희토류 원소의 분리 및 정량을 위한 이온회합 크로마토그래피

이승화,이철,정구순,Lee, Seung Hwa,Lee, Cheol,Jeong, Koo Soon 대한화학회 1990 대한화학회지 Vol.34 No.1

모자나이트 광물 중에 포함된 각각 희토류 원소를 이온회합 크로마토그래피 방법으로 분리 및 정량하였다. 정량하기 전에 양이온교환수지(Dowex 5OW-X8) 칼럼으로 희토류 원소를 집단 분리하였다. 이 때 수지 칼럼에 의하여 희토류 원소가 정량적으로 회수되며, 시료 중의 공존이온으로부터 깨끗이 분리됨을 방사성 추적자 및 유도쌍 결합 분광-질량분석법(ICP-MS)으로 각각 확인 하였다. 역상 칼럼($\mu$-Bondapak $C_{18}$)에 의하여 미량(ppm)의 희토류 원소를 pH 4.6의 $\alpha$-hydroxyisobutyric acid으로 0.05M부터 0.3M까지 기울기 용출하여 각각 분리하였다. 희토류 원소와 PAR (4-(2-pyridylazo)-resorcinol monosodium salt)과의 포스터 칼럼 착색반응을 통하여 각각의 희토류 원소를 검출하였다. An ion-association chromatography was applied for the separation and determination of individual rare earth elements (REE) contained in mineral monazite. Prior to the determination, the group separation of REE was achieved by a cation exchange column of Dowex 5OW-X8 resin. The quantitative recovery of REE by the resin column, free from coexisting elements in monazite, was confirmed with radioactive tracers as well as with ICP-MS. Individual REE at ppm level was separated on reversed-phase column ($\mu$-Bondapak $C_{18}$) using gradient elution from 0.05 to 0.3 M $\alpha$-hydroxyisobutyric acid at pH 4.6. The individual REE was detected at 546 nm following post-column reaction with PAR (4-(2-pyridylazo)-resorcinol monosodium salt).

중년기 삶의 의미 유형에 따른 분류 및 특성

이승화,민경화 한국상담학회 2015 상담학연구 Vol.16 No.5

The present study was conducted to categorize middle-aged adults based on presence of meaning and search for meaning and to identify differences in mid-life crisis and psychological well-being among the groups. For this purpose, mid-aged(40~65) adults participated in the survey. A latent profile analysis(LPA) was used to classify latent groups and one-way ANOVA. were used to analyze data. As a result, four distinguishable profiles were verified: Class1(The Low Search-Low Presence profile), Class2(The Mid Search-Mid Presence profile), Class3(The Low Search-High Presence profile), Class4(The High Search-High Presence profile). These four classes showed differences in mid-life crisis and psychological well-being. Class4(The High Search-High Presence profile) and Class3(The Low Search-High Presence profile) showed high score on psychological well-being and Class1(The Low Search-Low Presence profile) was the highest score on mid-life crisis. Class3(The Low Search-High Presence profile) was the lowest score on mid-life crisis and emotional crisis and individuation process in sub-factors of mid-life crisis and it also showed lowest score on environmental control and autonomy in sub-factors of psychological well-being. According to these characteristics, Class1(The Low Search-Low Presence profile) was named ‘The Search for meaning indifference type’, Class2(The Mid Search-Mid Presence profile) was named ‘The Search for meaning progress type’, Class3(The Low Search-High Presence profile) was named ‘The Unawareness satisfaction type’ and Class4(The High Search-High Presence profile) was named ‘The Meaning in life satisfaction type’. This study is meaningful in that it explores naturally occurring profiles of the meaning in life and searches psychological function so that this study provides basic information for mid-life clients to plan specific intervention strategies for each group in counseling. 본 연구는 삶의 의미 추구 및 발견 수준에 따라 중년기 대상자들이 서로 다른 집단으로 구분되는지 살펴보고, 이들의 심리적 특성과 적응수준을 알아보기 위해 각 집단이 중년기 위기감과 심리적 안녕감에서 어떠한 차이를 보이는지 확인하고자 하였다. 이러한 연구목적에 따라 40세에서 65세의 중년기 남녀 554명을 대상으로 설문을 실시하여 잠재프로파일 분석(LPA: Latent Profile Analysis)으로 집단을 구분하고, 집단 간 일원변량분석을 실시하였다. 그 결과, 삶의 의미추구와 의미발견 수준의 조합에 따라 집단1(의미추구 저-발견 저), 집단2(의미추구 평-발견 평), 집단3(의미추구 저-발견 고), 집단4(의미추구 고-발견 고) 네 개의 서로 다른 집단이 확인되었으며 차이 검증결과, 네 집단은 중년기 위기감과 심리적 안녕감에서 차이를 보였다. ‘집단4(의미추구 고-발견 고)’와 ‘집단3(의미추구 저-발견 고)’은 심리적 안녕감이 가장 높았으며, ‘집단1(의미추구 저-발견 저)’은 중년기 위기감이 가장 높았다. ‘집단3(의미추구 저-발견 고)’은 중년기 위기감에서 가장 낮았고, 하위요인 중 정서적 위기감과 개별화 과정이 가장 낮았고, 심리적 안녕감 하위요인 중 환경 통제력과 자율성이 낮았다. 이러한 의미추구와 의미발견 수준, 중년기 위기감, 심리적 안녕감에서의 차이를 종합하여 집단 특성을 반영한 결과, 집단1(의미추구 저-발견 저)은 ‘의미추구 무관심형’, 집단2(의미추구 평-발견 평)는 ‘의미추구 진행형’, 집단3(의미추구 저-발견 고)은 ‘개별화가 낮은 만족형’, 집단4(의미추구 고-발견 고)는 ‘의미 충족형’으로 명명하였다. 본 연구의 의의는 중년기의 삶의 의미를 의미추구와 의미발견 수준에 따라 집단을 구분하여 각 집단에 따른 심리적 기능을 알아봄으로써 상담 장면에서 서로 다른 특성을 가진 중년기 내담자들을 위한 구체적인 개입 전략을 세우는데 필요한 정보를 제공한 점에 있다.

