• Journal of the Korean Society of Radiology
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• v.83 no.1
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• pp.189-193
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• 2022

Hemorrhage after pancreaticobiliary surgery is an infrequent but fatal complication. It is primarily caused by rupture of the pseudoaneurysm, and treatment options include endovascular coil embolization or endovascular stent-graft placement. Herein, we report a case of migration of an arterial stent-graft that was placed in the common hepatic artery to treat pseudoaneurysm after pylorus-preserving pancreaticoduodenectomy. The stent-graft migrated to the jejunum and was eventually excreted from the body.

• Journal of Chest Surgery
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• v.34 no.9
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• pp.698-703
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• 2001

Background: Endovascular stent-graft insertion in aortic diseases is now generally accepted as an attractive alternative treatment modality. We reviewed our clinical experiences of endovascular stent-graft insertion in thoracic aorta. Material and Method: Since 1995, we performed 8 cases of endovasclar stent-graft insertion. Preoperative diagnoses were aortic aneurysms in 4, traumatic aortic ruptures in 3, and ruptured aortic pseudoaneurysm in 1. All procedures were performed in angiography room with the guidance of fluoroscopy. The stent-graft device is a custom-made 0.35mm thickness Z-shaped stainless steel wires, intertwined with each other using polypropylene suture ligation. It is covered with expanded Dacron vascular graft. Result: All procedures were performed successfully. Follow-up studies revealed 2 minimal perigraft leakages. There was no significant leakage or graft migration. 2 patients expired due to multiple organ failure and fungal sepsis. Other survivors(6) are doing well. Conclusion: Endovascular stent-graft insertion is relatively saft and effective treatment modality in the managment of various types of aortic diseases. In may be an effective alternative in aortic diseases of great surgical risk.

• Analytical Science and Technology
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• v.12 no.1
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• pp.7-12
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• 1999

The cation-exchange adsorbent (CEA) was prepared by radiation-induced grafting of glycidyl methacrylate (GMA) onto polypropylene (PP) fabric and its subsequently phosphonation. The adsorption characteristics of $Pb^{2+}$, $Cu^{2+}$ and $Co^{2+}$ for the CEA were discussed. In the grafting of GMA onto PP fabric, the degree of grafting (%) increased with increasing reaction time, reaction temperature, and pre-irradiation dose. The maximum grafting yield was observed around 60% GMA concentration. The content of phosphoric acid ranges from 2.5 to 3.5 mmol/g with the 85% phosphoric acid. The adsorption of $Pb^{2+}$, $Cu^{2+}$ and $Co^{2+}$ by the CEA was enhanced with increasing phosphoric acid content. The order of adsorption capacity of CEA was $Pb^{2+}$>$Co^{2+}$>$Cu^{2+}$.

• Composites Research
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• v.32 no.6
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• pp.335-341
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• 2019

In this study, an acrylic acid (AAc) was grafted on a polypropylene (PP) nonwoven fabric using electron beam irradiation. Electron beam grafting was carried out under various conditions to produce AAc grafted PP (PP-g-AAc) nonwoven fabric having a grafting yield of about 50% at radiation dose of 100 kGy and a monomer concentration of 60%. The physical and chemical properties of PP-g-AAc nonwoven fabric were evaluated by SEM, ATR-FTIR, thermal analysis and tensile strength. The morphology of PP and PP-g-AAc nonwoven fabric confirmed by SEM showed no significant change, and it was judged that AAc was introduced into PP nonwoven fabric from ATR-FTIR. PP-g-AAc nonwoven fabric showed an increase in tensile strength and a decrease in tensile strain compared to PP nonwoven fabric. However, since change of value is not significant, it is considered that there is no significant influence on the physical characterization. Adsorption experiments of PP-g-AAc nonwoven fabric on various ions showed selective adsorption behavior for lead ion. In conclusion, the electron beam radiation-induced PP-g-AAc nonwoven fabric is expected to be applied as an effective adsorbent for the adsorption of lead ions.

• Applied Chemistry for Engineering
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• v.3 no.1
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• pp.130-137
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• 1992

The Graft copolymerization of acrylonitrile(AN) and styrene(ST) onto chloroprene rubber(CR) were carried out with benzoyl peroxide(BPO) as an initiator. The synthesized graft copolymer(ACS) was separated from polymeric mixture by the extraction with ethyl acetate and n-hexane, acetone and methanol, dimethylformamide(DMF) and methanol mixed solvent systems. The graft copolymer obtained, acrylonitrile-chloroprene-styrene(ACS) was identified by IR spectrophotometer. The effect of mole ratio of styrene to acrylonitrile, reaction time and temperature, initiator concentration, CR content and solvents on graft copolymerization were examined. It was observed that the grafting efficiency increased with [ST]/[AN] mole ratio and reaction time. The grafting efficiency increased with increasing initiator concentration and CR content. The maximum grafting efficiency was obtained when the mole ratio of [ST]/[AN] was 1.5 and reaction was made at 40hrs, and $70^{\circ}C$ using chloroform/toluene mixed solvent. The thermal properties, light resistance and flammability of ACS were compared with those of ABS and AES. It was found that flame retardancy of related polymers increased in the order ACS>ABS>AES. The thermal stability of ACS was greatly improved when compared with ABS or AES. Morphology of ACS was also investigated by using a transmisson electron microscope(TEM).

