Misorientation Characteristics at the Growth Front of Abnormally-Growing Goss Grains in Fe–3%Si Steel

Tae‑Young Kim,Tae‑Wook Na,Hyung‑Seok Shim,Yong‑Keun Ahn,Yong‑Kwon Jeong,Heung Nam Han,Nong‑Moon Hwang 대한금속·재료학회 2021 METALS AND MATERIALS International Vol.27 No.12

Penetrating morphologies at the growth front of abnormally-growing Goss grains in Fe–3%Si steel was examined in view ofthe possibility that they are the two-dimensional section of the solid-state wetting (SSW) along the triple junction line. Toobtain the statistically meaningful data, 102 penetrated grain and 204 penetrating abnormally-growing Goss grain morphologieswere examined. The misorientation angles of penetrating and penetrated grains were measured by electron backscattereddiffraction. Among the 102 examined penetrated grain boundaries, none has low misorientation angles less than 15°,whereas 17.2% of the 204 penetrating grain boundaries have low misorientation angles, and 23.5% of them have coincidencesite lattice boundaries. Besides, boundary energies of penetrating Goss grains, which were estimated from misorientationangles of the three grains in the penetrating morphology, satisfied the energetic condition for SSW along the triple junctionline. These results imply that the abnormal grain growth of Goss grains in Fe–3%Si steel occurs by the mechanism of subboundaryenhanced SSW.

Effect of Asymmetric Hot Rolling on the Texture Evolution of Fe–3%Si Steel

Tae‑Wook Na,Hyung‑Ki Park,박창수,Hyung‑Don Joo,Jong‑Tae Park,Heung Nam Han,Nong‑Moon Hwang 대한금속·재료학회 2018 METALS AND MATERIALS International Vol.24 No.6

In Fe–3%Si steel, the hot rolling process affects not only the hot rolling texture but also the primary recrystallization texture. Here, the effect of asymmetric hot rolling was studied by comparing the difference in the texture evolved between asymmetricand symmetric hot rolling. The effect of asymmetric hot rolling on the texture of primary recrystallized Fe–3%Si steel wasalso studied. The symmetric hot rolling of Fe–3%Si steel produces a rotated cube texture at the center but Goss and coppertextures near the surface. Asymmetric hot rolling tends to produce Goss and copper textures even at the center like thetexture near the surface. After primary recrystallization, the dominant texture at the center changes from {001} <210> to{111} <112> and the new texture has a higher fraction of the grains which make the low energy boundary with Goss grainsthan that of symmetric hot rolling.

연령에 따른 한국인의 음향지표 변화와 특성

김형태,조승호,윤성문,선동일,김민식 대한이비인후과학회 2000 대한이비인후과학회지 두경부외과학 Vol.43 No.1

1993년에 유행한 무균성 뇌막염 : 서울지역 소아를 대상으로 The study of pediatric patients in Seoul, with the emphasis on the isolation of causative agent

문형남,고태성,박영서,박윤아,홍창희 울산대학교 의과대학 1994 울산의대학술지 Vol.3 No.1

From May to July 1993, we observed an epidemic of aseptic meningitis. We performed clinical and virological studies on 174 children with aseptic meningitis who had been admitted to the Department of Pediatrics, Asan Medical Center, from May to July, 1993 The results were as follows; 1) This epidemic of aseptic meningitis was most prevalent in June 1993. The most of the patients were 3 to 6 years old and male to female ratio was 1.6 : 1. 2) The most patients suffered from fever, vomiting, headache, and abdominal pain was noticed in 36% of patients, characteristically. 3) In 7 cases among 10 randomly sampled cases, enterovirus was cultured. Among them, we performed serotyping in 3 cases and Echovirus 9 was isolated.

간세포암의 십이지장침윤에 의한 상부위장관 출혈 1 예

유태현,한광협,박성하,김형길,문영명,한재호,조상호 대한소화기내시경학회 1999 Clinical Endoscopy Vol.19 No.2

Recent advances in both the diagnosis and treatment of hepatocellular carcinoma have improved the prognosis and changed the clinical significance of the recently increasing distant metastases. Distant metastases found after successful treament of the primary lesions are of great clinical significance for the treatment of hepatocellular carcinoma. The duodenum is a rare site of hematogenous metastases or direct invasion from hepatocellular carcinoma. A 23 year old man was admitted with upper gastrointestinal bleeding. He had been diagnosed with hepatocellular carcinoma and treated by a left lobectomy and chemoembolization. The patient was admittted for 12 months after the treatment of the primary tumor. Endoscopic examination revealed a mass in the duodenal bulb that protruded into the lumen. He died due to massive hematemesis. We report on a rare case of hepatocellular carcinoma with duodenal invasion in a 23-year-old male patient.

