Effect of Ti Addition on the Microstructure and High-Temperature Oxidation Property of AlCoCrFeNi High-Entropy Alloy

Gi‑Su Ham,Young‑Kyun Kim,Young Sang Na,Kee‑Ahn Lee 대한금속·재료학회 2021 METALS AND MATERIALS International Vol.27 No.1

This study investigated the effect of Ti addition on microstructure and high-temperature oxidation property of AlCoCrFeNihigh-entropy alloy. Ti content was controlled at 0 at% and 1 at%. The two alloys were found to have BCC single phase, andthe average grain sizes of Ti0.0 and Ti1.0 were 47.3 μm and 49.7 μm, respectively, showing similarity. The EDS mappingof the inside of grains found that both alloys were characterized to be divided into Al-Ni element rich region and Cr–Feelement rich region. As a result of high-temperature oxidation test at 1100 °C, oxidation weight gains were measured atTi0.0: 0.75 mg/cm2 and Ti1.0: 0.17 mg/cm2, respectively. The results indicate that Ti addition largely improved high temperatureoxidation resistance of AlCoCrFeNi HEA. Ti1.0 alloy, in particular, showed remarkably more excellent 1100 °Chigh-temperature oxidation resistance than other previously reported major ones such as NiCrAl and FeCrAl. In the surfaceand cross-section observations after oxidation tests, both alloys were found to have Al2O3oxides mostly. While the Ti0.0material was observed to have Al2O3spallation macroscopically, the Ti1.0 alloy showed Al2O3spallation only in some localareas. In addition, a unique result was found in AlCoCrFeNiTix(x=0,1) alloy that BCC → FCC phase transformation was accelerated,and FCC phase layer was formed in the surficial area where Al element had been depleted due to high-temperatureoxidation. Moreover, as Ti was added, the thickness of FCC layer induced by high-temperature oxidation decreased. Basedon the results, it was also discussed on how to improve the high-temperature oxidation resistance of AlCoCrFeNiTixHEA.

제주 성상 S/S MTr #1 행원 풍력단지 전압해석

김상준(Sang-Jun Kim),조민호(Min-Ho Cho),윤기갑(Gi-Gab Yoon),장상옥(Sang-Ok Jang),안정식(Jeong-Shik Ahn) 대한전기학회 2003 대한전기학회 학술대회 논문집 Vol.2003 No.11

소포체 스트레스에 의한 대식세포의 세포사멸 : caspase 11의 잠재적 역할 a potential implication of caspase 11

정상원,김용찬,이혜영,백상기,김영상,강광일 충남대학교 생물공학연구소 2004 생물공학연구지 Vol.10 No.1

Apoptosis is caused by a set of previously latent proteases, the caspases, which cleave several hundred cellular substrates. It has been established that there are two basic signaling pathways to caspases activation. One is initiated by engagement of cell surface death receptors (extrinsic pathway). The other is provoked by perturbation of the mitochondrial membrane promoted by physical or chemical stress agents (intrinsic pathway). Recent studies point to the endoplasmic reticulum (ER) as a third subcellular compartment implicated in apoptotic cell death. The ER regulates protein synthesis, protein folding and trafficking, cellular responses to stress and intracellular calcium (Ca^(++)) levels. Alterations in Ca^(++) homeostasis and accumulation of misfolded proteins in the ER cause ER stress that ultimately leads to apoptotic cell death. Prolonged ER stress is linked to the pathogenesis of several different neurodegenerative disorders. However, ER stress-mediated cell death pathway in macrophage has not been studied well. Here, we demonstrate evidence for the thapsigargin-induced cell death and the potential contribution of caspase-11 which could be induced by ER stress in macrophage.

