Nano-engineering of Hybrid Titanium Oxide Structure (TiO2) using Pore-widening Concentration for Enhanced Superhydrophilicity

정찬영,최예지 한국부식방식학회 2024 Corrosion Science and Technology Vol.23 No.1

Titanium alloy is gaining attention in the medical industry due to its excellent biocompatibility and osteoconductivity. However, the natural oxide film on the titanium surface is insoluble, resulting in inadequate bone adhesion. Therefore, it is necessary to optimize the contact between biological tissues and implant surfaces, and alter the chemical composition and morphological characteristics of the implant surface. In this study, the anodization method was applied to titanium surface treatment to form a uniform and robust oxide film. Subsequently, a chemical process, pore-widening, was employed to change the morphological characteristics of the oxide film. The concentration of the pore-widening solution was varied at 2, 4, 6, and 8 wt% and the process time was set at 30 and 60 minutes. As the concentration of the pore-widening solution increased the pore diameter of the oxide film increased. Notably, at 6 wt% for 60 minutes, the oxide film exhibited a coexistence of pillars and pores. Based on this, it was determined that surface roughness increased with higher concentration and longer process time. Additionally, the presence of pillars and pores structures maximized hydrophilicity. This study provides insights into enhancing the surface properties of titanium for improved performance in medical implants.

알루미늄 6061 합금 양극산화 후 열처리에 따른 표면 특성 관찰

정찬영,이승민 한국부식방식학회 2022 Corrosion Science and Technology Vol.21 No.6

Anodization is a representative electrochemical surface treatment method that can improve both heat resistance and corrosion resistance by forming an anodization film on the surface of the aluminum. However, these properties can be changed after an additional heat treatment process. In this study, Al 6061 was subjected to an anodization process at 60 V for 1 hour, 5 hours, or 9 hours. An additional heat treatment process was performed at 500 oC for 30 minutes. Field emission scanning electron microscopy (FE-SEM) analysis revealed that the thickness of the anodized film was increased in proportion to the anodization time. Both pore size and pore diameter of the anodized film was also increased after anodization. After an additional heat treatment process, there were no significant changes in the thickness, pore size, or pore diameter of the anodized film. Heat resistance was confirmed through thermal analysis and chemical resistance was evaluated with a potentiodynamic polarization test.

양극산화 방법을 이용한 기능성 알루미늄 3003 합금의 표면 특성 및 부식 거동 연구

정찬영,김지수 한국부식방식학회 2022 Corrosion Science and Technology Vol.21 No.4

Anodizing is an electrochemical surface treatment method conferring corrosion resistance and durability by forming a thick anodization film on the metal surface. Aluminum has a long service life and high thermal conductivity and formability, as well as excellent corrosion resistance. Aluminum 3003 alloy has improved formability, strength, and corrosion resistance due to the addition of a small amount of manganese. However, corrosion occurs in seawater and environments polluted with corrosion-inducing substances, which reduce corrosion resistance. Therefore, it is necessary to artificially form a thick anodized film to improve corrosion resistance. In this study, the anodization treatment time was 4 minutes, and voltages of 10 V, 20 V, 30 V, 40 V, 50 V, 60 V, 70 V, 80 V, 90 V, and 100 V were applied. The thickness and pore size of the oxide film increased according to the applied voltage. A barrier film was formed under voltage conditions from 10 V to 50 V, and a porous film was formed under voltage conditions from 60 V to 100 V. After anodizing, coating was applied. Wettability and corrosion resistance were observed before and after coating according to the surface shape and thickness of the oxide film.

알루미늄 1050 합금의 양극산화 시간에 따른 산화피막 성장 거동 및 부식 손상 연구

정찬영,최예지 한국부식방식학회 2022 Corrosion Science and Technology Vol.21 No.4

Aluminum 1000 series alloy, a pure aluminum with excellent workability and weldability, is mainly used in the ship field. Aluminum alloy can combine with oxygen in the atmosphere and form a natural oxide film with high corrosion resistance. However, its corrosion resistance and durability are decreased when it is exposed to a harsh environment for a long period of time. For solving this problem, a porous oxide film can be formed on the surface using an anodizing treatment method, a typical surface technique among various methods. In this study, aluminum 1050 alloy was anodized for 2 minutes, 6 minutes, and 10 minutes. The structure and shape of the oxide film were then analyzed to determine the corrosion resistance according to the thickness of the oxide film that changed depending on working condition using 15 wt% NaCl. After it was immersed in NaCl solution for 1, 5, and 10 days, corrosion damage was observed. Results confirmed that the thickness of the oxide film increased as the anodization time became longer. The depth of surface damage due to corrosion became deeper when the film was immersed in the 15 wt% NaCl solution for a longer period of time.

