초급냉(Fe_(1-x)Si_x)_99B_1 합금의 물성

손홍재,강영권,김택기 충남대학교 공업교육연구소 1985 論文集 Vol.8 No.2

The physical properties of(Fe_1-xSi_x)_99B₁alloys fabricated by rapid quenching technique have been studied systemetically by means of a vibrating sample magnetometer, a D.C magnetic hysteresis loop tracer, an eletrical resistance measurement apparatus, a X-ray diffractometer and a vicker's hardness tester. The results are as follows; 1) Saturation magnetization decreases linearly from 210 emu/gr (x=0.03) to 192 emu/ gr (x=0.7) with increasing Si-concentration. 2) Coercive force decreases from 13 Oe (x=0.03) to 6.5 Oe (x=0.06) and then increases to 13.5 Oe (x=0.07) with increasing Si-concentration. 3) Electrical resistivity increases linearly from 57 μΩ-cm to 110 μΩ-cm with increasing Si-concentration and in the rapidly quenched state is about 10% as large as that for the crystallized state(after heated to 1200 K). 4) Vicker's hardness increases from 210 kg/mm²(x=0.03) to 470 kg/mm²(x=0.07) with increasingg Si-concentration. The hardness of the rapidly quenched alloy is less than that of the mother alloy by approximately 80kg/mm².

뇌동맥류 파열 환자에서 증후성 뇌혈관연축의 발생 및 회복에 영향을 미치는 인자들

최석민,석종식,권정택,민병국,황성남,김영백,홍현종 대한신경외과학회 1996 Journal of Korean neurosurgical society Vol.25 No.10

To determine the factors affecting development and recovery of symptomatic vasospasm. the author analysed the results of patients with ruptured intracranial aneurysms treated by nimodipine and prophylactic “triple0H” therapy. From January 1991 to December 1995. 199 patients underwent surgery for ruptured intracerebral aneurysms. Combined hypervolemic hemodilution was initiated at the time of admission. Induced hypertension was added immediately after surgery(aneurysmal neck clipping). All patients received nimodipine intravenously or orally until the 14th day of SAH Sixty patients underwent surgery on Day 0 through 2 after attacks of subarachnoid hemorrhage(Goup A) 105 patients on Day 3 through 14(Group B). and 35 patients after Day 14(Group C). Of 199 patients. 76(38%) patients suffered from symtomatic vasospasm. Symptomatic vasospasm occured in 34% of Group A patients. 33% of Group B patients. and 5% of Group C patients. Symtomatic vasospasm occured more frequently in the older age group. the Fisher group 3 and Hunt & Hess grades 3, 4 and 5 groups. Of 76 patients who suffered from symptomatic vasospasm. 47(62%) patients recovered completely. The author analysed the relationship between recovery rate and sex, age. Hunt & Hess agrde and Fisher group among these 76 patients. Recovery rates between these groups were not significantly different. Based on this experience the author believes that Hunt-Hess grade. Fisher group and age are important factors affecting symptomatic vasospasm development.

復合材料 連結 部位를 갖는 엔진 마운트 設計에 關한 硏究

최원종,김권진,오인택,임동준,홍영길,황명신 한국항공대학교 1993 論文集 Vol.31 No.-

본 논문에서는 초경량 항공기의 엔진 마운트 구조물에 대한 유한요소 해석을 수행하였으며, 구조의 안전성 확보에 중요한 영향을 주는 부분인 복합재료 동체와 엔진 마운트 간의 연결 부위에 대한 해석을 위해 유한요소 프로그램을 작성하였다. 본 연구에 의해 작성된 유한요소 프로그램의 신뢰성을 확인하기 위해 실제로 시편 제작 실험을 실시하여 실험치와 해석치를 비교 검토하였다. The finite element analysis was performed on the ULM's engine mount to verify the structural safety Result showed that proposed engine mount structure has a large margine of safety. Strains and stresses in the vicinity of the joint between a composite fuselage and a metallic engine mount were calculated by the finite element analysis program. Numerical results from the model were compared with the test results. Good agreement was found between experiment and model results.

