• Proceedings of the Korean Vacuum Society Conference
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• 2013.08a
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• pp.218.1-218.1
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• 2013

GeSbTe 삼원계 칼코겐화물 합금은 광디스크 및 상변화 메모리에서 활성물질로 사용되는 대표적인 재료이다. GeSbTe 합금은 결정질 상과 비정질 상의 두 종류의 상을 갖는데 그 상에 따라 반사율 및 전기저항이 서로 다르기 때문에 활성물질로서 작용한다. GeSbTe 합금 구성원소의 일부를 포함하는 두 종류의 물질로 접합을 형성하고 열처리 공정을 수행함으로써 GeSbTe 합금을 국부적으로 생성하는 방법이 최근에 보고되었다. 이러한 방법을 상변화 메모리 소자 제조에 이용하면 GeSbTe 합금을 제한된 영역에 나노 스케일로 만드는 것이 가능해져서 GeSbTe 합금의 상변화를 유도하는데 필요한 프로그래밍 전류를 낮추는 효과를 얻을 수 있다. 상변화 메모리 소자 내에서의 GeSbTe 합금의 두께 또는 크기는 상변화 메모리 소자의 동작 특성을 좌우하는 중요한 파라미터이며 이것은 열처리 공정 조건에 따라 결정되므로 열처리 공정 조건에 따라 GeSbTe 합금이 생성되는 양상이 어떻게 변화하는지를 밝힐 필요가 있다. 따라서 본 연구에서는 다양한 열처리 온도 조건에서 Ge-Sb-Te 삼성 분계에서의 구성 원소들의 상호확산 거동을 조사하였다. 순수한 Ge 박막과 조성이 다른 SbTe 박막의 접합을 형성하고 773K까지의 온도 범위에서 열처리를 실시하였다. Auger 수직 분석을 이용하여 Ge, Sb, 및 Te 원소의 깊이 방향의 확산 정도를 조사하였으며 그 결과로서 열처리 온도가 증가함에 따라 상호확산 정도가 심해지고 Te 원소가 상호확산에 있어서 중요한 역할을 한다는 사실을 확인하였다.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.15 no.6
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• pp.217-221
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• 2005

The evaporation amounts of volatile Cd, Pb and Zn were characterized by measuring their total concentrations in the EAF dust-clay bodies with various mixing ratio and heat treatment temperature. TCLP test was conducted for evaluating the chemical stabilities of the heavy metal elements. Evaporation amounts and leaching concentrations of heavy metal components were strongly dependent on the mixing ratio and heat treatment temperature. The evaporation of the heavy metal components in EAF dust was effectively suppressed by increasing the clay content. The leaching concentrations of heavy metal components were decreased with increasing clay content and temperature. 20 wt% EAF dust-80 wt% clay sample shows nearly zero evaporation and leaching concentrations of heavy metal components. XRD analysis showed that peak intensities of major crystalline phases such as franklinite and quartz were decreased with increasing the heat treatment temperature which means that the stabilization mechanism of the heavy metals was related with the vitrification process of the $SiO_2$ in the clay.

• Clinics in Shoulder and Elbow
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• v.1 no.1
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• pp.100-108
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• 1998

Surgical treatment of cubital tunnel syndrome has been reported according to a wide variety of techniques since the end of the last century. Theses range from simple decompression to various forms of nerve transposition and medial epicondylectomy. However, we could find only few reports which compare the results between different types of operations. The treatment results of medial epicondylectomy and anterior subcutaneous transposition, were analysed retrospectively. From March 1984 to January 1996, a total of 110 patients had operations for cubital tunnel syndrome. Seventy four of them were followed-up for more than one year, and only they were included in this study. Anterior subcutaneous transposition was performed in 26 patients; and medial epicondylectomy in 48 patients. There were 52 males and 22 females, with an average age of 34 years (range, 13 to 75). The average follow-up period was 40 months (range, 12 to 132). Grading system by Gabel and Amadio were used for evaluation of the patients; pain, sensory and motor dysfunction were checked preoperatively and at last follow-up. In 26 patients of anterior subcutaneous transposition, 7 (27%) were graded as excellent, 11 (42%) good, 3 (12%) fair and 5 (19%) poor. In 48 patients of medial epicondylectomy, 16 (34%) were excellent, 27 (56%) good, 3 (6%) fair and 2 (4%) poor. Sixty nine percent were excellent or good in anterior subcutaneous transposition group, while ninty percent in medial epicondylectomy group. This difference was significant statistically (p<0.01 )., From our experiences, we suggest medial epicondylectomy for the treatment of cubital tunnel syndrome, rather than anterior subcutaneous transposition.

