• Journal of Conservation Science
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• v.32 no.4
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• pp.459-469
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• 2016

The goal of this study was to examine property changes induced by the choice of filler used with an epoxy resin that was developed in 2014 to restore cultural assets and consider the applicability of the resin as a restorative agent. The properties of putty mixed with 9 types of fillers and as-developed resins were compared with those of existing materials with regard to stability, superiority and applicability. The potential of the putty as an alternative material was also examined. The materials produced the best adhesiveness, color change and hardness results when mixed with lime. Micro balloon produced the best wear rates and hardening times, while diatomite produced the best tensile and compressive strengths. A plaster and white mineral pigment mixture produced the best specific gravity. Every material except for lime exhibited about 2.5-20 times higher wear rates than the existing material, which is thought to exhibit an excellent cutting force. The hardening time was enhanced by about 0.5-9 times to improve convenience. The stability of the relic was also ensured by improving hand staining without any shrinkage or deformation. The material exhibited about 0.5-27 times less yellowing. Thus, it is thought to be a material that can reduce property changes and reduce the degree of relic fatigue which occurs during reprocessing and sense of difference from relic.

• Journal of Conservation Science
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• v.34 no.2
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• pp.69-76
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• 2018

Lead-based pigments (Lead White, Massicot, and Red Lead) are known to cause discoloration easily in indoor air environments. This study was conducted to investigate the effect of representative indoor air environment factors ($O_2$, $CO_2$) on lead-based pigments. As a result of the experiment, almost all of the specimens showed changes of more than ${\Delta}E=5.0$ in their values of chromaticity under $O_2$ (99%, RH 99%) and $CO_2$ (36,000 ppm, RH 99%) environments. Scanning electron microscopy also showed that the pigment particles lose sharpness of the edge. Furthermore, under the degradation, the intensities of the characteristic peaks in the X-ray diffraction patterns were decreased, and Lead White, Massicot, and Red Lead exposed to $CO_2$ (36,000 ppm, RH 99%) were shown to include the new material cerussite ($PbCO_3$). In particular, Plattnerite ($PbO_2$) was identified on Massicot, and for white lead, the characteristic peaks disappeared and those of Cerussite were identified. It was confirmed that chemical change with discoloration can occur when these lead-based pigments are exposed to a high-humidity $CO_2$ environment.

• Applied Biological Chemistry
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• v.41 no.5
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• pp.399-404
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• 1998

Genipin was obtained from hydrolysis of geniposide isolated from gardenia fruits with ${\beta}-glucosidase$. Reaction of genipin with glycine, alanine, histidine, lysine, phenylalanine and glutamate in aqueous buffer solution converted colorless starting materials to blue pigments. Effect of pH for the formation of blue pigments was tested using UV/Vis spectrophotometer. The optimum pH for the formation of blue pigments was 7.0. No pigment and trace amounts were formed at acidic (pH 3.0) and alkaline (pH 12.0) conditions, respectively. The amount and tincture of blue color were distinct with different amino acids. In contrast with lysine $({\lambda}_{max}=573\;nm)$, glycine $({\lambda}_{max}=595\;nm)$, phenylalanine $({\lambda}_{max}=602\;nm)$ and alanine $({\lambda}_{max}=595\;nm)$, the reaction of genipin with histidine $({\lambda}_{max}=601\;nm)$ and glutamate $({\lambda}_{max}=601\;nm)$ produced relatively small amounts of blue pigments. Rate constants for the formation of blue pigments from genipin with amino acids at various temperatures $(60,\;70,\;80,\;90^{\circ}C,\;pH\;7.0\;phosphate\;buffer)$ were obtained. Rate constants of genipin with basic amino acids were larger than neutral or acidic amino acids. Arrhenius activation energies of the formation of blue pigments indicated that activation energy of glycine $(E_A=9.8\;kcal/mol)$ was especially lower than those of other amino acids $(E_A=13.3{\sim}15.4\;kcal/mol)$.

