• 열처리공학회지
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• 제7권1호
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• pp.17-24
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• 1994

The evaluation and analysis of diffusivity of lithium for coarsening and coarsening kinetics of ${\delta}^{\prime}$ precipitate in Al-Li-Cu-Mg-Zr alloy aged at $170^{\circ}C$ have been investigated by transmission electron microscopy. With ageing time, ${\delta}^{\prime}$ precipitate coaesened to followed $\bar{\gamma}{\propto}t^{1/3}$ and coarsening kinetics was found to be obeyed to the Lifshitz-Slyozov-Wagner(LSW) theory and diffusivity of lithium for coarsening of ${\delta}^{\prime}$ precipitate in Al-Li-Cu-Mg-Zr alloy was obtained to be $5.85{\times}10^{-17}{\sim}1.53{\times}10^{-16}$ by experimental coarsening rate constant and various coarsening kinetic theory. Diffusivity of lithium measured by using various model but MLSW and Tsumuraya (VI) et al. model in Al-Li-Cu-Mg-Zr alloy is similar to that calculated by the Costas's diffusivity equation. It was, therefore, suggested that additing to the Cu, Mg and Zr element in Al-Li system have no great effect on diiffusivity of lithium for coarsening of ${\delta}^{\prime}$ This suggest that in matrix.

• 한국세라믹학회지
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• 제45권11호
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• pp.725-733
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• 2008

In this study the preparation method of the spherical ADU droplets, intermediate compound of a HTGR nuclear fuel, was detailed-reviewed and then, the characteristics on an ageing and a washing steps among the wet process and the thermal treatment process on the died-ADU${\rightarrow}UO_3$ conversion with the high temperature furnaces were studied. The key parameters for spherical droplets forming are a precise control of feed rate and a suitable viscosity value selection of a broth solution. Also, a harmony of vibrating frequency and amplitude of a vibration dropping system are important factor. In our case, an uranium concentration is $0.5{\sim}0.7mol/l$, viscosity is $50{\sim}80$ centi-Poise, vibration frequency is about 100Hz. In thermal treatment for no crack spherical $UO_3$ particle, the heating rate in the calcination must be operated below $2^{\circ}C$/min, in air atmosphere.

• Archives of Pharmacal Research
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• 제29권2호
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• pp.165-171
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• 2006

Osteoarthritis is thought to be induced by the ageing-related loss of homeostatic balance between degeneration and repair mechanism around cartilage tissue in which inflammatory mediators such as reactive oxygen species, cytokines and prostaglandins are prone to overproduction under undesirable physiological conditions. Phlorotannins are unique polyphenolic compounds bearing dibenzo-1,4-dioxin skeleton which are not found in terrestrial plants but found only in some brown algal species such as Ecklonia and Eisenia families. Phlorotanninrich extracts of Ecklonia cava including LAD103 showed significant antioxidant activities such as DPPH radical scavenging, ferric ion reduction, peroxynitrite scavenging, and inhibition of LDL oxidation, indicating their possible antioxidative interference both in onset and downstream consequences of osteoarthritis. LAD103 also showed significant down regulation of $PGE_2$ generation in LPS-treated RAW 246.7 cells, and significant inhibition of human recombinant interleukin-$1{\alpha}$-induced proteoglycan degradation, indicating its beneficial involvement in pathophysiological consequences of osteoarthritis, the mechanism of which needs further investigation. Since LAD103 showed strong therapeutic potentials in arthritic treatment through several in vitro experiments, it is highly encouraged to perform further mechanistic and efficacy studies.

• 열처리공학회지
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• 제8권1호
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• pp.53-64
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• 1995

A study was made to characterize the microstructures and mechanical properties of the base metal and the heat-affected zone(HAZ) in Cu-bearing HSLA-100 steel. The Gleeble thermal/mechanical simulator was used to simulated the weld HAZ. The relationship between microstructure and toughness of HAZ was studied by impact test, O. M, SEM, TEM, and DSC. The toughness requirement of military specification value was met in all test temperatures for the base metal. The decrease of HAZ toughness comparing to base plate is ascribed to the coarsed-grain and the formation of bainite. Obliquely sectioned Charpy specimens show that secondary crack propagate easily along bainite lath. Improved toughness(240J) at HAZ of $Tp_2=950^{\circ}C$ is due to the fine grain, and reasonable toughness(160~00J) in the intercritical reheated HZA is achieved by the addition of small amount of carbon which affects the formation of "M-A". Cu precipitated during ageing for increasing the strength of base metal is dissolved during single thermal cycle to $1,350^{\circ}C$ and is precipitated little on cooling and heating during subsequent weld thermal cycle. Thus, the decrease of toughness does not occur owing to the precipitation of Cu.

