produced by different compact stripproduction (CSP) processes were investigated. The softening mechanism was also discussed and the control strategy wasproposed in order to obtain optimum properties. Result showed that the average ferrite grain sizes of austenite rolling sheetand multiphase rolling sheet were 31.0 μm and 74.6 μm, respectively. The sheet after austenite rolling had a slightly higheryield and tensile strength while had a 6.3% higher elongation than that of the sheet after multiphase rolling. The higher dislocationin the sheet after multiphase rolling increased the strength while decreased the elongation. The softening mechanismof the sheet after multiphase rolling was the coarsening of ferrite grain. The combined role of {001} and {111} orientationresulted in a slight increase of the r and ̄rvalue in the sheet after multiphase rolling. It was a wise choice to conduct rollingat the Ac1temperature in CSP process to increase the grain size and decrease the dislocation density. Then, the strength ofthe sheets could be further reduced and the elongation could also be improved.