• 전기화학회지
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• 제6권4호
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• pp.266-270
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• 2003

우수한 전기화학적 특성을 갖는 $LiN_{0.8}Co_{0.2}O_2$ 정극 활물질을 평균 $1{\mu}m$ 이하의 균일한 입자 분포를 얻을 수 있는 액상 반응법의 하나인 졸겔법을 이용하여 제조하였다. 제조된 $LiN_{0.8}Co_{0.2}O_2$를 X선 회절과 TEM(transmission electron microscopy)분석을 통하여 미세구조를 분석하였다. 충방전 실험전과 실험후의 미세구조의 변화에 중점을 주어 실험하였으며, 그 결과 졸겔법으로 제조된$LiN_{0.8}Co_{0.2}O_2$ 정극 활물질은 높은 가역 용량을 가지며 뛰어난 싸이클 특성을 가지고 있다 이는 졸겔법으로 제소함으로 인하여 Ni과 Co양이온의 균일한 화학조성을 가지고 있기 때문이라 생각된다. 특히 $LiCoO_2$에서 관찰되었던 cubic spinel disordering과 심각한 구조적 결함이 관찰되지 않았다. 또한 Al 치환으로 인하여 싸이클 특성을 좋아졌지만 용량은 감소하였다.

• 자원리싸이클링
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• 제29권6호
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• pp.27-34
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• 2020

증류수 및 염산용액을 사용하여 용해 및 재결정화 공정을 통한 탄산리튬 내 황산이온(SO42-) 제거에 관한 연구를 진행하였다. 증류수를 사용하여 탄산리튬 용해 시 용액 온도가 감소할수록 탄산리튬의 용해량이 증가하여 2.5 ℃에서 약 1.50 wt.%의 용해량을 나타내었다. 또한 해당 탄산리튬 용해액을 사용하여 탄산나트륨을 첨가하며 재결정화할 경우, 온도 증가에 따라 재결정화율이 증가하여 95 ℃에서 49.00 %의 재결정화율을 나타내었다. 한편, 염산 용액을 사용한 탄산리튬 용해 시 반응 온도의 영향은 없었으며 염산농도가 증가함에 따라 탄산리튬의 용해량이 증가하여 2.0 M 염산 용액에서 7.10 wt.%를 나타내었다. 또한 이 용액을 사용하여 탄산나트륨을 첨가하며 재결정화를 진행하였을 때 반응 온도 70 ℃에서 탄산리튬의 재결정화율은 86.10 %이었고, 황산이온 제거율은 96.50 % 이상이었다. 이후 수세 과정을 통하여 재결정화된 탄산리튬으로부터 나트륨을 99.10 % 이상, 황산이온을 99.90 % 이상 제거하여 순도 99.10 %의 정제된 탄산리튬을 회수할 수 있었다.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제21권3호
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• pp.288-297
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• 1999

This study has been carried out in order to measure the thickness of soft-tissue on lateral cephalographs based on body mass index(BMI) and the change in soft-tissue thickness after surgical correction of mandibular protrusion. The control material in cephalometric study comprised students at The Dental College, 38 persons, aged 21~24 years and the patient material comprised 20 women and 12men, aged 19~28 years with mandibular protrusion.The thickness of the soft-tissue based on BMI in control and study groups, the comparison between them, immediate postoperative change in the thickness, 6 months after surgery, ratio of soft-tissue response and correlation was established through various statistical methods. The result were as follows : 1. The groups based on BMI showed significant differences each other as regards the linear measurements. The thickest soft-tissue was measured 13.6mm, 15.47mm, 16.76mm at Ss, the thinnest at G' 6.0mm, 6.7mm, 7.26mm respectively. 2. The differences between control and experimental groups based on BMI showed to be significant. There were no differences at G'. The soft-tissue in prognathic patients was thicker at Ss, Ls and thinner at Li, Ls, Pg', Gn', Me'. Differential gap was greater in overweight groups. 3. The immediate soft-tissue change after surgery showed the increase at Li, Ls, Pg', Gn', Me' except G', Ls in all groups. 4. The postoperative soft-tissue change 6 months after surgery was similar with immediate change. The soft-tissue shows the increase in the thickness at Li, Pg', Gn', Me' and the greatest difference occurred at Li, 1.1mm, 0.98mm, 1.2mm respectively. 5. The patients with lower BMI index showed higher soft-tissue response to bony movement at Pg'. The immediate response ratio was 91%, 87%, 81% in A,B,C groups respectively, the response 6 months after surgery showed 96%, 91%, 84%.