• Advances in Traditional Medicine
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• 제10권4호
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• pp.239-253
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• 2010

Coenzyme $Q_{10}$ ($CoQ_{10}$, or ubiquinone) is an electron carrier of the mitochondrial respiratory chain (electron transport chain) with antioxidant properties. In view of the involvement of $CoQ_{10}$ in oxidative phosphorylation and cellular antioxidant protection a deficiency in this quinone would be expected to contribute to disease pathophysiology by causing a failure in energy metabolism and antioxidant status. Indeed, a deficit in $CoQ_{10}$ status has been determined in a number of neuromuscular and neurodegenerative disorders. Primary disorders of $CoQ_{10}$ biosynthesis are potentially treatable conditions and therefore a high degree of clinical awareness about this condition is essential. A secondary loss of $CoQ_{10}$ status following HMG-CoA reductase inhibitor (statins) treatment has been implicated in the pathophysiology of the myotoxicity associated with this pharmacotherapy. $CoQ_{10}$ and its analogue, idebenone, have been widely used in the treatment of neurodegenerative and neuromuscular disorders. These compounds could potentially play a role in the treatment of mitochondrial disorders, Parkinson's disease, Huntington's disease, amyotrophic lateral sclerosis, Friedreich's ataxia, and other conditions which have been linked to mitochondrial dysfunction. This article reviews the physiological roles of $CoQ_{10}$, as well as the rationale and the role in clinical practice of $CoQ_{10}$ supplementation in different neurological diseases, from primary $CoQ_{10}$ deficiency to neurodegenerative disorders. These will help in future for treatment of patients suffering from neurodegenerative disease.

• Journal of Animal Science and Technology
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• 제46권1호
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• pp.97-106
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• 2004

본 실험은 현장에서 발생할 수 있는 도축 전개체 관리와 도축 후 냉각온도의 편차가 숙성기간동안 육질에 미치는 영향을 관찰하기 위해 설계되었다. 총 20 두 랜드레이스를 도축 하루 전날부터 절식(n = 10)한 처리구와 도축일 아침까지 급여(n = 10)한 처리구 중에 각각 5마리씩을 무작위 선발하여 도축 전 스트레스(n = 10)와 무 스트레스(n = 10) 처리하엿다. 분할 후 좌도체는 $6^{\circ}C$에 우도체는 -$3^{\circ}C$의 도체 냉각실에서 24시간 냉각하였다. 사후 강직기와 도축 후 24시간의 pH, 온도, 유리 칼슘이온, 단백질 분해도를 측정하였으며, 1일째 근절길이, $1^{\circ}C$에서 3일 및 7일째 드립량, 1, 3, 7일째 육색, 전단력 및 가열 감량을 측정하였다. 본 실험 조건에서 도축 직전 15분 동안 몰이스트레스는 유리 칼슘량을 제외한 대사속도 및 육질 특성에 영향을 주지 않았다. 절식하지 않은 구는 절식한 처리구와 비교하여 1시간과 24시간에 빠른 pH 하강을 보였고 (P < 0.1), - $3^{\circ}C$ 냉각 조건에서는 $6^{\circ}C$에서 냉각한 처리구와 비교하여 도축후 3시간부터 완만한 pH 강하속도(P < 00.1)을 보였으나 최종 pH가 5.7 ${\sim}$ 5.8로 처리 구간에 큰 차이가 없었다. pH 6.2에서 절식과 냉각방법간에 상호 작용이 있었는데, 절식하지 않은 도체를 $6^{\circ}C$에서 냉각했을 경우 온도가 $33.3^{\circ}C$로 절식시킨 처리구를 - $3^{\circ}C$에서 냉각한 처리구와 비교하여($22.2^{\circ}C$) 11$^{\circ}C$ 더 낮은 온도를 보였다. 근절길이는 1.7 ${\sim}$ 1.8 ${\mu}m$로 처리간에 큰 차이를 보이지 않았으나, 24시간째 전단력은 절식처리구에서 약 2kg 높았다(P < 0.05) 영향을 받았는데, 절식시킨 시험구에서 낮은 값을 보였다. 냉각실 온도는 전단력과 육색에 영향을 미치지 않았으나, -$3^{\circ}C$ 냉각이 가열 감량을 유의적으로 감소시켰다(P < 0.05), 숙성기간 동안 전단력은 사료 급여를 하지 않은 도체에서 도축 후 1일에 약 6.5 kg으로 도축전까지 급여한 구보다 높았는데( P <0.05), 이 결과는 빠른 pH 하강과 유리 칼슘이온의 방출로 높은 도체 온도에서 단백질 분해 효소의 높은 활성과 관련된 것으로 판단되었고, 이것은 빠른 Desmin 분해 속도가 뒷받침하였다. 하지만 숙성 7일째에는 처리간의 전단력 차이는 관찰되지 않았다. 가열 감량 숙성기간동안 가열 감량을 크게 증가시켜 숙성 7일째에는 유의적으로 높은(P < 0.01) 가열 감량을 유발하였다. 이러한 결과는 육색과도 연관 되었는데, 육색은 결과는 육색과도 연관 되었는데, 육색은 진공포장 후 7일 동안 $1^{\circ}C$에서 숙성한 결과 절식시킨 시험구와 지교하여 도축 전 급여가 더 밝고 붉은색(P < 0.05)을 나타냈다. 명도는 숙성 7일째에 유의적으로 증가하였고, 적색도는 3일째에 증가하였으나 7일째에는 변화가 없었다. 이러한 변화는 통계적으로는 유의성이 관찰되었으나 그 차이점은 미미했다. 본 실험결과는 도축 전날까지 급여 또는 절식 여부는 숙성 3일 이상일 경우 연도에는 영향을 미치지 않으나, 도축일 아침까지 급여가 보수력을 감소시키므로 도축 하루 전날부터 절식하는 것이 육질을 증가시킨다는 것을 시사하고 있다.

