• Textile Coloration and Finishing
• /
• v.13 no.5
• /
• pp.10-10
• /
• 2001

The Purpose of this study was to investigate spectrophotometric characteristics of Korean knotweed extracts. The properties were evaluated by it′s extracting solvent, effect of metallic ion, variations of pH values and effect of light exposure. The results were as following; The highest absorbance was found in methanol extract of Korean knotweed, while the lowest absorbance was carbon tetrachloride extract. The UV-vis. spectra of Korean knotweed colors in several solvents showed hypsochromic shift of n-π/sup ＊/ transition with the polarity of solvent. Absorbance and peak of UV-vis. spectra of Korean knotweed colors became lower and broader by addition of metallic ion. The light stability in irradiation with xenon ]amp of the color solution with Cu were higher than those of Al and Fe. The UV-vis. spectra of Korean knotweed extracts in various pH values showed bathochromic shift under alkaline condition, and their peaks disappeared after 5 hours exposure.

• Textile Coloration and Finishing
• /
• v.13 no.5
• /
• pp.298-305
• /
• 2001

The Purpose of this study was to investigate spectrophotometric characteristics of Korean knotweed extracts. The properties were evaluated by it's extracting solvent, effect of metallic ion, variations of pH values and effect of light exposure. The results were as following; The highest absorbance was found in methanol extract of Korean knotweed, while the lowest absorbance was carbon tetrachloride extract. The UV-vis. spectra of Korean knotweed colors in several solvents showed hypsochromic shift of $n->\pi^*$ transition with the polarity of solvent. Absorbance and peak of UV-vis. spectra of Korean knotweed colors became lower and broader by addition of metallic ion. The light stability in irradiation with xenon ]amp of the color solution with Cu were higher than those of Al and Fe. The UV-vis. spectra of Korean knotweed extracts in various pH values showed bathochromic shift under alkaline condition, and their Peaks disappeared after 5 hours exposure.

• Textile Coloration and Finishing
• /
• v.24 no.3
• /
• pp.165-172
• /
• 2012

The stability of yellow and red dyes prepared from safflower (Carthamus tinctorius L.) in aqueous solution and in solid state was investigated. External factors such as light irradiation and temperature on the stability were examined during storage. Changes in absorbance of dye solutions and the color changes of fabrics dyed after long time storage were measured. Also, color reproducibility during storage was investigated by dyeing test on various fabrics. Red colorant in aqueous solution was very unstable to light, resulting that about 40% of absorbance were lost in 12hrs. The absorbance of yellow dye solutions was not decreased within 84hrs. In aqueous medium, yellow dye was much more stable than carthamin. Both dyes are relatively stable for long storage when they are stored in solid state compared to when in aqueous solution. Color changes are marginal in both dyes.

• Journal of the Korean Applied Science and Technology
• /
• v.17 no.3
• /
• pp.178-182
• /
• 2000

We have investgated UV-Vis absorbance to observe the photoisomerization using the mixture solutions in chloroform and LB monolayers mixed with DLPE and 8A5H containing azobenzene which showed reversible cis-trans photoisomerization irradiated by alternate lights. We have found that the absorbance spectrums of the mixture solutions and LB monolayers were reversibly induced to cis-trans photoisomerization irradiated by alternate lights. In addition, the absorbance of both solution and LB monolayer mixed with 8A5H and DLPE were reversibly by alternate temperatures. As a results, the 1:1(by volume) mixture ratio of 8A5H and DLPE was more flexible and reversible cis-trans photoisomerization than the others.

• Proceedings of the Polymer Society of Korea Conference
• /
• 2006.10a
• /
• pp.230-230
• /
• 2006

Density functional theory (DFT) calculations using the B3LYP hybrid functional and the 6-311++G(d,p) basis set have been performed to predict the wavelength dispersion of optical absorbance and refractive indices for organic compounds and polymers in the range between the vacuum UV (${\sim}157\;nm$) and near-IR (${\sim}850\;nm$). The DFT calculations can reproduce the experimental dispersions of absorbance and refractive indices with high accuracy and low costs. The calculated dispersions demonstrate that the judicious introductions of $-F\;and\;-CF_{3}$ into alicyclic and heterocyclic compounds are effective in reducing the absorption at shorter wavelengths. In addition, the calculated Abbe numbers that represent the refractive index dispersion in the visble region are linearly proportional to the calculated refractive indices at 589 nm.

• Proceedings of the Korean Society of Dyers and Finishers Conference
• /
• 2008.10a
• /
• pp.25-26
• /
• 2008

일반적인 분산염료, Phthalimide계 중간체로 사용한 분삼염료, Diester계 커플러만 이용한 분산염료와 비교한 Diester계 치환기를 이용한 분산 염료들은 R/C조건과 EtOAc와 증류수로 층분리하여 증류수층의 UV-Vis absorbance은 떨어지고 용해성은 증가한다. 그리고 Thiopene ring만 가진 염료와 비교한 염료들은 같은 파장에서의 UV-Vis absorbance은 떨어져 용해도는 증가하고 Thiopene ring과 Azo group의 분해에 의한 화합물 때문에 단파장에서의 UV-Vis absorbance가 크게 증가하여 염색 폐수의 색도를 감소시킬 수 있다.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.28 no.2
• /
• pp.438-443
• /
• 1999

A livetin solution(LS) containing yolk immunoglobulins(IgY) was separated by treating the egg yolk with natural gum, carrageenan. Carrageenan has been used as a food ingredient. Relative absorbance of IgY LS after proteolysis was investigated. IgY LS was fairly stable to pepsin digestion at pH 3.0. However, IgY LS appeared to be susceptible to pepsin digestion at pH 2.0, showing 18% of relative absorbance and complete breakdown H chain after 30 min exposure. Relative absorbance of IgY LS was considerably high after exposure to trypsin and chymotrypsin for 8 hr. IgY LS showed especially good stability to chymotrypsin digestion.