황달과 복통을 주소로 내원한 Hemosuccus pancreaticus

이승화,최윤선,소찬수,고동희,최민호,장현주,계세협,이진 대한내과학회 2009 대한내과학회 추계학술대회 Vol.2009 No.-

제17차 IWRA 세계물총회 개최지 대구

이승화,Lee, Seung-Hwa 한국수자원학회 2019 물과 미래(한국수자원학회지) Vol.52 No.8

A Case of Endoscopic Resection of a Colonic Semipedunculated Leiomyoma

이승화,허건웅,정유석 대한대장항문학회 2011 Annals of Coloproctolgy Vol.27 No.4

During colonoscopic examination, epithelial lesions, such as adenomatous polyps, are frequently encountered, unlike sub- epithelial lesions, such as leiomyomas, which are uncommon. A colonic leiomyoma is a rare tumor, originating either from the mucularis mucosa or from the proper muscle, and accounts for only 3% of all gastrointestinal leiomyomas. Colonic leio- myomas are usually benign and asymptomatic. However, they can sometimes cause symptoms, ie, abdominal pain, intesti- nal obstruction, hemorrhage, and perforation. The traditional management option for a colonic leiomyoma is surgical re- section. Recently, with the development of endoscopy devices and techniques, the endoscopic resection has been consid- ered as an alternative treatment option. We experienced a patient with a leiomyoma that was diagnosed during colonoscopy. The leiomyoma was resected endoscopically without complication. We report this case with a review of the literature.

전처리 방법에 따른 새송이버섯 스낵의 품질특성

이승화,남형욱,김우현,조항혁,민동규,권상철 한국산학기술학회 2024 한국산학기술학회논문지 Vol.25 No.3

This study examined the textural properties, acidity, lipid oxidation, total polyphenol content, total flavonoid content, DPPH radical scavenging activity, and ABTS radical scavenging activity of shiitake mushroom snacks based on different pre-processing methods. The goal was to optimize the production of functional snacks with shiitake mushrooms. Three pre-processing methods, raw material (PE), frozen (FP), and soaking in syrup (SP), were selected, and shiitake mushroom snacks were manufactured by slicing them uniformly to a thickness of 1 mm. The hardness was highest in SP, showing a value of 537.90±9.19, while the acidity was lowest in SP, with a value of 0.75±0.07 mg/kg. Lipid oxidation was similar in the PE, FP, and SP groups. The total polyphenol content was highest in SP, recording a value of 42.98±0.30 mg GAE/g. Similarly, the total flavonoid content was highest in SP, reaching 64.45±0.08 mg CE/g. Among the pre-processing methods, FP resulted in the highest DPPH radical scavenging activity of 4.34±0.01 mg AEAC/g. SP produced the highest antioxidative activity at 91.67±0.00%, according to the ABTS radical scavenging test. Based on these results, soaking in syrup is the most effective pre-processing method that enhances the antioxidant activity of shiitake mushrooms and contributes to improved textural properties.

