Corrosion and Oxidation Resistance Behaviors of Ta-Containing Low Alloying Zirconium

Il‑Hyun Kim,Yang‑Il Jung,Byoung‑Kwon Choi,Hyun‑Gil Kim,Jae‑Il Jang 대한금속·재료학회 2021 METALS AND MATERIALS International Vol.27 No.8

Zirconium alloys are widely used to fabricate nuclear fuel claddings, and thus is desirable to improve the resistance of suchalloys to corrosion and structural instability. In this study, Ta was used as an alloying element to improve the corrosion andoxidation resistance of zirconium alloys. The model alloy (TaZL) contained 0.03 wt% Ta and other elements with a proportionof less than 1 wt% in total (0.1 wt% Nb, 0.4 wt% Fe, 0.2 wt% Cr) in a zirconium base. The corrosion test involving pressurizedwater at 360 °C and oxidation test involving steam at 1200 °C indicated that TaZL exhibited the lowest weight gains amongthose of compared conventional and advanced Zr alloys. The corrosion and oxidation resistances of TaZL were respectivelyimproved by 4 and 1.5 times compared to the corresponding values of Zircaloy-4. The microstructures of the oxide formedon TaZL were columnar along the oxide growth direction and did not change from columnar to equiaxed, which resulted inthe high resistance of the alloy to corrosion and oxidation.

골다공증에 의한 골절의 수술적 치료

최일용,김병훈 한양대학교 의과대학 2002 한양의대 학술지 Vol.22 No.1

With the increase in life span and old populations, 'osteoporosis' has attracted so much public attention as well as medical society's. Osteoporosis is a systematic disease that fragility and susceptibility of fracture increase as a result of low bone density and embarrassment of bony microstructure. This disease becomes increasingly apparent in women after the menopause period and sharply become severe in old ages. This condition is observed in men as well, though it seems less severe than women. Fracture mainly appears in the spine, in the femoral neck and intertrochanteric area, also in the distal radius. It also causes pain, economic loss, physical discomfort, deteriorated life style. Here we will discuss operative treatment on fracture caused by osteoporosis and methods to enhance fixation in osteoporotic patients.

CdS 광도전막의 제조 및 그 응용

최병진,박욱동,이우일,김기완 경북대학교 센서기술연구소 1991 센서技術學術大會論文集 Vol.2 No.1

The Polycrystallized CdS films have been fabricated at the substrate temperature above 200℃ by thermal evaporation method. When the CdS films were annealed at the temperature higher than 400℃, the dark resistivity was increased. From the photoconductive properties of CdS films under 50~1500uW/cm^(2) illumination, the maximum values of I_(p)/I_(d) ratio and photosensitivity were 60dB and 0.82, respectively. The optical properties of CdS films were measured by spectrometer, the optical band gap of CdS film was different with heat treatment, These results show that this evaporated CdS films are expected to be used as photoconductive cells or photoelectric sensors.

4-nitro-N-(triphenyl phosphoranylidene)의 전기화학적 환원에 관한 연구

최창진,김일광,이기학,전병영,김봉원 圓光大學校 基礎自然科學硏究所 1984 基礎科學硏究誌 Vol.3 No.2

The electrochemical reduction of 4-nitro-N-(triphenyl-phosphoranylidene) in nonaqueous media has been examined by polarography, cyclic voltammetry and controlled-potential coulometry. The reduction of 4-nitro-N-(triphenylphosphoranylidene) proceeds by a one electron-transfer to form anion radical which undergoes both protonation and a second one electron reduction followed by cleavage of a phosphorous-phenyl bond was also observed after reduction of triphenylphosphine oxide which is one of the major products of the chemical reaction which follow the primary electrode process.

1-Phenylindole Ester류의 합성과 반응성 연구

崔舜圭,金兪瑛,兪丙國,李龍均,鄭大一 東亞大學校附設基礎科學硏究所 1993 基礎科學硏究論文集 Vol.10 No.1

일반적인 dienophile에 대한 pyrrole의 반응은 pyrrole이 diene system으로 작용된 [4+2] 고리부가반응과 pyrrole의 α-탄소 위치에 부가되는 Michael형태의 반응이 알려져 있다.

2D영상에서의 CONVEX HULL처리를 위한 SPLINE활용 연구

이병일,서재현,최흥국 인제대학교 1997 仁濟論叢 Vol.13 No.1

본 논문은 2D image에서의 object boundary representation을 위한 여러 가지 알고리즘중[6] convex hull 처리를 위해 스플라인(spline)을 도입한 방법을 제시하였다. 연속적인 점들에 대한 곡선의 추출은 각 점에서의 기울기를 일차 미분을 통해 연속적으로 처리하고, 그 점들을 이용해서 boundary region을 위한 point를 찾아낸 다음, 스플라인을 활용하여 boundary region을 추출해내는 것이다. In this paper, I studied about spline curve for convex hull at 2D image. There are many algorithm of boundary representation, but spline is new challenge for boundary representation and tracing. The purpose of this paper is to apply spline to convex hull at 2D image. The abstrction of curve about continuous point is treated successive by diferentiation of first degree of each point. It can be found a traced boundary region by this algorithm. After applied this algorithm, it should be developed to 3D image with sliced 2D image. Because 3D function needs spline interpolation for representation of cubic delineation and reconstruction. In the x-ray the image which is discontinuous fur noise and its characteristic feature, would be applied to find visible boundary and its segmentation line.

