Microstructure and tribological properties of ion beam‑modified GO‑reinforced copper matrix composites

Zi‑liang Liu,Yong Li,Xiao Guo,Jun‑jie Tao,Ji‑ning Huang,Ling‑lin Fang 한국탄소학회 2023 Carbon Letters Vol.33 No.6

The flaw of low dispersibility in the metal matrix brought on by graphene's full crystal structure can be improved by the application of ion beam radiation to the surface of the material. Copper atoms are uniformly dispersed on the modified graphene oxide ( GOM) surface after being irradiated to a copper ion beam, and during the sputtering modification, the valence state of copper is changed, resulting in the formation of a new CuO phase on the graphene oxide (GO) surface. Therefore, after copper ion beam irradiation of graphene, the interfacial adhesion between GOM and copper matrix is enhanced, and the wear resistance is significantly improved. When the GOM content is low, it can withstand most of the load during the friction and wear test, which reduces the wear of the copper matrix and the occurrence of fatigue cracks at the interface of the composite material.

High-Definition Computed Tomography for Coronary Artery Stent Imaging: a Phantom Study

Wen Jie Yang,Ke Min Chen,Li Fang Pang,Ying Guo,Jian Ying Li,Huang Zhang,Zi Lai Pan 대한영상의학회 2012 Korean Journal of Radiology Vol.13 No.1

Objective: To assess the performance of a high-definition CT (HDCT) for imaging small caliber coronary stents (≤ 3 mm) by comparing different scan modes of a conventional 64-row standard-definition CT (SDCT). Materials and Methods: A cardiac phantom with twelve stents (2.5 mm and 3.0 mm in diameter) was scanned by HDCT and SDCT. The scan modes were retrospective electrocardiography (ECG)-gated helical and prospective ECG-triggered axial with tube voltages of 120 kVp and 100 kVp, respectively. The inner stent diameters (ISD) and the in-stent attenuation value (AVin-stent) and the in-vessel extra-stent attenuation value (AVin-vessel) were measured by two observers. The artificial lumen narrowing (ALN = [ISD - ISDmeasured]/ISD) and artificial attenuation increase between in-stent and in-vessel (AAI = AVin-stent - AVin-vessel) were calculated. All data was analyzed by intraclass correlation and ANOVA-test. Results: The correlation coefficient of ISD, AVin-vessel and AVin-stent between the two observers was good. The ALNs of HDCT were statistically lower than that of SDCT (30 ± 5.7% versus 35 ± 5.4%, p < 0.05). HDCT had statistically lower AAI values than SDCT (15.7 ± 81.4 HU versus 71.4 ± 90.5 HU, p < 0.05). The prospective axial dataset demonstrated smaller ALN than the retrospective helical dataset on both HDCT and SDCT (p < 0.05). Additionally, there were no differences in ALN between the 120 kVp and 100 kVp tube voltages on HDCT (p = 0.05). Conclusion: High-definition CT helps improve measurement accuracy for imaging coronary stents compared to SDCT. HDCT with 100 kVp and the prospective ECG-triggered axial technique, with a lower radiation dose than 120 kVp application, may be advantageous in evaluating coronary stents with smaller calibers (≤ 3 mm). Objective: To assess the performance of a high-definition CT (HDCT) for imaging small caliber coronary stents (≤ 3 mm) by comparing different scan modes of a conventional 64-row standard-definition CT (SDCT). Materials and Methods: A cardiac phantom with twelve stents (2.5 mm and 3.0 mm in diameter) was scanned by HDCT and SDCT. The scan modes were retrospective electrocardiography (ECG)-gated helical and prospective ECG-triggered axial with tube voltages of 120 kVp and 100 kVp, respectively. The inner stent diameters (ISD) and the in-stent attenuation value (AVin-stent) and the in-vessel extra-stent attenuation value (AVin-vessel) were measured by two observers. The artificial lumen narrowing (ALN = [ISD - ISDmeasured]/ISD) and artificial attenuation increase between in-stent and in-vessel (AAI = AVin-stent - AVin-vessel) were calculated. All data was analyzed by intraclass correlation and ANOVA-test. Results: The correlation coefficient of ISD, AVin-vessel and AVin-stent between the two observers was good. The ALNs of HDCT were statistically lower than that of SDCT (30 ± 5.7% versus 35 ± 5.4%, p < 0.05). HDCT had statistically lower AAI values than SDCT (15.7 ± 81.4 HU versus 71.4 ± 90.5 HU, p < 0.05). The prospective axial dataset demonstrated smaller ALN than the retrospective helical dataset on both HDCT and SDCT (p < 0.05). Additionally, there were no differences in ALN between the 120 kVp and 100 kVp tube voltages on HDCT (p = 0.05). Conclusion: High-definition CT helps improve measurement accuracy for imaging coronary stents compared to SDCT. HDCT with 100 kVp and the prospective ECG-triggered axial technique, with a lower radiation dose than 120 kVp application, may be advantageous in evaluating coronary stents with smaller calibers (≤ 3 mm).