• The Korean Journal of Food And Nutrition
• /
• v.16 no.4
• /
• pp.379-387
• /
• 2003

The freeze dried young antler was extracted by water and proteases. In case of water extraction, the extraction rate was highest when it was reacted in 5% of concentration for 6 hours at 50$^{\circ}C$. The result of HPLC analysis of extract shows that high molecular peak in water extract was transformed into low molecular polk by proteases. The rate of low molecular peak was highest when bacteria protease was used, and its second highest rate was pepsin, but the effect of papain on it was low, The extraction rate of young antler reacted for 5 hours was 33.4%(absorbance 13.25 at 280nm) of bacteria protease, 22.4%(absorbance 10.06) of papain, and 30.2% (absorbance 11.34) of pepsin. The young antler was boiled for 30min and it was reacted by proteases for 5 hours at 50$^{\circ}C$. The extraction rate of it was 47,6%(absorbance 12,54) of bacteria protease, and 26,4%(absorbance 7,48) of papain, and 45.6%(absorbance 7.23) of pepsin, In protein content, water extract was 52,1%, bacteria protease extract was 37.8%, and in amino acid content, water extract was 16.3%, bacteria protease extract was 31.96%, in ash content, water extract was 8.8%, bacteria protease extract was 5.6% by dry base. In mineral content, water extract contains 3.6% of Ca, 8.6% of P, 0.01% of Mg, 1.4 % of Na, 0.02 % of F, and bacteria protease extract contains 2.5% of Ca, 11.8% of P, 0.046 % of Mg, 2.1 % of Na, 0.018 % of F by dry base.

• Korean Journal of Food Science and Technology
• /
• v.24 no.5
• /
• pp.408-413
• /
• 1992

This study was conducted to determine the effect of the homogenizing grade of sample on absorbance of near infrared reflectance spectrophotometer with which chemical compositions of food were rapidly and effectively analyzed. By the mathematical treatment of absorbance values standard error of prediction was reduced as follows. 1. The absorbance values of various samples ground for the same periods of time were calibrated before or after treatment with first or second derivative in an attempt to accurately predict the components of samples ground for the different periods of time. The standard error of prediction for moisture content were 1.478%, 0.658% and 0.580%, respectively, those for fat content 0.949%, 0.637% and 0.527%, respectively, and those for protein content 0.514%, 0.493% and 0.394%, respectively. Calibration of absorbance values after second derivative treatment showed the highest accuracy in predicting sample components. 2. The absorbance values of various samples ground for the different periods of time were calibrated before or after treatment with first or second derivative in order to accurately predict the components of samples ground for the different periods of time. The standard error of prediction for moisture content were 1.026%, 0.589% and 0.568%, respectively, and those for protein content 0.860%, 0.557% and 0.399%, respectively. The standard error of prediction were lower in the order of calibrations before and after first and second derivative treatments. As a result, calibration of absorbance values after second derivative treatment showed higher accuracy regardless of grinding time of samples.

• Restorative Dentistry and Endodontics
• /
• v.12 no.1
• /
• pp.131-147
• /
• 1986

The purpose of this study was to observe the color matching of lining or filling materials according to the remaining tooth material. Twenty-seven freshly extracted human central incisors were used in this experiments. The teeth were stored in saline solution at room temperature after extraction. All teeth were cut parallel to the tangent to height of contour on labial surface from the lingual surface until the pulp were completely removed. Then 27 teeth were devided into 0.5mm, 1.0mm and 1.5mm reduction groups according to the thickness of cutting the lingual surfaces of teeth. The specimens of control group were three teeth of 27 teeth with cutting the lingual surface same mode as above described. In the specimens of experimental groups, 8 kinds of lining and filling materials; FUJI IONOMER TYPE II (G-C Co. Japan), LINING CEMENT (G-C Co. Japan), Dycal (Caulk, U.S.A.), CLEARFIL F II (Kuraray Co. Japan), Crown Bridge & Inlay Cement (G-C Co. Japan), Copalite (Harry J. Bosworth Co. U.S.A.), HY-BOND (G-C Co. Japan) and LIV-CENERA (G-C Co. Japan); applied on the back of 24 teeth with 0.5mm, 1.0mm and 1.5mm cut thickness of lingual surfaces. Three teeth of control group did not applied linging or filling materials on the back of 3 kinds of different thickness of cutting the lingual surfaces. The absorbances of total 27 specimens were obtained by reflection spectrophotometer. (Cary 17 D, Varian Co, U.S.A.) The following conclusions were drawn from above the results; 1. The absorbance patterns in both experiment and control groups were gradually decreased with increasing wavelength of spectra. 2. The absorbance patterns were not decreased in relation to the kinds of lining or filling materials, but the amount of the remaining tooth materials. 3. In 0.5mm reduction group, FUJI IONOMER TYPE II, LINING CEMENT, LIV-CENERA and Copalite applied on the back of cut lingual surface showed similar absorbance patterns as control group. 4. The specimens which were reduced up to 1.0mm thickness and lined with FUJI IONOMER TYPE II and LINING CEMENT showed the comparable absorbance patterns to the control group. 5. In case of HY-BOND application after 1.5mm reduction were observed the similar absorbance pattern as compared with control group. 6. When Dycal, CLEARFIL and Crown Bridge & Inlay Cement were applied to cut teeth surfaces, there were much differences of absorbance between control groups and experimental groups.