Microstructure, Mechanical Properties and Fracture Behavior of Magnesium/Steel Bimetal Using Compound Casting Assisted with Hot-Dip Aluminizing

Wenming Jiang,Haixiao Jiang,Guangyu Li,Feng Guan,Junwen Zhu,Zitian Fan 대한금속·재료학회 2021 METALS AND MATERIALS International Vol.27 No.8

In this work, microstructure, mechanical properties and fracture behavior of the magnesium/steel bimetal using compoundcasting assisted with hot-dip aluminizing were investigated, and the interface bonding mechanism of the magnesium/steelbimetal were also analyzed. The results indicate that the magnesium/steel bimetal obtained without hot-dip aluminizing hadlarger gaps through the whole interface without reaction layers between magnesium and steel, leading to a poor mechanicalbonding. After the steel substrate was hot-dip aluminized, an intermetallic layer along with an Al topcoat layer wereformed on the surface of the steel substrate, and the intermetallic layer was constituted by Fe2Al5,τ10-Al9Fe4Si3, FeAl3andτ6-Al4.5FeSi phases. In the case of the magnesium/steel bimetal obtained with hot-dip aluminizing, a compact and uniforminterface layer with an average thickness of about 17 μm that consisted of Fe2Al5,τ10-Al9Fe4Si3, FeAl3and Al12Mg17intermetalliccompounds was formed between the magnesium and the steel, obtaining a superior metallurgical bonding. The interfacelayer had much higher nano-hardnesses compared to the magnesium and steel matrixes, and its average nano-hardness wasup to 11.1 GPa, while there were respectively 1.1 and 4.2 GPa for the magnesium and steel matrixes. The shear strength ofthe magnesium/steel bimetal with hot-dip aluminizing reached to 23.3 MPa, which increased by 8.59 times than that of thecomposites without hot-dip aluminizing. The fracture of the magnesium/steel bimetal with hot-dip aluminizing representeda brittle fracture nature, initiating from the interface layer.

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.

Numerical study on failure behavior of open-hole composite laminates based on LaRC criterion and extended finite element method

Decheng Liu,Dongfeng Cao,Haixiao Hu,Yucheng Zhong,Shuxin Li 대한기계학회 2021 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.35 No.3

A new numerical model combining LaRC failure criterion and extended finite element method (XFEM) is created to describe the failure behavior in fiber-reinforced polymer (FRP) composites. In this model, the onset of intralaminar damages are predicted based on the LaRC failure criterion, and the crack propagation and stiffness degradation are described explicitly by the XFEM. The user subroutine UDMGINI of ABAQUS defines the initial damage criterion and a mixed-mode, energy-based fracture criterion is employed to describe the crack onset and propagation in the enriched region of XFEM. The proposed model is used to investigate the failure behavior of two sets of open-hole laminates under tension. It is demonstrated that the proposed numerical method can predict the experimental data well.

Copper-induced injectable hydrogel with nitric oxide for enhanced immunotherapy by amplifying immunogenic cell death and regulating cancer associated fibroblasts

Shuilin Shen,Zimeng Zhang,Haixiao Huang,Jing Yang,Xinyue Tao,Zhengjie Meng,Hao Ren,Xueming Li 한국생체재료학회 2023 생체재료학회지 Vol.27 No.00

Background Immunogenic cell death (ICD) induced by different cancer treatments has been widely evaluated to recruit immune cells and trigger the specific antitumor immunity. However, cancer associated fibroblasts (CAFs) can hinder the invasion of immune cells and polarize the recruited monocytes to M2-type macrophages, which greatly restrict the efficacy of immunotherapy (IT). Methods In this study, an injectable hydrogel induced by copper (Cu) has been designed to contain antibody of PD-L1 and nitric oxide (NO) donor. The therapeutic efficacy of hydrogel was studied in 4T1 cells and CAFs in vitro and 4T1 tumor-bearing mice in vivo. The immune effects on cytotoxic T lymphocytes, dendritic cells (DCs) and macrophages were analyzed by flow cytometry. Enzyme-linked immunosorbent assay, immunofluorescence and transcriptome analyses were also performed to evaluate the underlying mechanism. Results Due to the absorbance of Cu with the near-infrared laser irradiation, the injectable hydrogel exhibits persistent photothermal effect to kill cancer cells. In addition, the Cu of hydrogel shows the Fenton-like reaction to produce reactive oxygen species as chemodynamic therapy, thereby enhancing cancer treatment and amplifying ICD. More interestingly, we have found that the released NO can significantly increase depletion of CAFs and reduce the proportion of M2-type macrophages in vitro. Furthermore, due to the amplify of ICD, injectable hydrogel can effectively increase the infiltration of immune cells and reverse the immunosuppressive tumor microenvironment (TME) by regulating CAFs to enhance the therapeutic efficacy of anti-PD-L1 in vivo. Conclusions The ion induced self-assembled hydrogel with NO could enhance immunotherapy via amplifying ICD and regulating CAFs. It provides a novel strategy to provoke a robust antitumor immune response for clinical cancer immunotherapy.