ZNF217 is Overexpressed and Enhances Cell Migration and Invasion in Colorectal Carcinoma

Zhang, Zi-Chao,Zheng, Li-Qiang,Pan, Li-Jie,Guo, Jin-Xing,Yang, Guo-Shan Asian Pacific Journal of Cancer Prevention 2015 Asian Pacific journal of cancer prevention Vol.16 No.6

Background: To investigate the expression and clinical significance of zinc finger protein 217 (ZNF217) in human colorectal carcinoma (CRC). Materials and Methods: The expression of ZNF217 in 60 CRC tissues and matched tumor adjacent tissues, collected between January 2013 and June 2014, was assessed immunohistochemically. The relationship between the expression of ZNF217 and clinicopathlogical features was analyzed by Pearson chi-square test. In addition, siRNA was used to down-regulate the expression of ZNF217 in CRC cells. The effects of ZNF217 for cell migration and invasion were measured by wound healing assay and transwell assay, respectively. Results: The expression level of ZNF217 was significantly higher in CRC tissues than in tumor adjacent tissues (p<0.05), positively correlating with tumor size, lymphatic metastasis and advanced TNM stage (p<0.05). Down-regulation of ZNF217 in CRC cells could significantly suppress cell migration and invasion. Conclusions: ZNF217 is overexpressed in colorectal carcinoma tissues and is associated with tumor malignant clinicopathological features. ZNF217 may promote CRC progression by inducing cell migration and invasion.

Investigation on purification of α-Fe2O3 from zinc smelting iron slag by superconducting HGMS technology

Peng Zhang,Su-qin Li,Zi-jie Guo,Chang-quan Zhang,Chang-qiao Yang,Shuai-shuai Han 한국초전도.저온공학회 2018 한국초전도저온공학회논문지 Vol.20 No.2

Comprehensive utilization of zinc smelting iron slag not only solves environmental problems but also creates huge economic benefits. This study was conducted on the enrichment and recovery of α-Fe2O3 from zinc smelting iron slag by superconducting HGMS technology. Several variables such as slurry flow velocity, slag concentration, magnetic field intensity and the amount of dispersing agent were tested in magnetic separation. In the experiments, obtained optimal magnetic separation parameters were 1.60 T of magnetic flux intensity, 600 mL/min of slurry flow velocity of, 15 g/L of slag concentration of, 0.10 g/L of dispersing agent. Under this condition, the content of α-Fe2O3 was increased from 86.22% to 94.39% that can approach the Chinese national standard requirements (A level) of iron oxide red. It was concluded that using superconducting HGMS technology was an effective method for the purification of α-Fe2O3 from zinc smelting iron slag.

Investigation on purification of α-Fe₂O₃ from zinc smelting iron slag by superconducting HGMS technology

Zhang, Peng,Li, Su-qin,Guo, Zi-jie,Zhang, Chang-quan,Yang, Chang-qiao,Han, Shuai-shuai The Korea Institute of Applied Superconductivity a 2018 한국초전도저온공학회논문지 Vol.20 No.2

Comprehensive utilization of zinc smelting iron slag not only solves environmental problems but also creates huge economic benefits. This study was conducted on the enrichment and recovery of ${\alpha}-Fe_2O_3$ from zinc smelting iron slag by superconducting HGMS technology. Several variables such as slurry flow velocity, slag concentration, magnetic field intensity and the amount of dispersing agent were tested in magnetic separation. In the experiments, obtained optimal magnetic separation parameters were 1.60 T of magnetic flux intensity, 600 mL/min of slurry flow velocity of, 15 g/L of slag concentration of, 0.10 g/L of dispersing agent. Under this condition, the content of ${\alpha}-Fe_2O_3$ was increased from 86.22% to 94.39% that can approach the Chinese national standard requirements (A level) of iron oxide red. It was concluded that using superconducting HGMS technology was an effective method for the purification of ${\alpha}-Fe_2O_3$ from zinc smelting iron slag.