녹동균 세포외막 단백질 백신 CFC-1-101의 안정성 및 면역원성 검토 : 임상 제 Ⅰ/Ⅱa상 시험

장인진,김익상,유경상,임동석,김형기,신상구,장우현,박완제,이나경,정상보,안동호,조양제,안보영,이윤하,김영지,남성우,김현수 대한감염학회 1998 감염 Vol.30 No.3

목적 : 제일제당에서는 녹농균의 세포외막 단밸질을 유효성분으로 하는 백신인 CFC-101을 개발하였으며, 동물시험에서 이 백신의 안전성과 유효성을 입증하였다. 본 연구에서는 이 녹농균 백신의 인체에 대한 안전성과 면역원성을 평가하는 동시에 인체 접종시의 최적 투여 용량을 결정하기 위하여 제 I/Ⅱa상 임상시험을 수행하였다. 방법 : 건강한 성인 남자를 피험자로 선별하여 각 용량군에 백신투여자 6명, 위약투여자 2명을 배정하였다. 백신 투여군은 0.25mg, 0.5mg 또는 1.0mg 용량의 녹농균 백신을 7일 간격으로 3회에 걸쳐 근육주사 하였으며, 위약 투여군에게는 세포외막 단백질을 제외한 동일한 성분을 투여하였다. 백신접종 후 국소적 또는 전신적인 반응의 발생여부를 관찰하고, 혈액시료를 체취하여 백신의 역가와 유효성을 검정하였다. 결과 : 녹농균 백신 CFC-101은 모든 접종자에서 양호한 내약성을 보였다. 또한 0.5mg 과 1.0mg 백신 투여군에서는 100%의 항체양전율을 나타내었다. 생성된 항체는 녹농균 세포외막단백질에 특이성을 보였고, 녹농균 감염에 대해 방어효능이 있었다. 결론 : 이와같은 결과로부터 이 녹농균 백신은 인체에 안전하게 투여할 수 있으며, 높은 항체 생성능으로 감염방어 효능을 보이고 0.5mg과 1.0mg이 최적용량인 것으로 판단되었다. Background : We developed a Pseudomonas aeruginosa outer membrane protein(OMP) vaccine CFC-101, and the prophylactic efficacy of which has been demonstrated in animal models. In order to evaluate the safety and immunogenicity of the P. aeruginosa vaccine, we carried out a phase I/Ⅱa clinical trial in healthy male volunteers. Methods : Groups of eight volunteers, including two placebo subjects, were vaccinated intramuscularly with three doses of 0.25, 0.5 or 1.0 mg of the vaccine at one week intervals. Sings of systemic and local reactions observed after vaccination were recorded for each vaccinee for 5 days. Physical examinations were performed on days 0, 1, 7, 8, 14, 15, 21, and 42, and clinical laboratory tests were done on days 0, 3, and 21. Blood samples for assay of serum antibody levels were obtained up to 42 days after the first vaccination. Results : The vaccine was generally well tolerated by all vaccinees, showing no significant side effects. In the three dosage groups, all vaccinees, except one receiving the 0.25 mg dose, showed significant elevation in serum IgG antibody titers against the vaccine proteins, indicating 100% seroconversion in 0.5 and 1.0 mg groups. The human antibodies induced by the vaccine were specific for P. aeruginosa OMPs, as confirmed by western blot analysis and immunoprecipitation assays. The capacity of the human antisera to enhance opsonophagocytic killing activity by polymorphonuclear leukocytes and to confer protection against P. aeruginosa infections indicates that the antibodies elicited by the vaccine have protective efficacy. Conclusion : We conclude that the P. aeruginosa OMP vaccine is safe and effective for human use and its optimal dose to be 0.5 or 1.0 mg.

골다공증의 위험인자 : 아산시 지역 주민을 대상으로

김용배,장원기,황보영,김화성,안규동,이병국,이용진,이남수,이상건,이상범,이상우,이선정,이성수 순천향대학교 2006 Journal of Soonchunhyang Medical Science Vol.12 No.1