계절에 따른 습지 내 저서성대형무척추동물 모니터링을 통한 지하수의존생태계 특성 평가

정찬영,최지웅,문희선,김동훈,문상호,오용화,한지연,오설란,김용철,Jeong, Chanyoung,Choi, Ji-Woong,Moon, Hee Sun,Kim, Dong-Hun,Moon, Sang-Ho,O, Yong-Hwa,Han, Ji Yeon,Oh, Seolran,Kim, Yongcheol 한국지하수토양환경학회 2021 지하수토양환경 Vol.26 No.6

Wetlands are one of the most representative groundwater dependent ecosystems(GDEs) that require access to groundwater on a permanent or intermittent basis to maintain their biological communities and ecological processes. In this study, the seasonal characteristics of the GDEs in Baekseok Reservoir Wetland were evaluated through the monitoring of the temporal and spatial community of benthic macroinvertebrates in the wetland. The appearance of benthic macroinvertebrates appearance was changed seasonally depending on environmental factors such temperature, precipitation and water level for their habitat and it also showed the clear spatial difference in the wetland. The scores of Diversity index(H'), Richness Index (R1) and the Ecological score of benthic macroinvertebrates (TESB/AESB) were relatively high at St.3 and 4(i.e., north area) where groundwater inflows into wetland(i.e., high ²²²Rn conc.). The statistical analysis (ANOVA test and PCA) investigated the correlation among the benthic macroinvertebrates' community, groundwater level, wetland water level and water quality. The results showed that the community of benthic macroinvertebrates at St. 3 and 4 in Baekseok Reservoir Wetlands was spatially dependent on groundwater level and groundwater inflow. The characterization and assessment of GDEs requires understanding the hydrological, biogeochemical and biological process and this study will provide information for characterization and assessment of GDEs.

Fabrication of Superhydrophobic Aluminum Alloy Surface with Hierarchical Pore Nanostructure for Anti-Corrosion

정찬영,지혜정 한국부식방식학회 2019 Corrosion Science and Technology Vol.18 No.6

Aluminum and its alloys have been widely used in various fields because of low weight, high strength, good conductivity, and low price. It is well known that aluminum alloys that cause natural oxide film can inhibit corrosion in wet, salty environments. However, these oxides are so thin that corrosion occurs in a variety of environments. To prevent this problem, an electrochemical anodizing technique was applied to the aluminum alloy surface to form a thick layer of oxide and a unique oxide shape, such as a hierarchical pore structure simultaneously combining large and small pores. The shape of the structures was implemented using stepwise anodization voltages such as 40 V for mild anodizing and 80 V for hard anodizing, respectively. To maximize water repellency, it is crucial to the role of surface structures shape. And a hydrophobic thin film was coated by 1H, 1H, 2H, 2H-Perfluorodecyltrichlorosilane (FDTS) to minimize surface energy of the structure surface. Thus, such nanoengineered superhydrophobic surface exhibited a high water contact angle and excellent corrosion resistance such as low corrosion current density and inhibition efficiency.

3D 프린팅 기술을 이용한 누에 알 미세주입 기술 개선

정찬영,이창훈,석영식,용상엽,김성완,김기영,박종우 한국응용곤충학회 2022 한국응용곤충학회지 Vol.61 No.1

Silkworms, which have for long been used as an insect resource for industrialization, have recently attracted attention as potential bio-factories for the production of novel biomaterials. In this regard, material production is typically achieved based on transformation technology, mediated via microinjection, in which a target gene is inserted into eggs containing an embryo. However, an essential step in the microinjection procedure is egg fixation, which can be a time-consuming and laborious task. Therefore, in this study, using the 3DCADian program, we adopted a 3D printing approach to model egg liners and glue drawers, which can contribute to facilitating egg alignment and fixation, thereby enhancing transformation efficiency by reducing time consumption and fatigue. After rendering using Fusion 360, the two supplementary tools were produced by printing with nylon resin (PA12) and Sinterit Lisa Pro. Subsequent analysis of the time required to fix eggs on glass slides using the two manufactured tools, revealed that the processing time was reduced by approximately 18.6% when the two tools were used compared with when these tools were not used. These innovations not only reduced fatigue but also contributed to more effective use of the microscope and manipulator for microinjection. Consequently, we believe that with additional research and refinement, the egg liner and glue drawer developed in this study could be used to enhance silkworm transformation efficiency and study similar transformation systems in other industrial insects. 오래전부터 산업곤충으로서 이용되어온 누에는 최근 바이오 신소재 생산을 위한 생체공장으로써 주목받고 있다. 소재생산을 위해서는 주로 형질전환 기술을 이용하게 되며, 이는 배아가 있는 알 속으로 목적 유전자를 삽입하는 마이크로인젝션(microinjection) 방식으로 이루어진다. 마이크로인젝션을 위해서는 알을 고정하는 과정이 필수적이며 시간 소모 및 피로도가 높은 작업이다. 따라서 본 연구에서는 시간 소모 및 피로도 개선을 통하여 형질전환 효율을 높이고자 3D 프린팅을 이용하여 알의 정렬 및 고정에 도움을 줄 수 있는 알 배열판(egg liner) 및 접착제 줄눈판 (glue drawer)을 3DCADian 프로그램을 이용하여 모델링하고, Fusion 360를 이용하여 3차원 도면을 제작 후 프린팅하여 제작하였다. 제작된두 도구를 이용하여 슬라이드 글라스에 알을 고정하고, 소요된 시간을 분석한 결과 도구를 사용하지 않았을 때에 비하여 2가지 도구를 이용했을때 작업시간이 약18.6% 감소하였으며, 연구자의 작업 편의성을 향상시키고 마이크로인젝션을 위한 현미경 및 로봇 팔(manipulator) 조작을 유리하게 하였다. 따라서 알의 배열 수 또는 조작 편의성을 개선할 수 있는 추가적인 연구 및 개량이 이루어진다면, 알 배열판 및 접착제 줄눈판이 누에 형질전환 효율성 개선 및 다른 산업 곤충의 형질전환 연구에도 이용될 수 있을 것으로 판단된다.

