Tool Wear in Longitudinal-Torsional Ultrasonic Vibration Assisted Drilling of CFRP/Ti Stacks and Its Influence on Drilling Quality

Chunhao Wang,Pengnan Li,Shujian Li,Xinyi Qiu,Changping Li,Qingquan Jiang,Qiulin Niu,Tae Jo Ko 한국정밀공학회 2024 International Journal of Precision Engineering and Vol.25 No.1

Longitudinal-torsional ultrasonic vibration assisted drilling (LTUVD) has received extensive attention as a new machining technology in recent years. Especially for the stacks structure similar to carbon fiber reinforced polymer/titanium alloy material (CFRP/Ti6Al4V), it has more significant machining advantages. However, the effect mechanism of longitudinal-torsional ultrasonic vibration (LTUV) on tool wear, the tool wear condition in LTUVD machining and its influence on machining quality are not clear. In this work, the effect of LTUV on the tool wear of CFRP/Ti stacks was analyzed, and the tool wear of CFRP/Ti stacks and its effect on the entrance, interface and hole wall were investigated by drilling experiments under LTUVD condition. The analysis demonstrated that LTUVD can reduce tool wear by reducing the force and temperature during CFRP/Ti stacks drilling. The typical characteristics of LTUVD drill wear were the reduction of the flank face width, the adhesion of Ti to the tool, the blunting and the fracture of the cutting edge. The worn tool shows different wear characteristics in different parts. Spindle speed is one of the key factors that affect the wear rate of the typical parts, such as chisel edge, outer edge corner and main cutting edge. The mean damage factor of the entrance and interface of the 17–20 holes drilled by LTUVD were 11.5% and 8.7% higher than those of the 1–4 holes respectively. As the tool wear intensifies, the hole wall of CFRP produced more pits and the flatness decreased. The hole wall roughness increased by 30.9% when the 17–20 holes were drilled compared with the 1–4 holes.

American ginseng attenuates azoxymethane/dextran sodium sulfate-induced colon carcinogenesis in mice

Chunhao Yu,Xiao-Dong Wen,Zhiyu Zhang,Chun-Feng Zhang,Xiao-Hui Wu,Adiba Martin,Wei Du,Tong-Chuan He,Chong-Zhi Wang,Chun-Su Yuan 고려인삼학회 2015 Journal of Ginseng Research Vol.39 No.1

Background: Colorectal cancer is a leading cause of cancer-related death, and inflammatory bowel diseaseis a risk factor for this malignancy. We previously reported colon cancer chemoprevention potentialusing American ginseng (AG) in a xenograft mice model. However, the nude mouse model is not a gutspecificcolon carcinogenesis animal model. Methods: In this study, an experimental colitis and colitis-associated colorectal carcinogenesis mousemodel, chemically induced by azoxymethane/dextran sodium sulfate (DSS) was established and theeffects of oral AG were evaluated. The contents of representative ginseng saponins in the extract weredetermined. Results: AG significantly reduced experimental colitis measured by the disease activity index scores. Thissuppression of the experimental colitis was not only evident during DSS treatment, but also very obviousafter the cessation of DSS, suggesting that the ginseng significantly promoted recovery from the colitis. Consistent with the anti-inflammation data, we showed that ginseng very significantly attenuatedazoxymethane/DSS-induced colon carcinogenesis by reducing the colon tumor number and tumor load. The ginseng also effectively suppressed DSS-induced proinflammatory cytokines activation using anenzyme-linked immunosorbent assay array, in which 12 proinflammatory cytokine levels were assessed,and this effect was supported subsequently by real-time polymerase chain reaction data. Conclusion: AG, as a candidate of botanical-based colon cancer chemoprevention, should be furtherinvestigated for its potential clinical utility.

American ginseng significantly reduced the progression of high-fatdiet-enhanced colon carcinogenesis in ApcMin/þmice

Chunhao Yu,Xiao-Dong Wen,Zhiyu Zhang,Chun-Feng Zhang,Xiaohui Wu,Xin He,Yang Liao,Ningning Wu,Chong-Zhi Wang,Wei Du,Tong-Chuan He,Chun-Su Yuan 고려인삼학회 2015 Journal of Ginseng Research Vol.39 No.3