• Proceedings of the Korean Fiber Society Conference
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• 1998.10a
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• pp.453-456
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• 1998

고분자들을 배합하여 기계적, 물리적, 화학적 성질이 우수한 새로운 고분자 재료를 제조할 때 이들 고분자의 상용성을 증가시켜 줄 수 있는 상용화제의 존재가 필수적인데, 주로 블록이나 그라프트 공중합체들이 많이 이용되고 있다. 이러한 공중합체들은 아주 최소량이 사용되고서도 소기의 목적을 달성할 수 있어야 하는데, 이를 위해서는 이러한 공중합체들은 분자구조상 몇 가지 조건을 만족해야 한다. 예를 들면 계면에 존재하면서 넓은 표면적을 감싸주어야 하고 블렌드되는 고분자들과 아주 잘 섞여야 한다는 것 등이 그것이다. (중략)

• Journal of Chest Surgery
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• v.43 no.6
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• pp.729-733
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• 2010

Endovascular treatment of the aortic aneurysm with a stent graft is rapidly evolving. We describe here a case of hybrid TEVAR (thoracic endovascular aortic repair) in which the stent grafts were placed in the aortic arch after debranching of the arch vessels. The patient had undergone ascending aorta replacement for acute type I aortic dissection 2.5 years earlier. The aneurysmal change of the distal dissection progressed with time. A provisional bypass surgery from the ascending aorta to the innominate artery and left carotid artery was performed and then stent grafts were inserted via an antegrade route that covered the whole aortic arch and proximal descending thoracic aorta.

• Polymer(Korea)
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• v.26 no.2
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• pp.160-167
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• 2002

We synthesized HPP-g-GMA copolymer using pre-irradiation method by E-beam and aminated HPP-g-GMA using amination reaction. Degree of grafting increased with increasing GMA monomer concentration and showed the maximum value of 130% at 1.46 M of GMA. The degree of amination increased with increasing the degree of grafting. When the degree of grafting was 100%, degree of amination showed the maximum value of 37.4%. The ion exchange capacity of aminated HPP-g-GMA was about 3.78 meq/g, and it showed remarkable adsorption ability of hollow fiber ion exchanger. Through the BET analysis, the surface area of aminated HPP-g-GMA was 54.83 $\m^2/g$ and the mean pore size was $26\AA$. These showed the decrease of surface area and the slight increase of the mean pore size. SEM results show that the thickness of fiber increased after the step of reaction and there pore blocking phenomena was not observed. The aminated HPP-g-GMA was synthesized successfully and found to be suitable for the adsorption and separation of anion.

• Journal of Chest Surgery
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• v.43 no.1
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• pp.92-95
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• 2010

Endovascular stent grafting is regarded as a promising alternative approach to open surgical repair for treating various aortic diseases in high risk patients. We report here on a case of a 79-year-old female who underwent endovascular stent-graft insertion in the ascending aorta for treating a complicated ascending aortic rupture that occurred secondary to radiation necrosis during the treatment of recurrent breast cancer.

• Polymer(Korea)
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• v.26 no.1
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• pp.121-127
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• 2002

We investigated uranium adsorption and adsorption process characteristics in brine water, changing column bed height packed with amidoximated polypropylene-g- acrylonitrile (AOPP-g-AN) fibrous ion-exchanger. Swelling ratios of AOPP-g-AN in fibrous ion-exchanger were 8.54g/g $H_2O_2$ and 8.87 g/g for $H_2O_2$ solvent respectively. Ion exchange capacity increased with degree of graft and showed the maximum, 3.99 meq/g at 100% degree of graft. In batch process, uranium adsorption had reached an initial equilibrium in 10 min with the adsorption rate of 9.5 mg/min. Finial adsorption capacity was 3.95 meq/g, and pH effect could not be observed. In continuous process, adsorption capacity depended on various packing ratios and showed the maximum, 3.92 meq/g at L/D=1. In L/D<2, breakthrough curve was shown two step by channeling flow and ununiform adsorption. Breakthrough time and adsorption capacity were 26 min and 3.63 meq/g, respectively, in brine water adsorption. When compared with actual brine water and model solution, there was no significant difference of adsorption characteristics.