• 한국세라믹학회지
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• 제50권6호
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• pp.460-465
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• 2013

Plate-shaped inorganic particles are coated onto a stainless steel substrate by the electrophoretic deposition of a precursor slurry which includes the inorganic particles of $Al_2O_3$ and polymer resin in mixed solvents to mimic the abalone shell structure, which is a composite of plate-shaped inorganic particles and organic interlayer binding materials with a layered orientation. The process parameters of the electrophoretic deposition include the voltage, coating time, and conductivity of the substrate. In addition, the suspension parameters are the particle size, concentration, viscosity, conductivity, and stability. We prepared an organic-inorganic composite coating with a high inorganic solid content by arraying the plate-shaped $Al_2O_3$ particles and electrophoretic resin via an electrophoretic deposition method. We analyzed the effect of the slurry composition and the electrophoretic deposition process parameters on the physical, mechanical and thermal properties of the coating layer, i.e., the thickness, density, particle orientation, Young's modulus and thermogravimetric analysis results.

• 한국세라믹학회지
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• 제52권4호
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• pp.284-289
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• 2015

This study examined carbon layer coating on silicon carbide (SiC) fibers by utilizing solid-state and wet chemistry routes to confer toughness to the fiber-reinforced ceramic matrix composites, as an alternative to the conventional pyrolytic carbon (PyC) interphase layer. Electrophoretic deposition (EPD) of carbon black nanoparticles using both AC and DC current sources, and the vacuum infiltration of phenolic resin followed by pyrolysis were tested. Because of the use of a liquid phase, the vacuum infiltration resulted in more uniform and denser carbon coating than the EPD routes with solid carbon black particles. Thereafter, vacuum infiltration with controlled variation in phenolic resin concentration, as well as the iterations of infiltration steps, was improvised to produce a homogeneous carbon coating having a thickness of several hundred nanometers on the SiC fiber. Conclusively, it was demonstrated that the carbon coating on the SiC fiber could be achieved using a simpler method than the conventional chemical vapor deposition technique.

• 한국세라믹학회지
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• 제46권5호
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• pp.447-451
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• 2009

Continuous SiC fiber-reinforced SiC composites ($SiC_f$/SiC) were fabricated by electrophoretic deposition (EPD). Nine types of slurries with different powder contents, binder resin amounts and slurry pH were deposited on Tyranno$^{TM}$-SA fabrics by EPD at 135 V for ten minutes to determine the optimal conditions. Further EPD using the optimum slurry conditions was performed on fabrics with four different pyrolitic carbon (PyC) thicknesses. The density of the hot-pressed composites decreased with increasing PyC thickness due to the difficulty of infiltrating the slurry into the narrow gaps between the fibers. On the other hand, the mechanical strength increased with increasing PyC thickness despite the decrease in density, which was explained by the enhanced crack deflection with increasing PyC thickness. The $SiC_f$/SiC composites showed the highest density and flexural strength of 94% and 342 MPa, respectively, showing EPD as a feasible method for dense $SiC_f$/SiC fabrication.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1996년도 하계학술대회 논문집 C
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• pp.1498-1501
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• 1996

To evaluate insulating properties of polyimide thin film on high temperature over $100\;^{\circ}C$, polyimide film were prepared by electrophoretic deposition onto metal surface from nonaqueous emulsion. The emulsion is made by adding a solution of the resin to a precipitant, which is an organic liquid compeltely miscible with the solvent of the organic resin solution, but which does not dissolve the resin. The polyimide film obtained by annealing shows good insulation properties of 5.8 MV/cm at elevated temperature and breakdown strength of the film reveals thickness dependence.

• 대한핵의학회지
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• 제7권2호
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• pp.1-12
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• 1973

The most commonly used methods for determining thyroxine binding globulin(TBG) concentration as the total thyroxine-binding capacity utilize electrophoretic seperation of serum. Although technically simple, the electrophoretic method is time consuming and is limited in the number of samples which can be run in a single assay. The author presented a single $T_4$ load ion exchange resin method as an approach to simplify the technique as with clinical practicability and results were analyzed. For construction of the standard curves, serum mixtures were diluted with barbital buffer.which effectively blocked $T_4$-binding to TBPA. For each serum dilution, a constant amount of $T_4-^{125}I$ and increments of unlabelled $T_4$ were added. After incubation in water bath, resin beads were dispensed to the samples which binded all $T_4$ not bound to TBG. The radioactivity in the supernatant was counted in the gamma scintillation counter. Each standard curve was plotted from the percent counts in the supernatant and total $T_4$ in each tube. Unknown samples were diluted to 1:40 and ran at a single $T_4$ loading concentration, and the TBG capacity of the samples was able to be read on the standard isobars. The following results were obtained. 1) Mean and standard deviation for TBG capacity in normal population was $28.6{\pm}5.09{\mu}g\;T_4/100ml$. 2) $24.9{\pm}3.87{\mu}g\;T_4/100ml$ in hyperthyroidism showed low TBG capacity comparing to normal population.(p<0.025) 3) $31.0{\pm}2.40{\mu}g\;T_4/100ml$ in hypothyroidism showed high TBG capacity tendency comparing to normal population. 4) Reversed correlationship existed between TBG capacity and $T_3$ resin uptake(r=-0.624), TBG capacity and serum $T_4$ value (r=-0.859), and TBG capacity and free thyroxine index(r=-0.623). The author assumes that this method of assay is considerably simpler in instrumentation and technique than any other assays traditionally being used, and seems to be more practical for routine clinical laboratory use.

