• Restorative Dentistry and Endodontics
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• 제25권1호
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• pp.71-77
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• 2000

The color of an esthetic restorative material is controlled primarily by thickness of the material and background color. Although the effects of the two factors on the color coordinates of esthetic dental materials have been reported, the mechanism has not been clarified well enough to explain the effects quantitatively. The purpose of this study was to evaluate the effect of thickness and background color on the color of tooth colored restorative materials quantitatively. One hundred sixty samples were fabricated from two commercial light-cured composite resins and two commercial compomers. The color characteristics and changes in the color coordinates were measured by a tristimulus colorimeter (Model TC-6FX, Tokyo Denshoku Co. Japan) using the CIELAB system. The results were as follows: 1. As thickness increased from 1.0 to 4.0mm, values of $L^*$ $a^*$ $b^*$ changed irregulary for white and dentin color background, but showed no obvious difference in color for black background. 2. The colors of composite resins and compomers were significantly influenced by background color. 3. The color difference was recognized even the same shade name in four representative kinds of composite resins and compomers. 4. As thickness changed, values of color difference for same products and same background color showed constancy, but showed difference for different background color.

• 한국의류산업학회지
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• 제24권6호
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• pp.801-811
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• 2022

In this study, we constructed a database of dyeing concentrations of all reactive dyes used for dyeing linen according to the thickness of the linen fabric and attempted to improve the reproducibility of the dyeing process for the commercialization of linen fabric materials. Linen fabric is a natural cellulose material that is comfortable and suitable for eco-friendly trends. It is a typical summer material with excellent breathability and thermal conductivity, quick moisture absorption and dissipation, and a cool touch. Dyeability and fastness were evaluated depending on the thickness of the linen fabric using a monochlorotriazine (MCT) reactive dye and bifunctional yellow, red, and blue dyes. All three colors of the MCT reactive dye and bifunctional dyes exhibited a darker shade as the fiber thickness of the marker increased. Fastness to washing was excellent at grades 4-5 or higher, regardless of the color of the dye and the number of linen fabrics. Although some color-fastness differences were noted, with the color change occurring most frequently with blue color, the fastness variations with dye type were mostly similar. The results of this study are expected to facilitate the selection of reactive dyes according to the thickness of the linen fabric based on the basic data from the laboratory, which will aid in the mass production of linen fabric and benefit the fashion industry.

• 한국재료학회지
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• 제25권4호
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• pp.196-201
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• 2015

This paper presents the impact of partial shading on $CuIn_xGa_{(1-x)}Se_2(CIGS)$ photovoltaic(PV) modules with bypass diodes. When the CIGS PV modules were partially shaded, the modules were under conditions of partial reverse bias. We investigated the characterization of the bypass diode and solar cell properties of the CIGS PV modules when these was partially shaded, comparing the results with those for a crystalline silicon module. In crystalline silicon modules, the bypass diode was operated at a partial shade modules of 1.67 % shading. This protected the crystalline silicon module from hot spot damage. In CIGS thin film modules, on the other hand, the bypass diode was not operated before 20 % shading. This caused damage because of hotspots, which occurred as wormlike defects in the CIGS thin film module. Moreover, the bypass diode adapted to the CIGS thin film module was operated fully at 60% shading, while the CIGS thin film module was not operated under these conditions. It is known that the bypass diode adapted to the CIGS thin film module operated more slowly than that of the crystalline silicon module; this bypass diode also failed to protect the module from damage. This was because of the reverse saturation current of the CIGS thin film, $1.99{\times}10^{-5}A/cm^2$, which was higher than that of crystalline silicon, $8.11{\times}10^{-7}A/cm^2$.

• 아시안잔디학회지
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• 제18권1호
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• pp.15-27
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• 2004

