Improvements of the CMFD acceleration capability of OpenMOC

Wenbin Wu,Guillaume Giudicelli,Kord Smith,Benoit Forget,Dong Yao,Yingrui Yu,Qi Luo 한국원자력학회 2020 Nuclear Engineering and Technology Vol.52 No.10

Due to its computational efficiency and geometrical flexibility, the Method of Characteristics (MOC) has been widely used for light water reactor lattice physics analysis. Usually acceleration methods are necessary for MOC to achieve acceptable convergence on practical reactor physics problems. Among them, Coarse Mesh Finite Difference (CMFD) is very popular and can drastically reduce the number of transport iterations. In OpenMOC, CMFD acceleration was implemented but had the limitation of supporting only a uniform CMFD mesh, which would often lead to splitting MOC source regions, thus creating an unnecessary increase in computation and memory use. In this study, CMFD acceleration with a non-uniform Cartesian mesh is implemented into OpenMOC. We also propose a quadratic fit based CMFD prolongation method in the axial direction to further improve the acceleration when multiple MOC source regions are contained in one CMFD coarse mesh. Numerical results are presented to demonstrate the improvement of the CMFD acceleration capability in OpenMOC in terms of both efficiency and stability.

Edge Effect Investigation of DP980 Steel Sheet in Multiple Laser Scanning Process

Yajing Zhang,Wenbin Dong,Yinhu Qiao,Chunyu Zhang 한국정밀공학회 2019 International Journal of Precision Engineering and Vol.20 No.3

Due to free spring back, laser forming is an effective non-contact forming technique for hard forming materials. A desired shape is obtained by residual plastic strain which is induced by thermal stresses depending on multiple laser scanning. In this study, the combination of experimental and numerical analysis is employed to investigate the temperature distribution and bending angle of the dual phase (DP980) high strength steel sheet. The edge effect of six cases of laser scanning process involving 1, 2, 3, 4, 5 and 10-time laser scanning are investigated by analyzing their bending angle relative variations and transverse plastic strains. It is found that the edge effect at the middle part of laser scanning line reduces with the increasing number of laser scanning cycles. It is attributed to the fact that the relative variation of the residual plastic strain reduces with the increase of laser scanning cycles. To efficiently reduce the edge effect of DP980 steel sheet, a locally repeated scanning strategy is proposed. The numerical simulation results indicate that the edge effect reduces significantly in the 10-time laser scanning process and the average bending angle simultaneously increases around 20% under the new laser scanning strategy.

Thermospheric Wind Observation and Simulation during the Nov 4, 2021 Geomagnetic Storm Event

Qian Wu,Dong Lin,Wenbin Wang,William Ward 한국우주과학회 2022 Journal of Astronomy and Space Sciences Vol.39 No.3

Thermospheric wind observations from high to mid latitudes are compared with the newly developed Multiscale Atmosphere Geospace Environment (MAGE) model for the Nov 3–4 geomagnetic storm. The observation and simulation comparison shows a very good agreement and is better at high latitudes in general. We were able to identify a thermospheric poleward wind reduction possibly linked to a northward turning of the Interplanetary Magnetic Field (IMF) at ~22 UT on Nov 3 and an enhancement of the poleward wind to a southward turning near 10 UT on Nov 4 at high latitudes. An IMF southward turning may have led to an enhancement of equatorward winds at Boulder, Colorado near midnight. Simultaneous occurrence of aurora may be associated with an IMF By turning negative. The MAGE model wind simulations are consistent with observations in these cases. The results show the model can be a very useful tool to further study the magnetosphere and ionosphere coupling on short time scales.

Thermospheric Wind Observation and Simulation during the Nov 4, 2021 Geomagnetic Storm Event

Wu, Qian,Lin, Dong,Wang, Wenbin,Ward, William The Korean Space Science Society 2022 Journal of astronomy and space sciences Vol.39 No.3

Thermospheric wind observations from high to mid latitudes are compared with the newly developed Multiscale Atmosphere Geospace Environment (MAGE) model for the Nov 3-4 geomagnetic storm. The observation and simulation comparison shows a very good agreement and is better at high latitudes in general. We were able to identify a thermospheric poleward wind reduction possibly linked to a northward turning of the Interplanetary Magnetic Field (IMF) at ~22 UT on Nov 3 and an enhancement of the poleward wind to a southward turning near 10 UT on Nov 4 at high latitudes. An IMF southward turning may have led to an enhancement of equatorward winds at Boulder, Colorado near midnight. Simultaneous occurrence of aurora may be associated with an IMF By turning negative. The MAGE model wind simulations are consistent with observations in these cases. The results show the model can be a very useful tool to further study the magnetosphere and ionosphere coupling on short time scales.