Objective : As the average lifespan of human increases, osteoporosis and osteoporosis-related fractures have become major health care problems. Despite recent advances in medical treatment, few studies have assessed the recognition of osteoporosis in general adults. This study examined the recognition of osteoporosis and analyzed the relating factors. Method : A population-based sample of 1086 adults in Asan-city, Korea was investigated with questionnaires and height, weight, Information regarding the general characteristics(gender, age, economic state), lifestylef exercise, smoking, alcohol),medical history(progestin, GH, steroid, calcitonin, PTH), demographic parameter, obesity, stress, and family history was collected through an interview using a structural questionnaire. The level of obesity was measured by the body mass index(BMI). BMD(Bone mineral density) at the lumbar spine and femoral neck was measured by dual energy X-ray absorptiometry. Osteoporosis was considered to be T-score below -2.5. Results : The prevalence of osteoporosis increased progressively with age, decreased with BMI and predominant in women by the result of x^(2) -test, T-test. Age, weight, BMI were significantly correlated with osteoporosis by the result of Pearson correlation ana1ysis(P<0.05). And age, gender, BMI, family history of osteoporosis were proved to be significant risk factors of osteoporosis by the result of multiple logistic regression(P<0.05). Conclusion : These results suggest that age, gender, BMI might be the most important risk factors of osteoporosis. And the history taking about family history of osteoporosis is helpful for diagnosing osteoporosis.

보조자극분자를 이용한 암치료

장미라,윤희령,성인옥,정상원,김용찬,손정희,이혜영,강광일,백상기,김영상 충남대학교 생물공학연구소 2002 생물공학연구지 Vol.8 No.1

Tumor cells express tumor-associated antigen which can be target to the cytotoxic Tlymphocytes. CTL precursor activation requires antigen recognition and cytokine help from Th cells. In this pathway, the cross-presentation mechanism, professional antigen presenting cells first pick up tumor antigen and present the antigen to Th cells. Another pathway is to activate CTL precursor by the direct priming. The tumor cells, however, lack costimulatory signal, which is required for full activation. The lymphocytes recognized specific antigen without costimulatory signal resulted in anergy. Tumor cells engineered to express the costimulatory molecules are better immunogen and induce antitumor immunity. We will discuss the recent progress in tumor therapy using the costimulatory molecules on the basis of the direct priming mechanism.

초음파 가이드를 통한 맥락막상강출혈의 치료

이기헌,유재호,김태원,이상준,김신동 고신대학교 의과대학 2009 고신대학교 의과대학 학술지 Vol.24 No.1

Purpose : Intraoperative suprachoroidal hemorrhage is one of the most serious complications. We report a case of suprachoroidal hemorrhage during phacoemulsification surgery, was managed properly. Methods : Suprachoroidal hemorrhage occurred during phacoemulsificaiton in other hospital. The patient was referred to our department immediately after closing the surgical wound. On initial examination, iris and vitreous were prolapsed through surgical wound. Ciliary body was closely place to anterior chamber, and retina was not visible. Results : Prolapased ocular tissue were reduced by emergency operation. We controlled the patient’s intraocular pressure and inflammation. Ultrasonography was repeatedly performed to check the degree of liquefaction of suprachoroidal hemorrhage. After 9 days of suprachoroidal hemorrhage onset, vitrectomy and drainage through sclera was performed. Postoperative state was stable with successful removal of suprachoroidal hemorrhage. After 2 weeks of secondary operation, retinal detachment has occurred on nasal retinal area, so we performed scleral buckling and endolaser photocoagulation. After 6 months, retina was attached well and intraocular pressure was in normal range. Conclusion : In suprachoroidal hemorrhage, drainage of suprachoroidal hemorrhage after liquefaction of thrombi is effective. After successful drainage, postoperative complications may accompany such as retinal detachment or elevation of intraocular pressure. 목적 : 술중 발생하는 맥락막상 출혈은 매우 심각한 합병증이다. 저자는 수정체 유화술 중에 발생한 맥락막상 출혈을 적절히 대처한 증례를 보고하는 바이다. 대상과 방법 : 수정체 유화술 중 발생한 맥락막상강 출혈환자가 수술창을 봉합 후 즉시 본원으로 전원되었다. 초진시 홍채와 유리체가 수술창을 통해 탈출되어 있었으며, 전방을 통해 모양체가 확인되었으나, 망막은 보이지 않았다. 탈출된 안구내 조직을 응급수술을 통해 복원 후 환자의 안압과 염증을 조절하였다. 초음파를 반복적으로 실시하여 맥락막상 출혈의 액화 정도를 확인하였으며, 출혈 9일 후 유리체 절제술과 공막을 통한 배액술을 시행하였다. 결과 : 맥락막상 출혈이 성공적으로 제거되었으며 술 후 상태는 안정적이었다. 수술 2주 후 비측 망막 박리가 발생하여 공막돌륭술과 안구내 삽관 레이저술을 시행하였다. 6개월 후 망막은 잘 붙어있었으며, 안압은 정상 범위를 유지하였다. 결론 : 맥락막상 출혈의 경우 출혈의 배액 시기를 결정하는 것이 어렵지만, 규칙적인 초음파를 통해 배액술의 시기를 결정할 수 있다. 또한 맥락막상강 출혈의 성공적인 배액 이후에도 망막박리 및 안압상승과 같은 합병증의 동반에 대해 유념해야한다.