내음성 지피식물의 생리, 생태학적 특성을 구명하기 위하여 3월 부터 10월 까지 참비비추를 재료로 하여 차광을 달리한 상태에서 이들 인공군락의 물질생산과 생장특징을 분석하였다. 3반복 완전임의배열법에 의하여 각 시험구 공히 식물별 전일광(비교구) 30%, 50%, 70% 차광율의 시험구를 설치하였으며 10일 간격으로 주변효과(Edg effect)를 고려한 Sampling을 실시하였다. 이상의 방법에 의한 연구결과를 다음과 같이 요약 하였다. 1. 8월 초순이후부터 9월 말경까지의 생육과정 차광조절구가 비교구에 비하여 엽수의 높은 증가율을 보였으며, 전시험기간 중 30%차광구에서 9월 10일경 생엽수가 평균 10.1로서 최고치를 보였다. 2. Cont.구는 조절구에 비하여 시험기간 중엽의 신장과 신장율도 공히 낮은 경향을 보였다. 30% 차광구에서 9월 20일경에 엽장이 25.87cm로서 최고치를 보였다. 3. 시험기간중 생육경과에 따른 엽폭의 증가는 각 조절구 공히 8월 중순경까지는 완만한 경향을 보였으나, 8월 22일경부터 9월 10일경의 생육과정에서 엽폭의 증가율이 현저히 높게 나타났다. 4. 엽병길이의 증가는 8월 초순경에서 8월 말경 사이의 생육과정에서 현저히 높은 신장율을 나타냈다. 6. 참비비추의 생육경과에 따른 엽수, 엽장 및 엽폭, 엽병길이의 생장은 30%, 50% 구에서 시험기간중 생육과정에서 비교구와 70%의 조절구에 비하여 현저하게 높은 경향을 보였고, 비교적 적은 광조건에서도 안정된 생육이 이루어 질 수 있는 음지식물로서의 특성을 나타내었다.

• 한국식품영양과학회지
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• 제43권12호
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• pp.1948-1953
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• 2014

본 연구는 배암차즈기를 건조, 데침 및 발효에 따라 항염증 효능성분인 rosmarinic acid, homoplantaginin, luteolin의 함량 변화와 항산화 활성을 조사하였다. Rosmarinic acid는 열풍건조 시 16.42 mg/g, 데친 후 열풍건조 시 10.19 mg/g 순으로 검출되었으며, 동결건조 한 잎과 뿌리는 유의적인 차이가 없었다. 음건 및 동결건조 시에는 각각 8.69와 8.15 mg/g으로 유의성이 인정되었으며, 발효 후에는 0.05 mg/g으로 감소하거나 검출되지 않았다. 동결건조, 음건 및 열풍건조 한 배암차즈기는 $500{\mu}g/mL$의 농도에서 98.5% 이상의 ABTS radical 소거능을 나타내었으며, 데친 후 열풍건조 시에도 87.3%의 우수한 radical 소거능을 나타내었다. 뿌리는 잎에 비하여 ABTS radical 소거능이 낮았다. SOD 유사활성은 $1,000{\mu}g/mL$ 농도에서 6.1~27.8%로 측정되어 ABTS radical 소거능과 차이가 있었다. 배암차즈기에 함유되어 있는 주요 물질이며 항염증 효능 물질로 알려진 rosmarinic acid와 homoplantaginin은 차발효에 의해 거의 소실되기 때문에 배암차즈기를 기능성 차 또는 가공식품 원료로 개발하기 위해서는 차발효(산화발효)보다 동결, 냉풍 및 열풍건조가 적당할 것으로 판단된다.

• 대한치과보철학회지
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• 제41권2호
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• pp.136-147
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• 2003

Statement of problem : Ceramic and composite resin have been used to fulfill the demand for esthetic prosthesis. However, ceramic is easy to break and wears off the opposite natural teeth. Conventional composite resin also has low abrasive resistance and color stability. Ceramic Optimized Polymer (ceromer) was developed in mid-1990s to overcome the shortfalls of ceramic and composite resin. Ceromer has similar abrasiveness with the natural tooth and has relatively high strength. Color stability affects esthetics and long-term prognosis of the prosthesis. Purpose The purpose of this study was to compare color stability of ceromers(2 types : $Artglass^{(R)}$. $Targis^{(R)}$) with ceramics ($Vintage^{(R)}$-polishing, $Vintage^{(R)}$-glazing). Material and Method : The color difference(${\Delta}E^*$) was measured by spectrophotometer with different immersion time. Twenty disks, 3mm in thickness and 10mm in diameter, were fabricated for each specimen in shade A2(Vita Lumin shade guide), Specimens (5 samples in each group) were immersed in the food colorants (Red no.3. Yellow no.4, Blue no.1, Distilled water) for 24 hours, 48 hours and 72 hours respectively. $L^*,\;a^*$ and $b^*$ value were measured with spectrophotometer (CM 503i : Minolta Co., Japan) and mean ${\Delta}E^*$ value was calculated for statistical analysis Results : The results of this study were obtained as follows. 1. The ${\Delta}E^*$ values of all test samples increased with the time of immersion. 2. The ${\Delta}E^*$ values of all materials increased in order of Distilled Water, Yellow no.4, Blue no.1 and fed no.3. There was significant difference between Red no.3 and the other food colorants(p<0.05). 3. The ${\Delta}E^*$ values increased in order of $Vintage^{(R)}$-glazing, $Vintage^{(R)}$-polishing. $Artglass^{(R)}$ and $Targis^{(R)}$. There was significant difference between $Vintage^{(R)}$-glazing and the other materials (p<0.05). Conclusion : By means of the above results, immersion time was found to be a critical factor for color stability of ceromer. For the long-term color stability of prosthesis it is recommended patients having ceromer prosthesis ($Artglass^{(R)},\;Targis^{(R)}$) to reduce the habitual intake of Red no.3 colorants con taming foods.