곤충병원선충(Steinernema carpocapsae Weiser)의 냉동저장법

이승화,김용균,한상찬 한국응용곤충학회 2000 한국응용곤충학회지 Vol.39 No.3

Cryopreservation of infective juveniles of entomopathogenic nematode, Steinernema carpocapsae Weiser, was conducted at $-190^{\circ}C$ liquid nitrogen and its, efficacy was analysed on nematode survival and pathogenicity with glycerol pretreatments and storage periods. Infective juveniles were pre-treated before being frozen by incubating the nematodes in 22% glycerol for each of 6, 12, and 24 h, followed by 70% methanol at $0^{\circ}C$ for 10 minutes. Just after glycerol and methanol incubations, subsamp1es of the nematodes were resuspended in 0.85% saline and maintained during 24h for viability determination. Different glycerol incubation periods significantly affected the nematode susceptibility to methanol infiltration. Six hour incubation in glycerol resulted in much less nematode survival than did 12 h or 24 h incubation. About 70% of the infective juveniles frozen at $-190^{\circ}C$ for 5 months, preincubat-ed in glycerol at least for 12h, were able to survive after being resuspended in 30°C saline. They did not also show any change in their pathogenicity during cryopreservation. These results suggest an improved technique for long-term storage of the entomopathogenic nematodes. 곤충변원성충(Steinernema carpocapsae Weiser)의 감염태 유충에 대한 액체질소( $-190^{\circ}C$)냉동 저장하는 방법을 개발하기 위하여, 냉동보관 전처리 과정 및 저장기간에 따른 선충생존율과 감염력 변이를 조사하였다. 냉동저장 전에 22% 글리세롤로 선충은 6, 12, 24시간 동안 배양한 후 70% methanol($0^{\circ}C$)안에 10분간 유지하였다. 글리세롤과 methanol에 넣어 둔 샘플을 0,85% 식염수에 넣어 24시간 유지한 후 생존능력을 측정하였다. 글리세롤 배양시간에 따른 선충 생존율의 차이는 없었으나, methanol처리에서는 글리세롤 처리 시간이 길수록 선충 생존율이 높게 나타났다. 냉동저장에 따른 선충의 생존율은 글리세롤 배양시간이 짧았던 처리(6시간)를 제외하고는 5개월 동안 평균 70% 이상으로 높게 나타났다. 냉동저장 되었던 선충의 곤충감염율은 저장기간에 관계없이 90% 이상을 나타내었다. 이상의 결과는 곤충병원선충이 냉동저장에 의해 장기간보존이 가능하다는 것을 제시한다.

부모의 양육태도와 자녀의 성격특성 및 학교적응과의 관계

이승화 圓光大學校 敎育問題硏究所 2001 敎育硏究 Vol.- No.20

Fabrication of nano-sized reduced graphene oxide-gold nanocomposites for enhanced photothermal, photodynamic effect

이승화,김소연 한국공업화학회 2020 한국공업화학회 연구논문 초록집 Vol.2020 No.-

Recently, nano-sized graphene oxide (NGO) nanocomposites have attracted increasing attention for biomedical applications, such as drug delivery system, photothermal and photodynamic therapy of cancer. In particular, reduced graphene oxide (rGO) composites have an excellent photothermal conversion efficiency compared to normal GO composites. However, it is difficult to use in vivo experiments since GO tends to reduce the number of functional groups after reduction, resulting poor dispersibility in water. In this work, we prepared the gold nanorods (GNRs) combined with the surface- modified rGO, which can further improve the dispersibility and biocompatibility of rGO composites. In addition, Ce6 was attached on rGO and the photodynamic effect was also confirmed. The physicochemical properties, morphologies and optical properties of rGO-GNRs composites were determined. Their photothermal stabilities were also investigated upon exposure to near-infrared (NIR) light irradiation.

물산업 육성을 위한 국가 물산업클러스터 조성사업

이승화 대한지방행정공제회 2018 地方行政 Vol.67 No.778