• Title/Summary/Keyword: 변색현상

Search Result 142, Processing Time 0.031 seconds

Basic Characteristics and Application of Modern Dancheong Pigment Jangdanyuksaek (Incarnadine) (현대 단청용 장단육색의 기본 특성 및 사용 기준 연구)

  • Kim, Eun Ji;Chung, Kwang Yong
    • Journal of Conservation Science
    • /
    • v.31 no.4
    • /
    • pp.457-476
    • /
    • 2015
  • This study is expected to present instructions and analysis of Modern Dancheong pigments by its physical characteristics. Search pigments currently used and experiments proper mixing ratio of Jangdanyuksaek(Incarnadine). Samples are made by based on presented a mixture ratio which is less exfoliation, cracks and color change. And put into accelerated weathering test and ultraviolet ray degradation test. As a result in case of Jidang($TiO_2$) Rutile type is superior in discoloration and durability. Rutile type makes color difference remarkably because of oil absorption difference while mixing with Jangdan. Water paints which are used as a alternative present yellowness which means water paints lack in durability. whiting should be taken carefully as it has high brightness after degradation.

Browning end Color Characteristics in Mushrooms (Agaricus bisporus) As Influenced by ionizing Energy (버섯의 갈변 및 색도에 대한 전리에너지의 영향)

  • Kwon, Joong-Ho;Byun, Myung-Woo;Cho, Han-Ok
    • Korean Journal of Food Science and Technology
    • /
    • v.22 no.5
    • /
    • pp.509-513
    • /
    • 1990
  • Browning and color characteristics of stored mushrooms (Agaricus bisporus)following ionizing irradiation were investigated in connection with quality deterioration. The phenolic compounds of stored mushrooms showed a gradual decreasing tendency, while extractable browning pigments apparently rose from around 3days of storage under the conditions of $9{\pm}1^{\circ}C,\;80{\pm}7%$ RH and packaging with a corrugated paper box wrapped up in PE. ${\gamma}-irradiation$ at 2 to 3 kGy resulted in a significant reduction of their changes. Immediately after treatment, irradiated mushrooms were more discolored, i.e. a lower Hunter L value and higher Hunter a and b values than control. However, the subsequent storage for 15 days resulted in a preventive influence of ionizing energy on mushroom discoloration. This beneficial effect of ionizing energy was somewhat higher in the pilei than in the stipes of mushrooms and was found to increase lineally with increasing doses up to 3 kGy.

  • PDF

Photodegradation of Cellulosics(Part II) - Chemical Properties of Irradiated Cotton - (Cellulose의 광분해에 관한 연구(II) - 광조사된 면섬유의 화학적 성질을 중심으로 -)

  • 전경숙
    • Journal of the Korean Society of Clothing and Textiles
    • /
    • v.18 no.1
    • /
    • pp.15-22
    • /
    • 1994
  • The formation of carbonyl group was dominant to other functional groups. Concentrations of both carboxyl and peroxide groups were found to rapidly reach low steady state values that increased slightly with increa-sing temperature and relatice humidity. Since the deg-radation of cellulose samples was in the initial stage and the conversion of glycosidic bonds and hydroxyl groups were very small, it was found that changes in the physical and chemical properties could be fitted to a first-order reaction model.

  • PDF

Effects of Pretreatment and Storage Condition on the Quality of Canned Boiled Oyster (전처리와 저장조건이 굴 통조림의 품질에 미치는 영향)

  • NO Rak-Hyeun;SEONG Dae-Whan;YANG Han-Serb;BYUN Dae-Seok
    • Korean Journal of Fisheries and Aquatic Sciences
    • /
    • v.14 no.3
    • /
    • pp.130-138
    • /
    • 1981
  • Discoloration of canned boiled oysters during storage is one of the serious problems which affect the quality of the products as well as the nutritive value. Usually the factors influencing the quality of canned boiled oysters are the process of pretreatments and the storage temperature of the products. In the present work, the changes of the total chlorophylls and carotenoids in the meat and the viscera of oysters were determined in order to make certain the procedure of the discoloration. In addition, the amino-N and the available lysine as factors of the nutritive value were also checked. In case of treatment with additives, direct addition of syrups containing additives just before seaming or soaking boiled oysters into the solution of additives seemed to have mild effects on retardation of discoloration. The migration of carotenoids from the viscera into the meat was faster than that of chlorophyll resulting in yellowing of the Products preceded greening caused by the chlorophylls. Treatment with $0.5\%\; Na_{2}EDTA\;of\;2.5\%$ brine retarded discoloration and available lysine loss of the Products while sodium-polyphosphate accelerated them. It was probably due to that sodium-polyphosphate could affect the softening or breakdown of the muscle of oysters. But most of all, storage temperature of canned boiled oysters seemed to be the major factor influencing the discoloration and nutritive loss of the products.