• Applied Biological Chemistry
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• v.19 no.3
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• pp.145-154
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• 1976

Studies have been carried out to design a suitable consumer size package from flexible packaging material to hold 100 grams of Chilli powder and 250 grams of whole chilli which are moisture and color sensitive. 1. Sorption characteristics of the chilli powder has revealed that moisture sorption is rapid above 55 per cent R.H., and the product is fairly hygroscopic. Further, an equilibrium moisture content of about 15 per cent at 70 per cent R.H., appears to be critical from the point of microbial spoilage of chilli powder. 2. Studies on the colour (Capsanthin) changes of chilli powder equilibriated to different moisture content, have revealed that colour changes during storage is greatly influenced by the moisture content and temperature decreases the capsanthin content of chilli during storage. 3. From the studies, it can be inferred that the sunlight exhibits pronounced effect in bleaching of colour and brings about maximum discolouration of the red pigment in chilli. 4. From the packaging and storage studies of chilli powder in different flexible films, it can be concluded that for long-term storage, the aluminium foil laminate is unique in offering maximum protection from various physico-chemical changes. For short-term storage and for fairly good moisture and colour protection, amber or black polyethylene, high-density polyethylene and Saran/Cello/Saran poly laminate pouches appear to be suitable alternatives.

• Journal of Korean Society of Environmental Engineers
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• v.35 no.8
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• pp.607-612
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• 2013

Soil ecological risk assessment requires terrestrial toxicity data based on trophic levels including plants, earthworms, nematodes, and springtails. To expand the trophic levels, it is needed to consider primary producer algae, nearly distributed in terrestrial environment, as representative terrestrial test species. In this study, we collected research cases focused on soil-related test species and exposure media from SCI papers, and analyzed exposure media, test species, test chemicals, and other test methods, for reviewing research trends of soil-related algal toxicity. Up to now, in the soil-related algal toxicity, test species were 8 cases (Pseudokirchneriella subcapitata, Chlorella vulgaris, Scenedesmus bijugatus, Chlorococcum infusionum, Scenedesmus subspicatus, Nostoc linckia, Synechococcus elongatus, and Chlorococcum sp.) and endpoints were cell count or photosynthetic pigment content. Also, 5 of exposure media were liquid medium, soil extracts, porewater, agar medium, and soil. Most of papers used algae isolated from natural soils or soil extracts. There were only one case for assessing algal toxicity in soil medium. More researches regarding algal toxicity in soil environments need to be conducted consistently.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.29 no.3
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• pp.393-408
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• 1996

The effect of various levels of ascidian tunic extracts and carophyll pink on the growth rate, pigmentation, lipid and total cholesterol accumulation, and fatty acid compositions were studied in kuruma prawn, Penaeus japonicus. The kuruma prawn was fed the purified diets with or without ascidian tunic extract and carophyll pink at the levels of 100, 200, and 400 ppm for 8 weeks. In the experiment diet with ascidian tunic extracts or carophyll pink, the values of daily growth rate were ranged between $1.065\;to\;1.292%$, compared with control group. The content of astaxanthin in kuruma prawn was not significantly affected by the feeding levels of tunic extracts. Feeding of the tunic extracts, on the other hand, increased the kuruma prawn lipid and total cholesterol content, and pigment deposition in concentration-dependent manners without influencing the free astaxanthin concentration of prawn flesh and heads between two feeding groups(200 and 400 ppm). And it was also demonstrated that the dietary astaxanthin was deposited in kuruma prawn body tissue mainly as astaxanthin esters. The results suggest that the best feeding strategy for pigmentation in kuruma prawns is the diets with ascidian tunic extracts at the level of 4g/kg feed (200 ppm) for 8 weeks.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.10 no.3
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• pp.163-170
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• 1977