• 한국축산식품학회지
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• 제24권1호
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• pp.37-43
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• 2004

인삼성분이 함유된 돼지고기 생산을 위하여 축산연구소에서 사육된 100 kg 내외의 랜드레이스 30두를 이용하여 인삼부산물을 14일간 첨가수준별로 급여하여 생산돈 돈육의 저장중 육질특성을 분석한 결과는 다음과 같았다. 저장기간 동안의 육색 L값의 변화는 대조구보다 인삼껍질 3% 급여구에서 5일과 10일차에 높게 나타났으며(p<0.05), 또한 전반적으로 처리구가 대조구에 비하여 높은 경향을 보였다. 전단력은 대조구와 인삼껍질 급여구간에는 저장 15일까지는 유의적인 차이가 나타나지 않았다. 저장 20일차에는 인삼껍질 6% 급여구가 대조구에 비하여 높게 나타났으며(p<0.05), 가열감량은 인삼껍질 9% 급여구가 대조구보다 낮은 경향을 보였으며, 저장 15일차에서는 인삼껍질 3%와 9% 급여구에서 낮은 경향을 보였다(p＜0.05). 보수력은 처리간에 차이를 보이지 않았으나, 저장 20일차에 잎줄기 추출물 5.5% 급여구가 가장 감소가 적어 보수력이 가장 좋은 것으로 나타났다. 지방산패도(TBA)에서는 저장 5일부터 대조구에 비하여 인삼부산물을 급여한 시험구에서 유의적으로(p<0.05) 낮은 결과를 보였으며, 단백질 변패도(VBN)은 저장 5일차와 20일차에서 인삼껍질 9% 급여구와 인삼 잎줄기추출물 5.5% 급여구에서 유의적으로 낮은 결과를 보였다(p＜0.05). 이상의 결과로 인삼의 사포닌 성분이 돈육내 축적 가능성을 보여주는, 인삼부산물 급여구의 전단력, TBA 및 VBN의 분석결과 숙성지연 및 저장 중 식육의 변패지연 효과가 있는 것으로 나타나 돈육으로서 저장에 따른 상품으로 이용이 가능한 것으로 나타났다.

• 한국작물학회지
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• 제41권3호
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• pp.274-285
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• 1996