간세포성 암종과 담관암종에서 Glutathione S-Transferase π의 면역조직화학적 발현

한상영,손영기,이종훈,박희승,노명환,최석렬,최홍조,허기영 大韓消化器病學會 1998 大韓消化器病學會誌 Vol.31 No.1

韓國詩의 純粹性과 參與性에 關한 硏究 : 韓國 現代詩를 中心으로

成耆兆 단국대학교 대학원 1980 學術論叢 Vol.4 No.-

The contemporary poetry is an another world created through the poets. For an organized reality of life or nature potencially exists as a material of poem, out it is not a poem itself. The contemporary poetry which is a different world created through the poets, a cryst allization which is accomplished through their own experiments, must be dealt with a very pure crystallization composured through media, letters, and such a poem must be written in prder to contribute human beings and to lead us into the truth. Poetry is accomplished by a poet's wise views and developed sensibility, based on our atmost aims; the ideal and mental values of human beings. So far as a poetry is intended to the explanation of whole life, even it is created by a poet's sensibility, both of scientific and moral method muet not be ignored at all for the poetry world. Here, the sensual function, a manifestation of ethics and consciousness is availably included the in intelligence and rationality of the poets. So a true poem mustbe based on a real poetical thought which is flourished from the poet's phlosophy, intelligence and emotion, and a poem is able to called as a poet's recomposured thought. It is ture that a poem has to beincluded the poetical truth becasseit exists for the human beings bymaking the original meaning of lfe renew and reforming the individuals through its rhythmical poetiic dictions. The poetical truth, an art's value must be come throughim pressions, and only an arrangement of letters, at the same time, is nothing but a vacant monologue. The traditional essence of poetry-accepted, expressed and stimulated by sensibility-is composured various elements including the intelligence and rationality. Among the various elements, only two of them (one is the pure function of he contmeporary poetry, and the other is the social function of the contemporary poet) are dealt with inthis thesis: in the one, the rhythmical instructional and pictorial elements of poetry are studied, and in the other, every potencial questions of pure and participating poetry are studied with many examples of the Korean contemporary poetry; by explaining the poetical and refusal elements on the participation because the social function is required the poetical participation to society. We can easily appreciate that the poems composured by the poets, who adhete to only the purity of Korean poetry ad turn away their attentions to the reality used to be intended to the very idolenee and at last lost theiraffections from the leader becauseit is ignored the the poets' philosophy, and that the poets who try to proted participating poetry mostly fall into a vacant realm of thought by emphasizing the non-elemental essences which are apart from the original literary essences. In the contemporary poetry of Korea, it is true that there is a profound wall and sturggle between the purity and participation of poetry. It is ture that a well composured lyric poem alone has its own poetic value, and a participating poetry is also valuable with itself. The more variety in literature, the better. And a poem becomes great only when it is appeared with various meaning. Here we are really acquired poets and poems in which the purity with the aesthetic values and theprofound philo ophical though of impressions would be accomplished in the field of Korean contemporary poetry.

死刑制度에 關한 小考

成基宅 중앙대학교 법학대학 1973 法政論叢 Vol.17 No.1