Renewable Monomer Based on Rosin in Photoinitiated Radical Polymerization

Hong, Young Taik,Shim, Sang Yeon 한국유화학회 2000 한국응용과학기술학회지 Vol.17 No.3

Rosin moeity-containing monomer was prepared by the reaction of abietic acid with 2-hydroxyethyl methacrylate in tetrahydrofuran(THF) using diethyl azodicarboxylate as a catalyst. This new monomer was photo-polymerized to give thin films in the presence of a radical type initiator. The rate of photo-polymerization and amount of cured polymer were determined using the residual yield method. A thermogravimetric analysis of the cured polymer showed that the film was stable up to 170oC, at which point the polymer film has lost 10 wt % of its weight.

디아민 변화에 따른 폴리이미드 필름의 물리적 특성과 흡습률 분석

홍영택(Young Taik Hong),박윤준(Yun Jun Park),유덕만(Duk Man Yu),최종호(Jong Ho Choi),안정호(Jeong Ho Ahn) 한국고분자학회 2012 폴리머 Vol.36 No.3

Pyromellitic dianhydride(PMDA), 3,3`-4,4`-benzopenonetetracarboxylic dianhydride(BPDA) 그리고 pphenylenediamine(p-PDA)와 함께 1,4-bis(4-aminophenoxy)benzene(1,4-APB)와 2,2-bis[4-(4-aminophenoxy) phenyl]hexafluoropropane(HFBAPP)를 각각 이용하여 폴리아믹산을 합성하였고, 이를 열적 이미드화 공정을 통하여 폴리이미드 필름을 제조하였다. 제조된 필름은 퓨리에 변환 적외선 분광기(FTIR), 열 중량 분석기(TGA), 열 기계 분석 기(TMA), 동·역학적 거동 분석기(DMA), 그리고 만능 인장 시험기(UTM) 등을 이용하여 화학 구조 및 열적·기계적 특성을 조사하였다. 1,4-APB와 HFBAPP의 조성이 증가함에 따라 열적·기계적 물성과 흡습률이 낮아지는 경향을 나타내었고, 동박과 비슷한 열팽창계수(CTE)를 가진 폴리이미드 필름의 경우 HFBAPP를 이용한 필름이 1,4-APB를 이용한 필름보다 향상된 열적 특성과 낮은 흡습률 결과를 나타내었다. 이와 같이 본 연구에서 합성된 폴리이미드 필름은 유연성 회로 기판의 flexible copper clad laminates(FCCL)를 위한 기본 필름으로 적용할 수 있을 것으로 판단된다. Poly(amic acid)s were successfully synthesized from 1,4-bis(4-aminophenoxy)benzene (1,4-APB) or 2,2-bis[4-(4-aminophenoxy)phenyl]hexafluoropropane (HFBAPP) with pyromellitic dianhydride (PMDA), 3,3`-4,4`- benzopenonetetracarboxylic dianhydride (BPDA) and p-phenylenediamine (p-PDA) and then they were effectively converted into polyimide films by thermal imidization. The chemical structure and thermo-mechanical properties of polyimide films were examined using Fourier transform infrared spectroscopy (FTIR), thermo-gravimetric analyzer (TGA), thermo-mechanical analyzer, dynamic mechanical analyzer (DMA) and universal tensile machine (UTM). The moisture absorption, thermal and mechanical properties of polyimide films decreased with increasing the amount of 1,4-APB and HFBAPP. The polyimide films using HFBAPP showed lower properties than that of 1,4-APB at the same ratio, but it displayed better thermal properties and lower moisture absorption at the similar coefficient of thermal expansion (CTE) with a copper. On the basis of our finding, it is concluded that 4- component polyimide films could be utilized for base films for flexible copper clad laminates (FCCL) of flexible printed circuit boards.