• Asian Pacific Journal of Cancer Prevention
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• 제13권7호
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• pp.3239-3245
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• 2012

Gliomas are a group of heterogeneous primary central nervous system tumors. Hyperthermia has proven to be a potential therapeutic tool for cancers in the clinic. However, the molecular mechanisms of hyperthermia remain unclear. The objective of this study was to investigate the effects of hyperthermia on the invasiveness in C6 glioma cells and related molecular pathways. Here our data show hyperthermia stimulated the release of tumor necrosis factor-alpha (TNF-${\alpha}$) and decreased C6 glioma cell migration and invasive capability at 30, 60, 120 and 180 min; with increased spontaneous apoptosis in C6 glioma cells at 120 min. We also found mitogen-activated protein kinase (P38 MAPK) protein expression to be increased and nuclear factor-kappa B (NF-${\kappa}B$) protein expression decreased. Based on the results, we conclude that hyperthermia alone reduced invasion of C6 glioma cells through stimulating TNF-${\alpha}$ signaling to activate apoptosis, enhancing P38 MAPK expression and inhibiting the NF-${\kappa}B$ pathway, a first report in C6 rat glioma cells.

• 열처리공학회지
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• 제5권2호
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• pp.103-110
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• 1992

This study is aimed to investigate the effect of various thermomechanical treatments($T_6$, $T_8$ and ITMT) on the microstructure and mechanical properties of an Al-Cu-Li-Ag-Mg-Zr alloy (Weldalite 049) which has been known to strong natural aging response, good weldablity and high strength in $T_6$ sand $T_8$ temper. This experiment was performed by means of differential scaning calorimetry, tensile test, optical and transmission electron microscopy. The tensile strength in the peak aged condition shows 620, 650 MPa in $T_6$ and $T_8$(40% cold work), respectively. Also, The tensile strength is increased with cold working in $T_8$ but decreased at 60% cold working. However, the tensile strength of the intermediate thermomechanical treated speciman(ITMT) is lower than that of $T_6$ temper about 20% but the elongation is higher than two times. It might be predicted that the ITMT is effective processing to improve the toughness of this alloy. In $T_6$, $T_8$ and ITMT, the major strengthening phase is $T_1(Al_2CuLi)$ phases. and the fine $T_1$ phase which are homogeneously precipited in matrix was observed much more in $T_8$ than $T_6$ and ITMT.

• 한국세라믹학회지
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• 제31권2호
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• pp.201-205
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• 1994

Glasses being prepared, measurements and investigations of glass transition temperature and IR edge optical absorption have been performed for the compositions of 56ZrF4-14BaF2-6LaF3-4AlF3-(20-x)NaF-xLiF. Values for transition temperature of these glasses decrease in proportion to increasing LiF mol%(x) in the range of 0

• 한국수산과학회지
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• 제29권6호
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• pp.805-827
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• 1996

Fifteen mysid species representing 4 genera are reported from the west coast of Korea, Of these, Archaeomysis vulgaris (Nakazawa), Archaeomysis japonica Hanamura, Jo and Murano and Acanthomysis tenuicauda Murano are new to the Korean fauna, Acanthomysis aspera li, Acanthomysis fujinagai li, Acanthomysis japonica Nakazawa and Acanthomysis okayamaensis li are new to the western Korean fauna. Detailed description with illustrative figures, ecological notes and keys to species are given.

• 한국세라믹학회지
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• 제25권6호
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• pp.699-703
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• 1988

Domain structures of LiNbO3 crystals grown by Czochralski method were examined according to the growth axis and the rotational speed of crystals. Ring shape and split domain structures were revealed in Z-axis and Y-axis grown crystals respectively. It was found that the domain structures of grown crystals were closely related to the solid-liquid interface shape during growth.

• 한국결정학회지
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• 제9권2호
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• pp.138-142
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• 1998

Lithium triborate, LiB3O5(Mr=119.37), 단결정을 상단 종자정 융액법으로 성장시켰으며, 결정구조를 X-선 회절법으로 연구하였다. 결정계는 사방정계이며 공간군은 Pna21(No. 33)이다. 단위포의 상수는 a=8.432(1) , b=7.364(1) , c=5.110(1) , α=β=γ=90.00o, V=317.3(6) 3, V=4, Dx=2.50 gcm-3, MoKα1, λ=0.71069 , μ=2.3/cm, F(000)=232, T=293 K 이었다. 최종 구조의 오차인자는 520개 회절 점에서 각각 R=0.0222과 wR=0.0582이었다.

• 동의생리병리학회지
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• 제25권6호
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• pp.1119-1128
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• 2011

The aim of this study is to collect and analyze clinical studies on acupuncture therapies of Post-stroke depression, and to suggest a method on study about acupuncture therapies. In this thesis, electronic searches were performed. Also, 6 major journals associated with oriental medicine in Korea were searched manually. Through searching, 27 studies were selected and analyzed. There were 24 controlled studies and 3 non-controlled studies. Treatment methods were acupuncture, electronic-acupuncture, eye-acupuncture, abdominal-acupuncture and pharmaco-puncture. The percentages of these treatment method were 59.2%, 29.6%, 3.7%, 3.7% and 3.7%, respectively. Acupuncture points such as GV20, PC6, ST36, SP6, LV3, GV24, GV26, LI14, LI11, H7, ST40, GB20, GB34 and LI15 were used. In comparison of results before and after acupuncture treatment, there were statistically significant improvement in 26 studies. Based on the results from above, the studies on acupuncture for Post-stroke depression needs to be standardized and more appropriate high-quality study models should be introduced.