• Restorative Dentistry and Endodontics
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• 제22권1호
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• pp.358-373
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• 1997

Resin modified glass ionomers were introduced in 1988 to overcome the problems of moisture sensitivity and low early mechanical strength of conventional glass ionomers and to maintain their clinical advantages. The purpose of this study was to evaluate the color stability of four resin modified glass ionomers(Fuji II LC, Vitremer, Dyract and VariGlass), one resin composite material(Z-100), and one conventional glass ionomer(GC Fuji II) under several conditions. These conditions were as follows: 1) before curing, 2) after curing, 3) after polishing, 4) after 500 thermocycling, 5) after 1,000 thermocycling, 6) after 1,500 thermocycling and 7) after 2,000 thermocycling. Three specimens of each material/shade combination were made. Materials were condensed into metal mold with a diameter of 10 mm and a thickness of 2.0 mm, and were pressed between glass plates. The material was polymerized using a light polymerizing unit(Visilux II, 3M, USA). After removal of excess, the surface was polished sequentially on wet sandpapers. A reflection spectrophotometer(Model TC-6FX, Tokyo Denshoku Co., Japan) was used to determine CIELAB coordinates($L^*,a^*$ and $b^*$) of each specimen. CIE standard illumination C was used as the light source. The results were as follows : 1. In comparing different shades of same material, CIELAB color difference(${\Delta}E^*$) value was not significantly different from each other(p>0.05). 2. CIELAB color difference(${\Delta}E^*$) values between after-curing and after-polishing were ranged from 5.53 to 27.08. These values were higher than those of other condition combinations. 3. CIELAB color difference(${\Delta}E^*$) values between before-thermocycling and after-thermocycling were ranged from 1.40 to 7.81. Despite the number of thermocycling increased, CIELAB color difference(${\Delta}E^*$) value was low. 4. The color stability of resin modified glass ionomers was more stable than that of conventional glass ionomers but less stable than that of Z100.

• 한국의상디자인학회지
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• 제9권3호
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• pp.47-57
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• 2007

This study focused on the properties natural dyeing and natural material and on the development of functional material for well-being in apparel industry. Comus officinalis Siebold et Zuccarini is used as natural dyeing material which had been reported that have curable effect for unbalanced immunity, geriatric diseases like urinary tract system, diabetes, hypertension, arthritis, tinnitus, hyperhidrosis and women's diseases like hypermenorrhea. And this material also has anti-cancer effect so that can restraint cancer cells. 3 kinds tester of cotton, wool and silk are dyed by boiled with each dye (flower, fruits, bark of tree) as first dyeing and dried in the shade. These testers are done by post-mordanting method. Aluminium Potassium(Alk(SO4)2), Cuprie Sulfate($CuSO4{\cdot}5H2O$), Stannous Chloride($SnCl2{\cdot}2H2O$), Ferrous Sulfate($FeCl2{\cdot}4H2O$), Titanium Sulfate 24% aqueous solution(Ti(SO4)2) are used as mordants. Dyeing results of Comus officinalis Siebold et Zuccarini flower and bark are shown as yellow color series. And dyeing result of fruits is pink color series. Silk shows the best dyeing property. As the point of view for dyeing property, Ti, Sn, Fe would be the properchoice for mordant. Following results are extracted in this study. Yellow color is resulted in dyeing with Cornus officinalis flower as non-mordanting condition. Yellowish red color is come from dyeing with Comus officinalis fruit as non-mordanting condition. Grayish yellow tone is resulted in dyeing with bark as non-mordanting condition. Orange tone color with Ti-mordanting, green tone color with Sn-mordanting and gray tone color with Fe-mordanting is resulted respectively. However light-fastness of Comus officinalis(flower, fruit, bark) is very low as 1 or 2 level in non-mordanting condition, Comus officinalis flower dyeing is turned out 3 or 4 level and fruit dyeing is 4 or 5 level, bark dyeing is 2 or 3 level with Ti-mordanting respectively. Eventually Comus officinalis fruit has the best light-colorfastness property among all of dyes. dry cleaning colorfastness of Cornus officinalis(flower, fruit, bark) is good as 4 or 5 level in Ti-mordanting condition, perspiration-colorfastness of Cornus officinalis(flower, fruit, bark) is good as 4 or 5 level in Ti-mordanting condition, With these results, this study could conclude that dye-ability, colorfastness problem is getting better after mordanting process and practical usage would be possible.