Po1ymer를 피복한 벼 종자의 종자세 향상과 환경 적응성을 구명하기 위하여 10종의 Polymer를 피복하여 수분흡수력, 호흡량, 발아력 및 포장 출아율 등을 조사하였던 바 그 결과를 요약하면 다음과 같다. 1. Polymer피복 종자의 수분흡수율은 포화습도에서 klucel이 가장 높았고 PVP가 가장 낮았으며, 물에 침청할 때는 klucel이 가장 높았고 maltrin이 가장 낮았다. 2. Polymer 피복 종자의 호흡량은 화영벼 와 일품벼 에서 polymer 피복 종자가 낮았으나, 대청벼와 진미벼는 오히려 높았는데 그 정도는 sepiret 피복 종자가 PVP 피복 종자보다 높았다. 3. Polymer피복 과정 중 기계에 의한 종자피해 정도는 발아율이 1% 내외로 저하되어 극히 미미 하였다. 4. 종자세가 양호한 종자에서는 polymer 피복에의한 발아율의 향상은 없었으나 대부분이 95% 이상의 발아율을 보였고 waterlock, surelease 45 및 sepiret등이 특정 품종에서 발아율이 극히 저조하였다. 5. 발아세는 sepiret 피복으로 향상되었고, PVP 피복으로는 약간 저하하였다. 6. Polymer피복 후 노후화 처리 종자의 발아율은 대부분의 polymer에서 피복 종자가 무처리 종자에 비하여 약간 높았으나 sepiret과klucel피복한 종자의 발아율은 현저하게 저하하였다. 7. 저온 발아성은 daran 8600, maltrin, sacrust 및 opadry 등에서는 향상되었고 나머지 polymer는 저해하였는데, 특히 PVP의 발아율이 가장 낮았다. 8. 초장은 대부분의 polymer 피복 종자에서 컸으나 watelock, PVP, maltrin등의 Polymer에서는 작았다. 저온 발아시 초장은 polymer피복으로 오히려 단축되었다. 9. 포장 출아율은 피복 종자가 훨씬 높았으며 출아 소요시간도 훨씬 단축되었다. 포장수분함량 90 %에서 출아율이 가장 양호하였고 출아 소시간도 단축되었으며, 95년 종자가 94년 종자보다도 출아률이 높았고 출아시간도 단축되었다. PVP가 sepiret보다 더 양호한 출아율을 나타냈다.

• 한국실내디자인학회논문집
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• 제18권5호
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• pp.183-190
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• 2009

Increase in the elderly population has given rise to various social problems throughout Korean society, and what is more, although the greater demand of medical treatment, its development is still in its early stages. Given that Specialized Geriatrics Hospital has stood amid a range of spatial complication and it should faithfully reflect the needs of elderly population, we need a better understanding of Specialized Geriatrics Hospital. This study suggested the foundation to plan of Specialized Geriatrics Hospital through analyzing and evaluating spatial configuration of Specialized Geriatrics Hospital by "Space Syntax" and "J-Graph" The study focused on Specialized Geriatric Hospitals existing in Korea which owned more than 100 beds. The result of this study is summarized as follows; First, the rate of separated convex showed that the portions of the Treatment of outpatients and Supply have increased, but onthe other hand the portion of the The ward has been on the decrease. Second, in the case of Treatment of outpatients, it was structured Tree-shaped and the Tree-shaped could be separated with two types: waiting room and wailing room with lounge. in the case of The ward, it was structured Tree-shaped and also Ring-shaped. The more recently opened Geriatrics Hospital, the closer to Ring-shaped. Third, the access to the Ccentral treatment was low though the access to the core of the each floor was high. Fourth, in the progress of intelligibility, the fact that its value has decreased is becoming a serious problem of medical development for the elderly population finally, according to J-graph's analysis, the hallway made the spatial depth of rooms and public space more deepened. This caused by scattered arrangement of public spaces. As the only planning were considered in this study, It therefore needs more diversified approaches considering physical factors such like real distance and area.

• 한국재료학회지
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• 제26권7호
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• pp.388-392
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• 2016

A cold roll-bonding process was applied to fabricate an AA1050/AA6061/AA1050 laminate complex sheet. Two AA1050 and one AA6061 sheets of 2 mm thickness, 40 mm width and 300 mm length were stacked up after surface treatment that included degreasing and wire brushing; material was then reduced to a thickness of 3 mm by one-pass cold rolling. The laminate sheet bonded by the rolling was further reduced to 1.2 mm in thickness by conventional rolling. The rolling was performed at ambient temperature without lubricant using a 2-high mill with a roll diameter of 210 mm. The rolling speed was 5.0 m/sec. The AA1050/AA6061/AA1050 laminate complex sheet fabricated by roll bonding was then hardened by natural aging T4) and artificial aging (T6) treatments. The microstructures of the as-roll bonded and the age hardened Al complex sheets were revealed by optical microscope observation; the mechanical properties were investigated by tensile testing and hardness testing. The strength of the as-roll bonded complex sheet was found to increase by 2.9 times compared to that value of the starting material. In addition, the hardness of the complex sheets increased with cold rolling for AA1050 and age-hardening treatment for AA6061, respectively. After heat treatment, both AA1050 and AA6061 showed typical recrystallization structures in which the grains were equiaxed; however, the grain size was smaller in AA6061 than in AA1050.