• 약학회지
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• 제55권1호
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• pp.1-10
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• 2011

Mastic is a bleed resin formed in pistacia lentiscus tree extract form the anacatdiaceae family. Mastic is used as a food ingredient in the Mediteraanean resin, and has been used by local inhabitants as a traditional medicine for relief of upper abdominal discomfort, dyspepsiaand peptic ulcer. Clinically, mastic has been effective in the treatment of benign gastric and duodenal, ulcers, giving symptomatic relief and endoscopically proven healing. In this study, to enhance activiteies of poorly water soluble Mastic with oils, surfactants and cosurfactants and then the mixure was microemulsified in aqueous media under condition of gentle agitation and digestive motility that would be encountered in the gastrointestinal tract. Formulation development and screening were based on phase diagrams and characteristics of resultant microemulsion. For optimum mastic formulation, microemulsions with various ratio (w/w%) of mastics, oils, surfactants and cosurfactants were prepared and their solubility was evaluated by monitoring particles size in their buffer through visual asessment and electrophoretic light scattering spectrophotomerter (ELS). In vitro activity of self microemulsified mastic (SME mastic) was determined by minimum ingibition concentration (MIC) test against a panel of Helicobacter pylori (H. pylori) clinical strains. Additionally, in vivo activity of SME masitc was investigated us mouse infected by CH275 of H. pylori. The mean diameter of SME mastic was less then 100 nm in water and SME mastic was showed similar antiboisis effect compared to tometronidazole, clarithromycin and omeproazole. Consequently, SME mastic would be effective system to exterminate H. pylori. If mastic were dose with combined treatment, mastic might augur well for effect of H. pylori eradication as good remedy.

• 한국산림과학회지
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• 제29권1호
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• pp.102-114
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• 1976

소나무속(屬) Diploxylon아속(亞屬)의 종간잡종(種間雜種)인 일대잡종(一代雜種) ${\times}$ P. rigitaeda와 여교잡종(戾交雜種)인 ${\times}$ P. rigida rigitaeda와 ${\times}$ P. rigitaeda rigida, ${\times}$ P. rigitaeda의 $F_2$ 및 자연잡종(自然雜種)인 ${\times}$ P. rigitaeda Wind등(等)의 임성종자확득율(稔性種子穫得率)을 기준(基準)으로 한 교배친화력(交配親和力)과 분류학상(分類學上)의 유연관계(類緣關係)를 검토(檢討)하는 동시(同時)에 조림지(造林地)에 있어서의 생장비교(生長比較), 침엽(針葉)의 해부형태비교(解剖形態比較), phenol성(性) 물질(物質)에 의(依)한 특성비교(特性比較) 및 isoperoxidase의 변이비교등(變異比較等)을 구명(究明)하여 금후계획적조림(今後計劃的造林)에 공헌(貢獻)할 잡종채종림조성(雜種採種林造成) 여부(與否)와 우량잡종간(優良雜種間) 및 기량친종간(其兩親種間)의 차이점(差異點)을 분별(分別) 관찰(觀察)한 결과(結果) 다음과 같은 성적(成績)을 얻었다. 1. 각공시수종(各供試樹種)을 Shaw, Pilger 및 Duffield등(等)의 분류식(分類式)에 준(準)하여 각조합별(各組合別) 임성종자확득율(稔性種子穫得率)을 기준(基準)으로 교배친화력(交配親和力)과 유연관계(類緣關係)를 검토(檢討)한바 각조합(各組合)의 양친종간(兩親種間)에는 상당(相當)한 교배친화력(交配親和力)이 있었고, 근연간(近緣間)임을 알 수 있었으며, 각조합별(各組合別) 최고임성종자확득율(最高稔性種子穫得率)은 67~87%이었다. 2. 각조림지(各造林地)에서의 수고(樹高) 및 근시경(根元徑) 생장비교(生長比較)에서 수종간(樹種間)에 1~5% 수준(水準)으로 고도(高度)의 유의성(有意性)이 있었으므로 재적비(材積比)에서도 P. rigida 보다 28~80%의 보다 월등(越等)한 생장(生長)을 보여 조림상(造林上) 유용성(有用性) 가치(價値)가 있는 우수잡종(優秀雜種)으로 기대(期待)되며, ${\times}$ P. rigitaeda를 제외(除外)한 잡종송(雜種松)은 내한성(耐寒性)에 있어서 P. rigida의 형질(形質)을 받어 전연(全然) 동해(凍害)를 받지 않았으므로 내한력(耐寒力)이 강(强)함을 알 수 있었다. 3. 침엽(針葉)의 해부형태(解剖形態)에 있어서 제형질중(諸形質中) 일부(一部) 예외(例外)도 있었으나 각잡종송(各雜種松)은 대부분(大部分)이 hypoderm에서 biform이었고, resin canal에서는 중위(中位)를 나타냈으며, fibrovascular bundle에서는 대부분(大部分)이 양친종(兩親種)의 중간형질(中問形質)을 나타냈으므로 각잡종(各雜種)과 그 양친종간(兩親種間)의 식별(識別)은 어느정도(程度) 가능(可能)함을 보았다. 4. Phenol성물질(性物賢)에 의(依)한 특성비교(特性比較)에서 각공시잡종(各供試雜種)이 P. rigida와 공(共)히 Rf値 0.66인 phenol물질(物質) 7번(番)이 담황색(淡黃色)으로 반응(反應)되었으나 P. taeda에는 반응(反應)이 나타나지 않았으므로 양친종간(兩親種間)에는 현저(願著)한 식별(識別)을 할 수 있었다. 5. 과산화(過酸化) 동위효소형(同位酵素型)의 변이(變異)는 각공시수종(各供試樹種)에 출현(出現)된 band의 수(數)와 위치(位置) 및 활성도(活性度)의 차이(差異)가 상이(相異)하므로 어느정도(程度) 식별(識別)이 가능(可能)함을 알 수 있었다.