Background: Colorectal cancer (CRC) is a leading cause of death worldwide. Chronic gut inflammation is recognized as a risk factor for tumor development, including CRC. American ginseng is a very commonly used ginseng species in the West. Methods: A genetically engineered ApcMin/þ mouse model was used in this study. We analyzed the saponin composition of American ginseng used in this project, and evaluated its effects on the progression of high-fat-diet-enhanced CRC carcinogenesis. Results: After oral ginseng administration (10e20 mg/kg/d for up to 32 wk), experimental data showed that, compared with the untreated mice, ginseng very significantly reduced tumor initiation and progression in both the small intestine (including the proximal end, middle end, and distal end) and the colon (all p < 0.01). This tumor number reduction was more obvious in those mice treated with a low dose of ginseng. The tumor multiplicity data were supported by body weight changes and gut tissue histology examinations. In addition, quantitative real-time polymerase chain reaction analysis showed that compared with the untreated group, ginseng very significantly reduced the gene expression of inflammatory cytokines, including interleukin-1a (IL-1a), IL-1b, IL-6, tumor necrosis factor-a, granulocyte-colony stimulating factor, and granulocyte-macrophage colony-stimulating factor in both the small intestine and the colon (all p < 0.01). Conclusion: Further studies are needed to link our observed effects to the actions of the gut microbiome in converting the parent ginsenosides to bioactive ginseng metabolites. Our data suggest that American ginseng may have potential value in CRC chemoprevention.

Current progress in remediation of chlorinated volatile organic compounds: A review

Chunhao Dai,Yaoyu Zhou,Hui Peng,Shaojian Huang,Pufeng Qin,Jiachao Zhang,Yuan Yang,Lin Luo,Xiaoshan Zhang 한국공업화학회 2018 Journal of Industrial and Engineering Chemistry Vol.62 No.-

Chlorinated volatile organic compounds (Cl-VOCs) contamination has been recognized as one of the major problem in worldwide due to natural and anthropogenic activities. Recently, several treatment technologies (e.g., adsorption for broader concentration Cl-VOCs, catalytic combustion for high concentration (>500 ppm), advanced oxidation, electrochemical method, metal method and photocatalytic method for low concentration (<500 ppm)) have been applied for Cl-VOCs elimination. In this review, an extensive list of every method from literatures is compiled, and their capacities under various conditions are presented. However, there is still need to find out the practical technologies on commercial scale, leading to improvement of environmental pollution control.

American ginseng attenuates azoxymethane/dextran sodium sulfate-induced colon carcinogenesis in mice

Chunhao Yu,Xiao-Dong Wen,Zhiyu Zhang,Chun-Feng Zhang,Xiao-Hui Wu,Adiba Martin,Wei Du,Tong-Chuan He,Chong-Zhi Wang,Chun-Su Yuan 고려인삼학회 2015 Journal of Ginseng Research Vol.39 No.3

Background: Colorectal cancer is a leading cause of cancer-related death, and inflammatory bowel disease is a risk factor for this malignancy. We previously reported colon cancer chemoprevention potential using American ginseng (AG) in a xenograft mice model. However, the nude mouse model is not a gutspecific colon carcinogenesis animal model. Methods: In this study, an experimental colitis and colitis-associated colorectal carcinogenesis mouse model, chemically induced by azoxymethane/dextran sodium sulfate (DSS) was established and the effects of oral AG were evaluated. The contents of representative ginseng saponins in the extract were determined. Results: AG significantly reduced experimental colitis measured by the disease activity index scores. This suppression of the experimental colitis was not only evident during DSS treatment, but also very obvious after the cessation of DSS, suggesting that the ginseng significantly promoted recovery from the colitis. Consistent with the anti-inflammation data, we showed that ginseng very significantly attenuated azoxymethane/DSS-induced colon carcinogenesis by reducing the colon tumor number and tumor load. The ginseng also effectively suppressed DSS-induced proinflammatory cytokines activation using an enzyme-linked immunosorbent assay array, in which 12 proinflammatory cytokine levels were assessed, and this effect was supported subsequently by real-time polymerase chain reaction data. Conclusion: AG, as a candidate of botanical-based colon cancer chemoprevention, should be further investigated for its potential clinical utility.

American ginseng attenuates azoxymethane/dextran sodium sulfate-induced colon carcinogenesis in mice

Yu, Chunhao,Wen, Xiao-Dong,Zhang, Zhiyu,Zhang, Chun-Feng,Wu, Xiao-Hui,Martin, Adiba,Du, Wei,He, Tong-Chuan,Wang, Chong-Zhi,Yuan, Chun-Su The Korean Society of Ginseng 2015 Journal of Ginseng Research Vol.39 No.1

Background: Colorectal cancer is a leading cause of cancer-related death, and inflammatory bowel disease is a risk factor for this malignancy. We previously reported colon cancer chemoprevention potential using American ginseng (AG) in a xenograft mice model. However, the nude mouse model is not a gut-specific colon carcinogenesis animal model. Methods: In this study, an experimental colitis and colitis-associated colorectal carcinogenesis mouse model, chemically induced by azoxymethane/dextran sodium sulfate (DSS) was established and the effects of oral AG were evaluated. The contents of representative ginseng saponins in the extract were determined. Results: AG significantly reduced experimental colitis measured by the disease activity index scores. This suppression of the experimental colitis was not only evident during DSS treatment, but also very obvious after the cessation of DSS, suggesting that the ginseng significantly promoted recovery from the colitis. Consistent with the anti-inflammation data, we showed that ginseng very significantly attenuated azoxymethane/DSS-induced colon carcinogenesis by reducing the colon tumor number and tumor load. The ginseng also effectively suppressed DSS-induced proinflammatory cytokines activation using an enzyme-linked immunosorbent assay array, in which 12 proinflammatory cytokine levels were assessed, and this effect was supported subsequently by real-time polymerase chain reaction data. Conclusion: AG, as a candidate of botanical-based colon cancer chemoprevention, should be further investigated for its potential clinical utility.