  • PDF

Species Identification and Weathering of Wooden Striker on the Divine Bell of King Songdok (성덕대왕신종(聖德大王神鍾) 당목(撞木)의 수종(樹種)과 열화(劣化))

  • Kang, Aekyung
    • Conservation Science in Museum
    • /
    • v.4
    • /
    • pp.71-78
    • /
    • 2003
  • The wooden striker on the Divine Bell of King Seongdeok was examined to identify the species of the wood and the outdoor wood weathering caused by solar light, moisture, temperature and air. The species of the wooden striker was identified to Zelkova serrata. When observed the striker with naked eyes, the results were surface discoloration (graying), cracking and roughness. In order to examine the morphological changes according to deterioration type, the specimen were separated to three part(I, II,III-spot). The I-spot was discolored to gray and at the same time entirely covered with dust. So the observation was impossible. The II-spot was also discolored but its texture could be observed. On it could observe numerous fungal hypae and dirts like dust flown into the cell lumens. The cell wall has been so weakened by weathering that it lost the physical intensity. This have made microchecks and splits on the cell wall. Although fungal hypae covered the cell, they did not result in wood decay. The III-spot, located just 0.5 mm below the surface, was maintaining the natural red-brown color of the wood. Its cell wall was similar to that of sound wood. These changes are different from wood decay, and limited only to the surface of the striker-less than or equal to 0.5 mm below.

Improving Effects of Fructooligosaccharide and Isomaltooligosaccharide Contained in Sponge Cakes on the Constipation of Female College Students (스폰지 케이크에 함유된 프락토올리고당과 이소말토올리고당이 여대생의 변비개선에 미치는 효과)

  • 이미라;이경애;이선영
    • Journal of the Korean Society of Food Science and Nutrition
    • /
    • v.32 no.4
    • /
    • pp.621-626
    • /
    • 2003
  • The aim of this study was to evaluate the effects of 40% sucrose replacement with oligosaccharides (fructo- orisomalto-) in sponge cakes. The 18 female college students were divided into two groups; fructooligosaccharide sponge cake group (FOS) and isomaltooligosaccharide sponge cake group (IMOS). In each group, the subjects received 50 g/d of sponge cake which contained about 8 g oligosaccharides for 2 weeks. The results were as follows: (1) Frequency of stool evacuation tended to increase after 1 week and significantly increased after 2 weeks in both groups. (2) Shape and color of stool did not change in FOS group but the IMOS group showed significant improvement. (3) The stool amounts per defecation were not significantly different in both groups. (4) The time of defecation decreased 50% after 1 week in FOS group and tended to decrease gradually in IMOS group. (5) Consistency of stool was significantly decreased after 1 week in both groups and continuously decreased until 2 weeks. (6) Effort for evacuation and comfort feeling after evacuation were significantly improved only in IMOS group after 2 weeks. (7) Gastrointestinal complaints concerning diarrhea, abdominal pains, nausea, flatulence, loss of appetite and weight and bloating were apparent. The symptoms such as abdominal pains, flatulence, and bloating in FOS group lasted for 2 weeks. However, the complaints appeared only during two or three days in IMOS group. In conclusion, our results suggest that isomaltooligosaccharide was more effective than fructooligosaccharide for preventing constipation because isomaltooligosaccharide worked safely in gastrointestinal lumen.

Weathering Phenomena of the Rocks Constituting the Seoggulam (석굴암을 이루는 암석의 풍화현상)

  • Lee, Sang Hun
    • Journal of Conservation Science
    • /
    • v.8 no.1 s.11
    • /
    • pp.1-9
    • /
    • 1999
  • The present aspect of the Seoggulam is the result of natural weathering of the rocks and influences by mankind. The rocks constituting the Seoggulam is granodiorite of medium and coarse grains which show brown to dark brown weathered surface resulted mainly from chemical weathering of feldspars. It also shows partly milky white or black colors due to influences by weathering products of cement used in the concrete dome and cracks. There are cracks and crack zones with very small cracks which may be formed by strong weathering and influences of shocks during operations of reconstitution and repair. However, for the better conservation, it must be considered to maintain the balances of temperature and moisture, especially relative moisture in places within the room, structural stability, and the influences of vibration made up by some reasons.

  • PDF

Impact Assessment of Flame Retardant on Wooden Building with Dancheong (목조문화재 단청에 방염제가 미치는 영향평가)