韓國 在來 山羊의 反芻胃內 微生物의 分離 및 同定에 관한 硏究 : Ⅱ. 反芻胃內 Gram 陽性菌의 分離 및 同定 Ⅱ. Isolation and Identification of Gram Positive Bacteria

朴基文,辛炯泰,姜國熙 成均館大學校 科學技術硏究所 1993 論文集 Vol.44 No.1

This study was undertaken to isolate and identify the gram positive bacterial flora in the rumen of Korean native goat. The results which were obtained in this experiment are as follows : 1. The gram negative cocci which were isolated are Veillonella alcalescens, Megaspharea elsdenii and Quin's Oval. The M-VS medium and PMS medium could be used successfully as a selective medium for the isolation of Veillonella and Megasphaera in the rumen, respectively. 2. The gram negative rods which were isolated are Bacteroides ruminicola subsp. ruminicola, Bacteroides ruminicola subsp. breuis, Bacteroides succinogenes, Fusobacterium necrophorum, Butyriuibrio fibrisoluens, Succinimonas amylolytica, Selenomonas ruminantium and Clostridium clostridiiforme. The CC-NBGT medium and FS medium could be used successfully as a selective medium for the isolation of Bacteroides and Fusobacterium in the rumen, respectively.

어린이 영구치에 나타난 국소적 치아 이형성증의 관리

이형숙,김재문,김신,정태성 大韓小兒齒科學會 2008 大韓小兒齒科學會誌 Vol.35 No.4

국소적 치아 이형성증(Regional Odontodysplasia)은 치아 경조직에 비교적 드물게 나타나는 발육성 장애로 치열궁의 특정 사분악에 국한되어 나타나며 이환치 경조직의 모든 구성요소가 발육 부전이나 석회화 부전을 보인다. 국소적 치아 이형성증에 대한 장기적 치료와 관리를 위해서는 여러 분야에 걸친 체계적 접근이 요구되며,치료 계획은 환자의 저작기능과 심미성의 회복,정상적인 수직고경과 공간의 유지,악골의 정상적인 성장과 이환치의 맹출관리를 도모할 목적으로 수립되어야 한다. 본 증례보고에서는 부산대학교병원 소아치과에서 국소적 치아 이형성증으로 진단받고, 2~5년간 정기적인 관찰을 받아온 5세 8개월~10세 9개월 어린이 3명을 대상으로 그 간의 치료 내용과 치아 발육과정을 검토해 보았다. 관찰 기간 동안 12개 이환치 중 심한 염증과 이형성으로 발거된 1개 치아를 제외한 모든 치아에서 석회화의 진행 또는 치조골 상방으로의 맹출성 이동을 보이긴 하였으나 그 정도와 속도는 개개 치아마다 매우 다양하였다. 그러므로 치료는 악골의 정상 발육과 공간 유지를 도모하고 치아의 조기 상실에 따른 부작용을 차단하기 위해서 이환치에 대하여 최대한으로 보존적인 접근을 하는 것이 추천된다. 또한 치아마다 그 발육정도가 다양하므로 개개 치아의 맹출 관리를 위한 독립적인 치료 계획을 수립하는 것이 바람직할 것으로 판단된다. Regional odontodysplasia is a relatively rare developmental anomaly of dental hard tissue with characteristic clinical. radiographic and histologic features. It requires a continuous and multidisciplinary approaches, and the aim of treatment for these patients should include aiding mastication. improving aesthetics. maintaining normal vertical dimension and space, allowing normal jaw growth and eruptional management of affected teeth. This report describes three cases of regional odontodysplasia with 2-5 years of follow-up. Conservative treatment is chosen to preserve the affected teeth as long as possible, and periodic radiographic and clinical examination was done. During this time, all teeth except one showed progressive development. An interesting finding observed in our cases was that each tooth even in the same person showed different degree of tooth development and eruption rate. Thus, we colcluded that the treatment plan for regional odontodysplasia should be conservative and individualized and based on the assessment of each tooth.