VMD 매체로서의 POP 광고 디자인에 대한 연구(광주지역3개 백화점을 중심으로)

정찬영,조윤아 한국비쥬얼디자인학회 2001 한국디자인포럼 Vol.6 No.-

These days, the marketing of products are rapidly changing due to the opening of the distribution market. It is also becoming more systematic. The development of dvanced technology brought a progress in distribution. In these terms, the market has become more mature and marketig communication has become more diverse in order to appeal to customers. POP Advertizement as VMD(Visual Merchandising) media was developed as a means to increase sales. It connects products to customers and is in charge of ensuring and exploiting markets. Advertisements which are easily accessible inform the public about new products, hteir appealing characteristics and identify the location where they can be purchased. POP Advertizement is suitable in a variety of situations in which cubic materials are used. it requires attention from the area of design. In an environment of changing distribution, images are considered as important when customers can perceive visual information and can make decisions about it. In this context, this study aims to do a theoretical examination of POP Advertisements and aims to look at the current tendency to handle advertising through analysing three major department stores. An effective design plan is offered to increase effectiveness and the characteristics of a department store are considered. It expected that POP Advertizement as VMD media achieves a new recognition and an increase of quality when design education is offered in business and department stores.

Kawasaki disease shock syndrome rescued by a combination of extracorporeal membrane oxygenation, steroids, and intravenous immunoglobulin

정찬영,고 훈,변정희,김태홍,이형두 대한소아응급의학회 2022 대한소아응급의학회지 Vol.9 No.1

Kawasaki disease shock syndrome (KDSS) is defined as a sustained decrease in systolic blood pressure or signs of poor perfusion. Some children with KDSS are refractory to conventional therapy, such as intravenous immunoglobulin (IVIG). A 4- year-old boy with Kawasaki disease was referred to the emergency department. Despite the conventional therapy, his vital signs and cardiac function worsened. The boy promptly underwent extracorporeal membrane oxygenation (ECMO), which did not relieve the symptoms. Subsequently, he underwent methylprednisolone pulse therapy and the second cycle of IVIG therapy. Two days after the start of a combination of ECMO, steroids, and IVIG started, his clinical condition was stabilized, and finally, ECMO was removed. This case highlights the combination of ECMO, steroids, and IVIG as a treatment option for children with IVIG-resistant KDSS.

슬관절의 통증과 기능장애의 평가도구에 관한 연구

정찬영,김은정,황민섭,조현석,김경호,이승덕,김갑성 대한침구의학회 2010 대한침구의학회지 Vol.27 No.2

Objectives : The knee pain is the main reason of getting acupuncture treatment. In order to have confidence in the results of a study, it is necessary to establish that questionnaire is both valid and reliable in questionnaire related study. The aim of this study was to review the instruments that are currently in sue for assessing the knee joint. Methods : A literature study was performed to choose appropriate scales for assessment for pain and the function of the knee. Theoretically based scales were selected for review. Therefore, 18 scales for knee and 9 scale for pain were reviewed. the status of scales involved in knee treatment of acupuncture throughout several countries was evaluated. Results & Conclusion : Lysholm Knee Scoring Scale, Cincinnati knee rating system(CKRS) are adequate for ligament injury in knee. International Knee Documentation Committee scoring system(IKDC) may become a publication requirement for journals in view of the international standing of the committee. The available outcome measure for use in osteoarthritis are Western Ontario and McMaster Universities Osteoarthritis Index(WOMAC), Lequesne Functional Severity Index(LFI) and Knee Injury and Osteoarthritis Outcome Score(KOOS), and in rheumatoid arthritis are McMaster-Toronto Arthritis patient function preference questionnaire(MACTAR), Quality of Life-Rheumatoid Arthritis Scale(QoL-RA Scale). Visual analog scale(VAS), verbal rating scale(VRS) are commonly used for the standard pain scale. For long term follow-up study The Medical Outcomes Study Short Form-36(SF-36), Arthritis Impact Measurement Scales(AIMS), Health Assessment Questionnaire(HAQ) should be included. Each measurement has its own composition and characteristics. Their validity, reliability, responsiveness and practical characteristics were already evaluated. We found 20 domestic and 28 overseas papers about knee treatment using acupuncture assessed with knee scales.