A GPU-Accelerated Hydrodynamic Model for Urban Rainstorm Inundation Simulation: A Case Study in China

Hao Han,Jingming Hou,Zongxue Xu,Haixiao Jing,Jiahui Gong,Depeng Zuo,Bingyao Li,Shaoxiong Yang,Yongde Kang,Run Wang 대한토목학회 2022 KSCE JOURNAL OF CIVIL ENGINEERING Vol.26 No.3

Frequent urban rainstorm inundations can cause serious damages to human life and social economy. Reliable simulation of urban rainstorm inundation is an effective approach for performing flood risk analysis to reduce losses. In this work, a full 2D high-performance hydrodynamic model for urban rainstorm inundation simulation based on Graphic Processing Unit (GPU) was developed. The idealized V-shape catchment and sponge city district of Fengxi New City were selected as the study areas to assess performance of the model. The model was validated against analytical benchmark results of the idealized V-catchment test which show good agreement between the modelled flow and analytical solutions. The model was then applied to simulate actual urban rainstorm inundation process under measured rainfall. The results indicated that the model can be applied to high-resolution urban region simulations. Specifically, the validation results indicated that the proposed model had a good performance, with an accepted error of less than 15%. When applied to compute the Fengxi New city under design rainstorms with different annual return periods of 1, 5, 10, 20, 50, and 100 years, it was found that the model effectively evaluated the temporal and spatial variation process of urban inundation, and quantitatively investigated flood risks according to the water depth change. The model has been substantially accelerated on GPU to quickly predict urbaninundation. The accuracy and rapid simulation speed of the model were verified based on the actual study area. Therefore, the proposed model can help to predict the dynamic processes of urban flood inundation and thus reduce flood inundation disasters. This is essential for future optimal sponge urban construction planning in China.

Rheinic acid ameliorates radiation‑induced acute enteritis in rats through PPAR‑γ/NF‑κB

Haixia Sha,Yu Gu,Weixing Shen,Li Zhang,Fei Qian,Yudong Zhao,Haixiao Li,Ting Zhang,Weimin Lu 한국유전학회 2019 Genes & Genomics Vol.41 No.8

Background Acute radiation enteritis (ARE), a common complication of intestinal caused by abdominal and pelvic radiation therapy. Rheinic acid is a major active ingredient derived from Rhubarb. Rhubarb could suppress inflammation, tumor, fibrosis oxidative damage. However, RA as the main active component and extract monomer of Rhubarb, the pharmacological activity and the underlying molecular mechanism on various diseases has not yet been revealed. Objective To determine the potential role of rheinic acid (RA) in ameliorating inflammation of rats with acute radiation enteritis (ARE), and explore the underlying mechanism. Methods ARE rat model was established by irradiated with single-dose 10 Gy X-rays at a rate of 0.62 Gy/min to the abdomen. The rats were executed after orally administered with Rheinic acid 7 days and used in the subsequent experiments. Body weight, fecal characteristics and bloody of rats were used to assess the disease activity index. Histological analysis of the jejunum and colon were evaluated using H&E staining. The pro-inflammatory cytokines levels were measured by immunohistochemistry and ELISA. The levels of nitric oxide (NO), malondialdehyde (MDA), superoxide dismutase (SOD) and glutathione (GSH) were also determined. The mRNA and protein expression were examined by real-time polymerase chain reaction (qRT-PCR) and western blot, respectively. Results Rheinic acid promoted intestinal functional recovery, and ameliorated intestinal damage and bloody stool in ARE rats. Rheinic acid strongly decreased the levels of tumor necrosis factor-α, interleukin-1, interleukin-6, NO, and MDA, whereas increased levels of anti-oxidants, SOD and GSH. Moreover, the expression of apoptosis-related proteins, cleaved caspase-3 and cleaved poly (ADP-ribose) polymerase (PARP), were decreased with RA treatment. Further study indicated that PPAR-γ was activated and thereby NF-κB and p38 MAPK signaling pathway were suppressed after rheinic acid treatment. Conclusion Rheinic acid could ameliorate acute radiation enteritis and the underlying molecular mechanism is, at least partially, through PPAR-γ/NF-κB and p38 MAPK/JNK pathways.