American ginseng significantly reduced the progression of high-fat-diet-enhanced colon carcinogenesis in Apc^Min/+ mice

Yu, Chunhao,Wen, Xiao-Dong,Zhang, Zhiyu,Zhang, Chun-Feng,Wu, Xiaohui,He, Xin,Liao, Yang,Wu, Ningning,Wang, Chong-Zhi,Du, Wei,He, Tong-Chuan,Yuan, Chun-Su The Korean Society of Ginseng 2015 Journal of Ginseng Research Vol.39 No.3

Background: Colorectal cancer (CRC) is a leading cause of death worldwide. Chronic gut inflammation is recognized as a risk factor for tumor development, including CRC. American ginseng is a very commonly used ginseng species in the West. Methods: A genetically engineered $Apc^{Min/+}$ mouse model was used in this study. We analyzed the saponin composition of American ginseng used in this project, and evaluated its effects on the progression of high-fat-diet-enhanced CRC carcinogenesis. Results: After oral ginseng administration (10-20 mg/kg/d for up to 32 wk), experimental data showed that, compared with the untreated mice, ginseng very significantly reduced tumor initiation and progression in both the small intestine (including the proximal end, middle end, and distal end) and the colon (all p < 0.01). This tumor number reduction was more obvious in those mice treated with a low dose of ginseng. The tumor multiplicity data were supported by body weight changes and gut tissue histology examinations. In addition, quantitative real-time polymerase chain reaction analysis showed that compared with the untreated group, ginseng very significantly reduced the gene expression of inflammatory cytokines, including interleukin-$1{\alpha}$ (IL-$1{\alpha}$), IL-$1{\beta}$, IL-6, tumor necrosis factor-${\alpha}$, granulocyte-colony stimulating factor, and granulocyte-macrophage colony-stimulating factor in both the small intestine and the colon (all p < 0.01). Conclusion: Further studies are needed to link our observed effects to the actions of the gut microbiome in converting the parent ginsenosides to bioactive ginseng metabolites. Our data suggest that American ginseng may have potential value in CRC chemoprevention.

Bacitracin Inhibits the Migration of U87-MG Glioma Cells via Interferences of the Integrin Outside-in Signaling Pathway

Li, Songyuan,Li, Chunhao,Ryu, Hyang-Hwa,Lim, Sa-Hoe,Jang, Woo-Youl,Jung, Shin The Korean Neurosurgical Society 2016 Journal of Korean neurosurgical society Vol.59 No.2

Objective : Protein disulfide isomerase (PDI) acts as a chaperone on the cell surface, and it has been reported that PDI is associated with the tumor cell migration and invasion. The aims of this study are to investigate the anti-migration effect of bacitracin, which is an inhibitor of PDI, and the associated factor in this process. Methods : U87-MG glioma cells were treated with bacitracin in 1.25, 2.5, 3.75, and 5.0 mM concentrations. Western blot with caspase-3 was applied to evaluate the cytotoxicity of bacitracin. Adhesion, morphology, migration assays, and organotypic brain-slice culture were performed to evaluate the effect of bacitracin to the tumor cell. Western blot, PCR, and gelatin zymography were performed to investigate the associated factors. Thirty glioma tissues were collected following immunohistochemistry and Western blot. Results : Bacitracin showed a cytotoxicity in 3rd (p<0.05) and 4th (p<0.001) days, in 5.0 Mm concentration. The cell adhesion significantly decreased and the cells became a round shape after treated with bacitracin. The migration ability, the expression of phosphorylated focal adhesion kinase (p-FAK) and matrix metalloproteinase-2 (MMP-2) decreased in a bacitracin dose- and time-dependent manner. The U87-MG cells exhibited low-invasiveness in the 2.5 mM, compared with the untreated in organotypic brain-slice culture. PDI was expressed in the tumor margin, and significantly increased with histological glioma grades (p<0.001). Conclusion : Bacitracin, as a functional inhibitor of PDI, decreased the phosphorylated FAK and the secreted MMP-2, which are the downstream of integrin and play a major role in cell migration and invasion, might become one of the feasible therapeutic strategies for glioblastoma.