• Restorative Dentistry and Endodontics
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• 제36권4호
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• pp.324-335
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• 2011

연구목적: 복합레진의 색조를 색 성분요소인 CIE $Lab^*$ 각 성분요소로 측정하고, 동일 시편에 대해서 중합률과 2축 굴곡강도(biaxial flexural strength)를 측정하여 이들의 상관관계를 비교함으로써 복합레진의 중합전, 후의 색 성분요소가 중합률과 물성에 미치는 영향을 알아보고자 하였다. 연구 재료 및 방법: 두 종류의 복합레진 Premisa (Kerr Co.)와 Denfil (Vericom Co)의 법랑질 색조(A1, A2, A3, A4)와 상아질 색조(A2O, A3O)에 대해 원판형의 시편을 제작하여 색성분, 중합률 및 2축 굴곡강도를 측정하였다. 분광광도계를 이용하여 중합 전, 후 및 7일에 CIE $L^*,\;a^*,\;b^*$ 값을 측정하고, 같은 시편에 대해 근적외선분광기를 이용하여 중합 후 2시간과 7일에 중합률을 측정하였다. 중합 7일 후에 색 성분과 중합률을 측정한 후 만능시험기에서 2축 굴곡강도를 측정하였다. 색요소인 CIE $L^*,\;a^*,\;b^*$ 각각의 값과 중합률, 및 2축 굴곡강도의 상관관계를 분석하였다. 결과: 두 종의 광중합형 복합레진은 중합 전과 후에 색 성분요소, 즉 색조의 변화가 있었고, 광중합 후에도 시간이 경과하면서 중합률이 증가되었다. 중합률은 제품, 기간, 및 색조의 영향을 받고(3-way ANOVA, p < 0.05), 굴곡강도는 제품 및 색조의 영향을 받았다(2-way ANOVA, p < 0.05). 중합률은 Premisa 한 제품에서만 중합 전, 후의 CIE $a^*$ component와 유의한 상관관계를 보였고, 굴곡강도도 Premisa에서 CIE $a^*$ 및 CIE $b^*$ component와 음의 상관관계를 보였다(Pearson product moment correlation, p < 0.05). 결론: 광중합 복합레진의 중합률과 굴곡강도는 제품의 중합 전,후의 색 성분에 의해 영향을 받았다.

• 한국작물학회지
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• 제59권4호
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• pp.505-510
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• 2014

고품질 우량인삼 생산을 위한 해가림자재별 인삼의 생육상황과 해가림 아래의 미기상 변화를 조사하였고, 각각의 해가림자재에서 생산된 수삼의 유효성분들을 조사 분석한 결과, 6~8월까지의 해가림자재별로 온도는 차광지>차광판>차광지 순이었고, 투광량도 차광지가 8월에 $381.7{\mu}mol/s/m^2$로 인삼포내 온도가 가장 높은 원인이었다. 2~3년 인삼의 지상부 생육은 차광망>차광판>차광지 순이었으며, 4년근은 차광판=차광지>차광망 순으로 좋았다. 4년근 인삼의 진세노사이드 총함량은 차광판>차광지>차광망 순으로 많았으며, 수삼의 색도는 차광망>차광판>차광지 순으로 높았다.