The present study was carried out to knew the sterol components of U. pinnatifida and their incorporation abilities of $^14C-1-acetate$ injected into it. The results obtained are as follows: 1. The total lipids are classified as hydrocarbon $1.6\%$, pigment and sterol ester $2.5\%$, triglyceri do $3.3\%$, free fatty acid $2.2\%$, free sterol $3.8\%$, chlorophyll $18.8\%$, and polar lipids $ 67.3\%$ 2. The sterol mixture from U. pinnatifida are omposed of cholesterol $3.5\%$, 24-methylene-cholesterol $11.2\%$, fucosterol $85.3\%$. 3. The radioactivities of the lipids classes from U. pinnatifida injected with $^14C-1-acetate$ are distributed 4,648 dpm/ug in total lipid, 2,754 dpm/mg in polar lipids, 373 dpm/mg in chlorophyll, 22,481 dpm/mg in free sterol, 6,520 dpm/mg in free fatty acid, 789 dpm/mg in sterol ester and 358 dpm/mg in hydrocarbon respectively. 4. The specific radioactivities of the sterols are 115 dpm/mg in cholesterol, 147,821 dpm/mg in 24-methylenecholesterol, 20, 887 dpm/mg in fucosterol.

• Korean Journal of Food Science and Technology
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• v.33 no.1
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• pp.1-6
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• 2001

Emulsion products with water soluble protein were exposed under light at $5^{\circ}C$ for 8 days. Peroxide value (POV) was increased significantly at the bigining of storage and 2-thiobarbituric acid (TBA) value also increased until 4 days of storage with increase of the production of carbonyl compounds, suggesting that the condition was reacted different from that of the lipid autoxidation. The reaction was similar to the flavor reversion that usually produced from the bigining of soybean oil oxidation. The reason might be the meat pigment, myoglobin, oxidation and it would be due to the singlet oxygen rather than superoxide anion. When the light was excluded general pattern was similar but the production of oxidation products were smaller than that when the sample was exposed under light. The effect of the singlet oxygen was also smaller which meant that the singlet oxygen produced during emulsion process may affect on the flavor reversion at the bigining of storage. The POV of the emulsion without water soluble protein increase gradually by storage and the results indicated that the degradation rate of the peroxides were lower than the sample with water soluble protein. Especially after 4 days of storage, production of carbonyl compounds were decreased. During storage it would be possible to produce the singlet oxygen and the sensitizer from the plants that can be produced during decoloration of soybean oil may be responsible for it. When the light was excluded the production of oxidation products were reduced at the begining of storage and the effect of quencher also was not detected. Therefore the results indicated that the light can accelerate the lipid oxidation.

• Journal of the Korean Society of Food Science and Nutrition
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• v.14 no.2
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• pp.117-122
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• 1985

The effects of various factors on the color stability of plum nectar were studied. The data showed that pH and temperature were the most important factors affecting the rate of color loss. The concentration of ascorbic acid affected the rate of color loss in plum nectar. Although the color loss could be influenced by the presence of sugars and their degradation products such as 5-hydroxymethyl-2-furfural(HMF), HMF did not accumulate in sufficient amounts during the storage in the plum nectar to affect appreciably the degradation rate. The pigment was very unstable in the fermented juice and its. spectrophotometric spectrum was changed differently from that of natural plum color material. Materials present in plum nectar itself apparently have an appreciable effect on the rate of color loss.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.25 no.1
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• pp.20-26
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• 2015

Ceramic ink-jet printing technology in art tiles, decorated tablewares and other porcelain products has many advantages of fast and precision printing of various images with high efficiency and low cost. For the application to ink-jet printing, ceramic ink requires a stable dispersibility with nano-sized pigments. In this paper, characteristics of pink-red aqueous ceramic ink for ink-jet printing was demonstrated. $CaCr_{0.1}Sn_{0.8}SiO_5$ pigment was synthesized using solid state reaction and deagglomerated using attrition milling. The aqueous ceramic ink contains 10 wt% of the obtained $CaCr_{0.1}Sn_{0.8}SiO_5$ nanopigment with 0.4 wt% of sodium dodecyl sulfate (SDS) as a dispersion agent. Viscosity of $CaCr_{0.1}Sn_{0.8}SiO_5$ aqueous ceramic ink was adjusted using 0.18 wt% of polyvinyl alcohol (PVA) for a suitable jetting from the nozzle. The prepared pink-red ceramic ink showed a good jetting property with formation of a single sphere-shaped droplet after $180{\mu}s$ without a tail and satellite droplet.