난소암에서 CA125의 임상적 의의

윤병일,김수녕,손인숙,유연웅,최원석 건국대학교 의과학연구소 2000 건국의과학학술지 Vol.10 No.-

The concentration of the tumor marker CA125 in serum from patients with ovarian tumor was measured to define the usefulness of them in differentiating malignant ovarian tumor from benign ovarian mass. In the study of 105 patients with gynecologic neoplasm, of whom 38 were myoma uteri, 42 benign ovarian tumor, and 25 ovarian cancer, the level of serum CA125 were measured. CA125 was greater than 35 U/ml in 2.6% of myoma uteri, in 2.4% of benign ovarian tumors and 68.0% of ovarian cancers. Using a cut-off level of 35 U/ml, the results can be characterized by a 68.0% of sensitivity and 97.5% of specificity in detecting an ovarian cancer. Among 25 patients with ovarian cancer, 11 of 14 (78.6%) patients with serous cystadenocarcinoma, 4 of 6 (66.7%) patients with mucinous cystadenocarcinoma and 2 of 5 (40.0%) patients with endometrioid carcinoma had CA125 values greater than 35 U/ml. In relation to a higher tumor stage, there was an increasing incidence of elevated levels of CA125. As a result, it is likely that the measurement of CA125 is useful for early diagnosis of ovarian cancer.

Compass 연산자를 이용한 Edge의 방향정보 표현

이병일,최현주,최흥국,전순미 인제대학교 1998 仁濟論叢 Vol.14 No.1

에지(edge)의 검출은 영상처리를 하기 위한 전처리 단계로서 중요하고도 기초가 되는 부분이다. Compass 기울기 연산자는 방향에 따른 마스크를 사용하여 에지를 검출하여 주는데, 본 논문에서는 이러한 Compass 기울기 연산자를 이용하여 찾아지는 에지를 방향에 따라서 색상을 지정하여 표현함으로써 에지 정보의 방향성을 시 각화하도록 하였다. 예제 이미지는 임의의 타원으로 구성된 실험용 이미지와 다른 하나는 쥐와 운동 신경조직을 현미경으로 확대하여 본 이미지이다. Digital Image Processing is divided into two branches. One is Improvement of Image Information which helps human beings to understand image, and another is Image Data Analysis which helps the machine to have cognizance of image. Edge Detection is indispensable part to apply two branches, for it is basic application. Edge Detection is important and basic preprocess at Image Processing. Edge can be found by Compass operator as direction with 3×3 Masks. Compass operator has 8 element to be compared. Each has an information about direction of an edge. To visualize edge information, We propose the method of edge detection as direction showed by color. First, We had experiment on 4-Direction, then on 8-Direction. 8-Direction 8-Color method was better than 4-Direction 4-Color method, for Compass operator had 8 elements. Result Image shows the color which has direction information.

洛東江 河口周邊의 防災對策에 관한 基礎的인 硏究

민일규,김원규,최병습,박상길,김가현 釜山大學校生産技術硏究所 1996 生産技術硏究所論文集 Vol.51 No.-

波浪과 흐름이 共存하는 大河川 河口部인 洛東江 河口域에서 洛東江 河口둑을 基点으로 波浪, 흐름, 地形變動, 潮流, 洪水位等을 評價基準으로 하여 災害에 대한 基本的인 評價를 實施했다. 波浪, 潮流, 洪水位等이 水位上昇을 透發시켜 周邊地域을 浸水시킬 수 있는 危險性의 與否를 實測과 數値計算을 통하여 實施하였다. 地形變動은 實測만을 통하여 地形變動率을 調査하였다. 資料를 分析한 結果 洛東江 河口地域은 波浪, 흐름과 波浪이 共存하는 領域으로 區分된다. 數値計算結果에 의하면 河口部에서의 來襲波高가 直接 河口둑 水門과 주변構造物에 미치는 影響은 크지 않았다. 또한, 3次元 波高分布를 볼 때 河口 水路를 따라서 거슬러 올라오는 波浪의 影響은 거의 없었다. 洪水位와 流速은 災害를 透發시키는 主要因子로 評價되었다. 波浪에 의한 異常高潮와 漲潮流와 潮汐의 滿潮時間 및 最大洪水量이 時間적으로 一致되는 境遇, 河口둑 周邊地域의 水位 上昇과 流速의 停滯現狀으로 浸水狀態가 發生한다. For the investigation of inundation disasters by wave setup in the Nakdong Estuary of the Large River which waves and currents are coexist, the wave surveying data was analyzed and the numerical model was applied to the Estuary. In this study, the result of surveying data analysis shows that waves have little effect on the surroundings. As the result of numerical computation, waves have seldom direct influence upon the barrage and its gates. Also, according to three dimension distribution of waves, it is found that coming up waves along the Estuary channel and the setup of waves have seldom effect barrage structures.

운동신경원성 질환을 동반한 전측두엽 치매 1례

최성혜,나덕렬,김병준,이정일,서연림,김상은 대한신경과학회 1998 대한신경과학회지 Vol.16 No.4