Management of COVID-19-related immune thrombocytopenia by rhTPO

Xuzhao Zhang,Min Li,Tao Chen,Dong Lv,Pengfei Xia,Wenbin Qian 대한혈액학회 2021 Blood Research Vol.56 No.3

.

Functional insights from targeted imaging BACE1: the first near-infrared fluorescent probe for Alzheimer’s disease diagnosis

Bi Anyao,Wu Junyong,Huang Shuai,Li Yongjiang,Zheng Fan,Ding Jipeng,Dong Jie,Xiang Daxiong,Zeng Wenbin 한국생체재료학회 2023 생체재료학회지 Vol.27 No.00

β-Secretase (BACE1) is the vital enzyme in the pathogenic processes of Alzheimer's disease (AD). However, the development of a powerful tool with sensitivity for BACE1 determination in vivo is a challenge.A novel NIR fluorescent probe HBAE was synthetized from 2-hydroxy-3-methylbenzaldehyde and 2-amino-benzenethiol by 5 steps. The fluorescence mechanism in the ESIPT systems of HBAE probe was insighted with time-dependent density functional theory (TD-DFT) at the TDPBE0 level with the def2-TZVP approach. The corresponding docking between HBAE and BACE1 (PDB: 5I3Y) was performed through the ducking method by DOCK6.8. Then the BBB permeability of HBAE is verified by transwell orifice plate. 22-month-old male AD-model (5XFAD) mice and age-matched wild-type mice were employed to observe the brain kinetics by intravenous injection. Finally, Immunohistochemistry was performed on the AD brain section to reveal the levels of BACE1 in hippocampus and cortex areas and other regions in AD mice through the brain tissue slices by HBAE.The NIR fluorescent probe HBAE was successfully applied in imaging BACE1 in AD model mice. The capability of HBAE in reflecting different level of BACE1 was performed by the specific imaging of the hippocampus region.We reported the first ESIPT near-infrared fluorescence probe HBAE for monitoring endogenous BACE1 in the AD live model mice, thus offering a versatile chemical tool for visualizing in the pathological processes of AD live brains. Remarkably, high resolution images showed the localization of red fluorescence stains in hippocampus of the AD brain. This study provides a promising way for functional insights from protein BACE1 in vivo.

Experimental and Modeling Studies on the Sorption Breakthrough Behaviors of Butanol from Aqueous Solution in a Fixed-bed of KA-I Resin

Xiaoqing Lin,Renjie Li,Qingshi Wen,Jinglan Wu,Jiansheng Fan,Xiaohong Jin,Wenbin Qian,Dong Liu,Xiaochun Chen,Yong Chen,Jingjing Xie,Jianxin Bai,Han-Jie Ying 한국생물공학회 2013 Biotechnology and Bioprocess Engineering Vol.18 No.2

Removal of biobutanol from acetone-butanolethanol (ABE) fermentation broth can be achieved by fixed-bed sorption by means of KA-I resin, and the relevant breakthrough curves would provide much valuable information to help design a continuous fixed-bed sorption process in field application. In the present study, the effects of several important design parameters, i.e., initial butanol concentration (Cf: 3.0 ~ 30.0 g/L), inlet flow rate (Qf: 0.5~ 5.5 mL/min) and adsorbent bed height (Z: 4.2 ~ 18.0 cm),on the adsorption breakthrough curves of KA-I resin in a fixed-bed column were investigated. It was found that the amount of adsorbed butanol at breakthrough point was increased with an increase in the value of Cf and Z; and with decrease in the value of Qf. However, the maximum sorption capacities of butanol at saturated point were basically unchanged. Three well-established fixed-bed adsorption models, namely Thomas, Yoon-Nelson and Adams-Bohart,were applied to predict the breakthrough curves and to determine the characteristic parameters of fixed-bed column,which are the basis for the process design at a real scale. Good agreement between the theoretical breakthrough curves and the experimental result were observed using Thomas and Yoon-Nelson models.