자궁내 장치를 동반한 노인에서 급성 괴사성자궁근염 (Acute Gangrenous Myometritis)에 의한 자궁천공

국일영 ( Ill Young Kook ),천근영 ( Keun Young Cheon ),정재은 ( Jae Eun Chung ),김미란 ( Mee Ran Kim ),임용택 ( Young Taik Lim ),배석년 ( Seog Nyeon Bae ),김진홍 ( Jin Hong Kim ) 대한산부인과학회 2006 Obstetrics & Gynecology Science Vol.49 No.3

Chemoprevention of Helicobacter pylori-associated Gastric Carcinogenesis in a Mouse Model; Is It Possible?

Hahm, Ki-Baik,Song, Young-Joon,Oh, Tae-Young,Lee, Jeong-Sang,Surh, Young-Joon,Kim, Young-Bae,Yoo, Byung-Moo,Kim, Jin-Hong,Ha, Sang-Uk,Nahm, Ki-Taik,Kim, Myung-Wook,Kim, Dae-Yong,Cho, Sung-Won Korean Society for Biochemistry and Molecular Biol 2003 Journal of biochemistry and molecular biology Vol.36 No.1

Although debates still exist whether Helicobacter pylori infection is really class I carcinogen or not, H. pylori has been known to provoke precancerous lesions like gastric adenoma and chronic atrophic gastritis with intestinal metaplasia as well as gastric cancer. Chronic persistent, uncontrolled gastric inflammations are possible basis for ensuing gastric carcinogenesis and H. pylori infection increased COX-2 expressions, which might be the one of the mechanisms leading to gastric cancer. To know the implication of long-term treatment of antiinflammatory drugs, rebamipide or nimesulide, on H. pylori-associated gastric carcinogenesis, we infected C57BL/6 mice with H. pylori, especially after MNU administration to promote carcinogenesis and the effects of the long-term administration of rebamipide or nimesulide were evaluated. C57BL/6 mice were sacrificed 50 weeks after H. pylori infection. Colonization rates of H. pylori, degree of gastric inflammation and other pathological changes including atrophic gastritis and metaplasia, serum levels and mRNA transcripts of various mouse cytokines and chemokines, and NF-${\kappa}B$ binding activities, and finally the presence of gastric adenocarcinoma were compared between H. pylori infected group (HP), and H. pylori infected group administered with long-term rebamipide containing pellet diets (HPR) or nimesulide mixed pellets (HPN). Gastric mucosal expressions of ICAM-1, HCAM, MMP, and transcriptional regulations of NF-${\kappa}B$ binding were all significantly decreased in HPR group than in HP group. Multi-probe RNase protection assay showed the significantly decreased mRNA levels of apoptosis related genes and various cytokines genes like IFN-$\gamma$, RANTES, TNF-$\alpha$, TNFR p75, IL-$1{\beta}$ in HPR group. In the experiment designed to provoke gastric cancer through MNU treatment with H. pylori infection, the incidence of gastric carcinoma was not changed between HP and HPR group, but significantly decreased in HPN group, suggesting the chemoprevention of H. pylori-associated gastric carcinogenesis by COX-2 inhibition. Long-term administration of antiinflammatory drugs should be considered in the treatment of H. pylori since they showed the molecular and biologic advantages with possible chemopreventive effect against H. pylori-associated gastric carcinogenesis. If the final concrete proof showing the causal relationship between H. pylori infection and gastric carcinogenesis could be obtained, that will shed new light on chemoprevention of gastric cancer, that is, that gastric/cancer could be prevented through either the eradication of H. pylori or lessening the inflammation provoked by H. pylori infection in high risk group.

Chemoprevention of Helicobacter pylori-associated Gastric Carcinogenesis in a Mouse Model : Is It Possible?