• The Journal of Korean Orthopaedic Ultrasound Society
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• v.1 no.1
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• pp.27-30
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• 2008

Snapping triceps syndrome is a rare condition in which a distal portion of triceps and ulnar nerve dislocate over the medial epicondyle as the elbow is flexed or extended from flexed position. Because it is frequently misdiagnosed as other elbow pathologies, accurate diagnosis is essential and imaging study is often needed to confirm the abnormal movement of ulnar nerve and triceps. Ultraonography is a convenient and effective method which is able to allow continual visualization of soft tissue movement compared to the other imaging modality including MRI. We reported one patient of snapping triceps syndrome who was diagnosed with the use of dynamic ultrasonography and treated with ulna nerve anterior transposition and repositioning of medial head of triceps. And we also provide the usefulness of musculoskeletal ultrasonography for the diagnosis of snapping triceps syndrome.

• Journal of Conservation Science
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• v.30 no.4
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• pp.417-425
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• 2014

Color characteristics of the Cu-Sn alloys (bronze) in as-cast conditions were determined by reference to the $L^*$, $a^*$, $b^*$ color space. Results show that the values of $a^*$ and $b^*$ decrease with the increase in Sn levels, indicating that the colors of bronze alloys are increasingly away from red and yellow with the increase in the fraction of the ${\delta}$ phase while the opposite is true with the ${\alpha}$ phase. It has also been found in similar experiments with the Cu-22% Sn alloys that heat treatments in varying conditions produce subtle differences in their color characteristics as observed in the $L^*$, $a^*$, $b^*$ color space, due likely to the formation of various phases in different fractions.

• Journal of the Korean Magnetics Society
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• v.26 no.3
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• pp.71-75
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• 2016

Monolayer $MoS_2$ is energetically most stable when it has a 1H phase, but 1H to 1T phase transition ($1H{\rightarrow}1T$) is easily realized by various ways. Even though magnetic moment is not observed during $1H{\rightarrow}1T$, $0.049{\mu}_B/MoS_2$ is obtained in local 1T phase; 75% 2H and 25% 1T phases are mixed in ($2{\times}2$) supercell. Most magnetic moment is originated from the 1T phase Mo atom in the supercell, while the magnetic moments of other atoms are negligible. As a result, magnetic/non-magnetic boundary is created in the monolayered $MoS_2$. Our result suggests that $MoS_2$ can be applied for spintronics such as a spin transistor.

• Journal of the Korean Arthroscopy Society
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• v.7 no.1
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• pp.92-95
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• 2003

A 34-year-old man with ACL total rupture due to slip down injury, had received ACL reconstruction using autogenous hamstrings tendon with cross-pin femoral fixation. Postoperative course was as usual. But postoperative 3 months later, he complained posterolateral knee pain, recurrent effusion and mild instability. He was managed repeatitive aspiration and nonsteroid antiinflammatory drugs but was failed to relieve symptoms & signs. In CT scans, perforation of posteromedial femoral cortex of lateral femoral condyle was found. In second look arthroscopy, two pieces of broken femoral cross pin were found in between tibiofemoral Joint which was badly injured cartilage. We considered malposition of pins was the main cause of failure. We propose that femoral tunnel must be made more acute angle and femoral cross-pin guide must be positioned more external rotation 10-20 degree than transepicondylar axis made confirm the cross-pin tunnel position in order to avoid posterior cortex perforation and early failure.