하악골에 발생한 골막 골육종

김태우,김승범,권혁찬,문선재,윤정훈,김형준,차인호,육종인,김진 대한악안면성형재건외과학회 2002 Maxillofacial Plastic Reconstructive Surgery Vol.24 No.1

Periosteal osteosarcoma is a distinct entity of malignant bone tumor with characteristic clinical, morphological, and histological features within the group of juxtacortical osteosarcoma. Periosteal osteosarcoma is predominantly located in the tubular long bones, and extremely rarely involving the jaws. A case of periosteal osteosarcoma of the right mandible is presented. A 27-year-old woman complained of the gingival swelling and bleeding tendency of the right posterior mandible. Clinical examination revealed a reddish brown strawberry-like swelling on the affected mucosa, which measured 1.5㎝×1.5㎝. The tumor was located on the lingual cortex of the mandible and extended into the surrounding soft tissues. Microscopically, the tumor consisted exclusively of atypical chondroblastic cells with a small osteoblastic area. A minimal bone marrow involvement was noted and the adjacent cortex was free of tumor. These findings suggested that the tumor originated from the periosteal cambium layer, which lies between the periosteal fibrous layer and the cortex of mandible.

폐흡충 유약충 및 성충표피의 미세구조

이상문,심태섭,홍성태,이순형 중앙대학교 의과대학 의과학연구소 1981 中央醫大誌 Vol.6 No.4

The teguments of juvenile and adult Paragonimus westermani were observed through scanning and' transmission electron microscopes to outline the ultrastructural differences of the tegument by worm growth and development. The results are as follows. 1. Scale-like spines were observed around oral sucker of juvenile worms irregularly and they remained in adult worms. 2. The tegumental surfaces of juvenile worms consisted of many valleys, cobble stone-like knobs of protoplasmic processes and underdeveloped spines. The tegumental surface was wrinkled greatly and irregularly. 3. The valleys found in the tegument of juvenile worms were not observed in adult worms. And the tips of protoplasmic knobs became wide, therefore, the surface looked flat and smooth in adult worms. The spines of adult worms well protruded due to stretching of the wrinkled tegumental surface of juvenile worms. 4. The findings of transmission electron microscopy correspond well to those of scanning electron microscopy. And it was also found that subtegumental fibrous layer became thick and muscle layers were less compact in adult worms. These findings were regarded as results from the differences of the parasitic location, migration habit and developmental stages between juvenile and adult worms of P. westermani.

SGCI 材料의 Casting 및 磨滅强度에 關한 硏究

김성주,문형태,최익수,노무근 三陟大學校 産業科學技術硏究所 2003 産業科學技術硏究論文集 Vol.8 No.2

In order to collect the basic data for the production of nodular cast iron requiring wear resistance. the mechanical nature such as structure analysis, hardness, and tensile strength were performed on cast sample by changing residual Mg concentration of cast iron at the range of 0∼0.052% and also the wear characteristics were examined through wear test by changing abrasion speed and final load. As a result, the following conclusions were drawn. The wear amount rapidly accelerates to the maximum abrasion sped of 2.3m/sec in a sample without Fe-Si-Mg alloy processing(residual Mg amount; 0%) by increasing the abrasion speed from 1.3m/sec to 2.3m/sec. As the Mg residual Mg contents increases, the ratio of nodular increases while hardness of a sample accelerates and the wear amount decreases. The maximum point moved to the high speed side in a sample with 0.043% residual Mg contents and the wear amount showed the maximum in 3.5m/sec of abrasion speed while a sample with 0.052% residual Mg contents showed the mechanical destruction wear to 4.3m/sec abrasion speed. The more residual Mg contents are in 0.6-l.1m/sec low speed range of abrasion speed, the more wear amount was resulted while the less residual Mg contents were. the less wear amount showed. Oxidation wear occurs at 4.5m/sec of traveling velocity. Since the wear of matrix structure occurs after wear of oxidized substance in friction caused by oxidized substance, the wear amount shows less than 2.3mg/sec traveling velocity. Therefore, as the residual Mg contents increase, the wear amount decreases. Although the wear amount is large since the traveling distance of destruction wear lasts very long. the residual Mg contents are small and the oxidation wear area becomes long in a sample with low hardness. Since the mechanical destruction wear occurs when the traveling &stances reaches to the end, the wear amount results in very small. The scratches appeared due to abrasive wear in mechanical destruction wear with 2.3/sec abrasion speed while it did not show in oxidation wear although the severe wear occurred. The sectional melting appeared in 5.4m/sec of high speed friction since the temperature of contact point increased more than 1000℃. Scratches are less in the area with low load and if load increase, shoving occurs in wear grooves. In the maximum load, the severe cracking phenomenon can be observed.