  • Kim, Hwan-Ju;Lee, Han-Hyoung;Lee, Hwa-Soo;Chung, Yong-Jae;Han, Kyu-Sung
    • Korean Journal of Heritage: History & Science
    • /
    • v.49 no.2
    • /
    • pp.56-69
    • /
    • 2016
  • Flame resistant treatment has been applied since 1973 for fire prevention in historical wooden buildings, but several problems, such as whitening and discoloration are constantly occurring in some Dancheong, in spite of evaluation criteria. It is supposed that these phenomena are caused by the stability issue of flame retardant, Dancheong production methods, the residue of chemicals, which were applied in the past, building location environments, etc., but no evaluation and cause inspection has been performed. Therefore, this study aims to verify the effect of flame retardant on Dancheong by producing Pseudo-samples and setting spatial and temporal environment conditions. Pseudo-samples of Dancheong were produced using three methods; the method specified in the Standard Specification of Properties; the method, which is generally used in the site and the traditional method. For different environment conditions of pseudo-samples, the areas were classified into a coastal area and an inland area and the places were classified into a sunny place and a wetland. After applying a flame retardant, annual variations were inspected for 12 months and change aspects were observed through scan and regular observation. In annual variation inspection, various variations like whitening, decolorization, dissolution and exfoliation were found and especially, whitening was most dominant. When the effect of flame retardant depending on the production methods was analyzed, whitening occurred in all the three production methods. It is supposed that this is because calcium(Ca) was contained in the coloring material of each production method and it reacted with phosphorous(P) of flame retardant. When the effect of flame retardant depending on the environment conditions was analyzed, whitening occurred more in the coastal area than in the inland area and it reduced in the building in a sunny place, which was constructed using the traditional method. It is supposed that this results from the humidity change and the difference of glue used in each production method. In conclusion, for using a flame retardant containing phosphorous(P), there is a need to check if calcium components including Oyster Shell White were used in Dancheong in advance and to conduct various preliminary studies on place conditions and Dancheong construction conditions.

Digitize color reaction using the optical method (광학적 방법을 이용한 정색반응의 수치화)

  • Kim, A-Hee;Kim, Ji-Sun;Jung, Gu-In;Choi, Ju-Hyeon;Lee, Tae-Hee;Park, Sung-Joon;Jun, Jae-Hoon
    • Proceedings of the Korean Society of Computer Information Conference
    • /
    • 2013.01a
    • /
    • pp.277-279
    • /
    • 2013
  • 본 논문에서는 광학적 방법을 이용하여 정색반응을 정량적으로 측정할 수 있는 방법을 제시한다. 정색반응은 발색, 변색의 현상을 일으키는 화학 변화로 시료 용액에 시약을 더하여 특수한 빛을 나타내게 하여, 물질을 정성적으로 검출하는데 이용된다. 하지만 정색반응 결과로 나타난 색상은 사람마다 색구별이 다르므로 정확한 양을 알 수는 없다. 본 연구에서는 시료의 양에 따라 색상 변화의 미세한 차이를 PICkit Serial Analyzer를 사용하여 색상을 수치화하여 시료의 양에 따른 색의 변화를 정량적으로 측정하였다.

  • PDF

폴리카보네이트 특성 향상을 위한 Al-Si-N 박막의 제작 및 크랙 방지

  • Song, In-Seol;An, Se-Hun;Lee, Geun-Hyeok;Jang, Seong-U;Kim, Dong-Hwan;Han, Seung-Hui
    • Proceedings of the Korean Vacuum Society Conference
    • /
    • 2015.08a
    • /
    • pp.168.1-168.1
    • /
    • 2015
  • 자동차 산업분야에서 차량 경량화의 한 수단으로, 자동차용 유리를 무게가 가볍고 고강도 투명 고분자 소재인 폴리카보네이트로 대체하고자 하는 연구가 이루어지고 있다. 하지만, 폴리카보네이트의 낮은 내 마모 특성과 자외선에 의한 열화 및 변색 현상은 해결해야 할 문제점으로 지적되고 있다. 본 연구에서는, 폴리카보네이트의 내마모 특성을 향상시키기 위해 HIPIMS+ (High Power Impulse Magnetron Sputtering+) 방법을 이용하여 투과율이 확보되고, 고경도 특성을 갖는 Al-Si-N 박막을 증착하였다. 고속증착을 하기 위해 Target에 인가되는 Power를 올리게 되었는데, 열팽창 계수가 큰 고분자 물질인 폴리카보네이트 시료의 온도가 상승하여 증착된 박막과의 열팽창 계수 차이에 의해 박막에 Crack이 형성되는 문제가 발생하였다. 증착되는 Al-Si-N 박막의 공정 압력에 따른 Stress 제어 방법 및 폴리카보네이트 시료의 온도 상승을 막기 위한 알루미늄 구조체를 이용함으로써 박막의 Crack 형성을 억제하고자 하였다. 박막의 Stress를 확인하기 위하여 AFM (Atomic Force Microscope)과 OM (Optical Microscope)을 이용하여 분석하였고, 박막의 경도는 Knoop ${\mu}$-hardness tester를 사용하여 측정하였다. Al-Si-N 박막 경도는 Si at.%/(Al at.% + Si at.%) 비율이 16%에서 33 GPa의 경도를 갖는 것을 확인하였다. UV-Vis Spectrometer를 이용하여 투과율을 측정한 결과, 400-700 nm 파장의 가시광 영역 평균 투과율은 80%로 측정되었다.

  • PDF