• Journal of the Mineralogical Society of Korea
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• v.5 no.1
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• pp.42-47
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• 1992

The oscillatory zoning pattern in alunite from the Sungsan mine, Korea was studied by the back-scattered electorn(BSE) imaging and electron microprobe analysis. This zoning is not visible under the polarizing microscope, but is spectacularly illustrated in BSE image. Electron microprobe analysis reveals that the zoning is substantially due to the variation in the content of Na substituting for K in the A site of the alunite structure. With increasing brightess in BSE image, conternt of K increases but that of Na decreases. Delicate fine-scale zoning and sharp boundaries between adjacent zones suggest that the zoning would be ascribed to the variation in the composition of hydrothermal fluid around the growing alunite crystals. The effective factors for such a variation would be 1) the fluctuation in the composition of entering fluid. and/or 2) the rapid change in composition of fluid due to the rapid precipitation of more stable. Na-poor alunite.

• Proceedings of the Materials Research Society of Korea Conference
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• 2012.05a
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• pp.106.2-106.2
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• 2012

Ti-Ni합금은 CsCl구조의 B2상, monoclinic 구조의 B19'(M)상과 rhombohedral 구조의 R상(R)이 나타난다고 알려져 있고, 이들 상의 변태에 의해 열탄성 마르텐사이트와 응력유기 마르텐사이트에 의한 형상기억효과와 초탄성 효과를 가지고 있다. 또한 Ti-Ni 합금은 우수한 형상기억특성을 가질 뿐만 아니라 생체적합성, 가공성 및 내식성 등이 뛰어나 공업분야 및 생체분야에서 폭 넓게 활용되고 있다. Ti-Ni합금의 형상기억특성은 냉간가공 후 어닐링 처리의 온도와 시간에 따른 matrix 내 Ni의 농도, 석출물의 밀도와 크기, 전위밀도와 전위주위의 응력장에 의해 영향을 받는다고 알려져 있다. 본 연구에서는 Ti-Ni합금의 형상기억 특성 및 변태온도에 미치는 영향을 조사하기 위해 다양한 냉간가공률의 시료를 제작하여 다양한 온도에서 Annealing 처리를 하여 냉간가공률 및 Annealing 온도가 형상기억특성에 미치는 영향을 조사하였다. Ti-50.4 at.% Ni 합금은 진공 아크 용해로에서 용해 하였으며, 용해된 Ingot는 열간단조 및 열간 압출한 후 냉간 인발과 중간온도에서 어닐링을 반복하면서 직경 0.5mm의 선재로 만들었다. 최종적으로 제작한 선재의 냉간가공률은 9.5%, 18.2%, 34.5%, 45% 이었다. 각 시편은 5X10-5torr의 진공으로 석영관에 진공 봉입하여 각각 673K, 723K, 783K에서 1hr 열처리 하였다. 합금의 형상기억특성과 변태온도는 DSC에 의해 조사되었다. DSC 측정 결과, 냉간가공률이 증가함에 따라 마르텐사이트 변태 온도는 감소하였고, 어닐링 온도가 증가함에 따라 마르텐사이트 변태 온도는 증가하였다. 또한 가공률이 증가하여도 R상 변태온도는 큰 변화가 없었고, Annealing온도가 증가함에 따라 R상 변태온도는 감소하였다. 또한, 형상기억특성은 인장시험기를 이용한 정하중 열싸이클 테스트를 이용하여 평가 하였다. 냉간 가공률이 증가함에 따라 안정한 형상기억특성을 나타내었다.

• Applied Microscopy
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• v.35 no.2
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• pp.81-87
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• 2005

To evaluate the effects of ingestion of alcoholic drinks on the toxicities of industrial compounds, cyclohexane (CH) was intraperitoneally administrated to rats (1.56 g/kg body weght), which had been ingested 15% ethanol for up to 6 weeks, 4 times by once a day and every other day. Following the last treatment of ethanol or CH, blood and lung tissues were collected during 24 hours prior to sacrifice of animals. Comparing with the control group, the lung weight per body weight (%) and the protein content in bronchoalveolar lavage fluid were increased in the ethanol-pretreated group, and the glucose-6-phosphatase activity in lung tissues was decreased in the CH-treated group. In a morphological observations, pulmonary embolus were found in the CH-treated group, whereas a partial pulmonary atelectasis and a much increase in pulmonary embolus were shown in the CH-treated group after pretreated with ethanol for 6 weeks. In conclusion, these results indicate that ethanol pretreatment could enhance CH metabolism and that CH treatment with ethanol pretreatment could induce lung injury due to the increased CH metabolism.