Hahm, Ki Baik,Song, Young Joon,Oh, Tae Young,Lee, Jeong Sang,Surh, Young-Joon,Kim Young Bae,Yoo, Byung Moo,Kim, Jin Hong,Han, Sang Uk,Nahm, Ki Taik,Kim, Myung-Wook,Kim, Dae Yong,Cho, Sung Won 한국생화학분자생물학회 2003 BMB Reports Vol.36 No.1

Although debates still exist whether Helicobacter pylory infection is really class I carcinigen or not, H. pylori has been known to provoke precancerous lesions like gastric adenoma and chronic atrophic gastritis with intestinal metaplasia as well as gastric cancer, Chronic persistent, uncontrolled gastric inflammations are possible basis for ensuing gastric carcinogenesis and H. pylori infection increase COX-2 expressions, which might be the one of the mechanisms leading to gastric cancer. To know the implication of long-term treatment of antiinflammatory drugs, rebamipide or nimesulide, on H. pylori-associated gastric carcinogenesis, we infected C57BL/6 mice with H. pylori, expecially after MNU administration to promote carcinogenesis and the effects of the long-term administration of rebamipide or nimesulide were eva,uated. C57BL/6 mice werre sacrificed 50 weeks after H. pylori infection. Colonization rates of H.pylory, degree of gastric inflammation and other pathological changes including atrophic gastitis and metaplasia, serum levels and mRNA transcripts of various mouse cytoknes and chemokines, and NF-κ]B binding activities, and finally the presence of gastric adenocarcinoma were compared between H. pylori infected group (HP), and H.pylori infected group administrated with long-term rebamipide containing pellet diets (HPR) or nimesulide mixed pellets (HPN). Gastric mucosal expressions of ICAM-1, HCAM, MMP, and transcriptional regulations of Nf-κB binding were all significantly decreased in HPR group than in HP group. Multi-probe RNase protection assay showed the significantly decreased mRNA levels of apoptosis related genes and various cytokines genes like IFN-r, RANTES, TNF-α, TNFR p75, IL-1β in HPR group. In the experiment designed to provoke gastric cancer through MNU treatment with H.pylori infection, the incidence of gastric carcinoma was not changed between HP and HPR group, but significantly decreased in HPN group, suggesting the chemoprevention of H. pylori-associated gastric carcinogenesis by COX-2 inhibition. Long-term administration of antiinfalmmatory drugs should be considered in the treatment of H. pylori since they showed the molecular and biologic advantages with possible chemopreventive effect against H. pylori-associated gastric carcinogenesis. If the final concrete proof showing the causal relationship between H. pylori infection and gastric carcinogenesis. If the final concrete proof showing the causal relationship between H. pylori infection and gastric carcinogenesis could be obtained, that will shed new light on chemoprevention of gastirc cancer, that is, that gastric cancer could be prevented through either the eradication of H. pylori or lessening the inflammation provoked by H. pylori infection in high risk group.

맹장 천공 및 재발성 장피누공의 임상경과를 보인 Bechcet씨병 1예

홍영종,박성준,박성일,장선택,박용욱,송계용 중앙대부설한국의과학연구소 1989 한국의과학 Vol.21 No.3

맥락렬의 해부학적 구조 및 미세수술 접근법에 대한 고찰

홍현종,권정택,박관,이원복,김영백,민병국,황성남,최덕영,석종식 대한신경외과학회 1996 Journal of Korean neurosurgical society Vol.25 No.5

The authors had studied the microsurgical anatomy of the choroidal fissure and the operative approaches directed through the fissure. In this study. eight formalin fixed cadaveric hemispheres were examined. In four hemispheres. the intracranial vessels were perfused with colored silicone latex. The choroidal fissure is divided into three portions : (a) body portion. (b) atrial portion. and (c) temporal portion. Dissection through the body portion of the choroidal fissure exposes the velum interpositum. internal cerebral vein. and third ventricle. The quadrigeminal cistern. pineal region, and posterior part of the ambient cistern can be exposed through the atrial portion of the choroidal fissure. Opening through the temporal portion of the choroidal fissure exposes the structures in the ambient cistern. which include the basal vein. posterior cerebral artery. anterior and lateral posterior choroidal arteries, and hippocampal formation. This study provides valuable knowledges of microsurgical approaches to the third ventricle and basal cistern by demonstrating the neural and vascular relationship around the choroidal fissure.