• 제목/요약/키워드: natural light

검색결과 1,901건 처리시간 0.028초

Photochromic Behavior and Its Stability of a New Bifunctional Dye Composed of Spirobenzopyran and a Cinnamoyl Moiety

  • Shen Kaihua;Kim Jae Hong;Kim Go Woon;Cho Min Ju;Lee Sang Kyu;Choi Dong Hoon
    • Macromolecular Research
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    • 제13권3호
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    • pp.180-186
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    • 2005
  • A novel bifunctional dye composed of spirobenzopyran and a cinnamoyl moiety was prepared and its photochromic behavior under the illumination of monochromatic UV light was investigated. This colorless bifunctional dye exhibits typical photochromism in both the film and in solution, through the structural and geometrical transformation from spirobenzopyran to merocyanine accompanied by a photocrosslinking reaction between the cinnamoyl moieties. Two kinds of photochemical reaction were selectively achieved by irradiation with monochromatic UV light at wavelengths of 275 and 365 nm, respectively. The effect of the selective photochemical reaction on the photochromism of the dye and its decaying behavior was investigated.

BINDING OF LEAF NUCLEAR PROTEIN EXTRACTS TO LIGHT-RESPONSIVIE ELEMENTS OF cab PROMOTERS OF Arabidopsis thaliana

  • Lee, Hwa-Hyung;Park, Hee-Jin
    • Journal of Photoscience
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    • 제3권2호
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    • pp.85-90
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    • 1996
  • The binding ability of leaf nuclear extracts to the lighbresponsive elements (LREs) of cab promoters of Arabidopsis thaliana has been investigated. The cab promoters were fragmented with restr ction endonucleases into LRE that were identified by Mitra et al. [Plant Mol. Biol. 12, 169179 ( 1989)] and other small fragments. After end labeling with Klenow fragment, the fragments were assayed for binding with the leaf nuclear proteins that were prepared by solubilizing the purified nuclei with 0.5 M ammonium sulfate. The binding ability was assayed by mobility shift assay. To perform successful mobility shift assay, several factors affecting the interaction of protein with DNA were optimized before performing the assay. The LREs had several retardation bands. However, the other promoter fragments from the transcription start site to the far upstream region of the promoters had also retardation bands. No particular relationships could be found between the retardation band distributions and the loci of LRE. It is likely that the light-regulation of cab gene expression may be controlled by the multiple interactions of the regulatory protein factors with DNA motifs.

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Design of LNG fuel tank for a light duty truck and numerical analysis of heat leak to LNG tank

  • 민카쇄바 알료나;김성준
    • 산업기술연구
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    • 제27권B호
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    • pp.65-70
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    • 2007
  • The LNG tank are properly designed to fit with the limited installation space of a light duty truck, Hyundai Porter II. This designed LNG tank has 36 liter capacity, so two LNG tanks installed on Porter II truck allow it to run about 432 km per fueling. It is almost two times greater than CNG mileage for same truck. To analyze the relationship between car acceleration and heat leak for different fuel vapor/liquid ratios, the modified Fortran program "Pro-Heatleak" is used. Computational analysis shows that the relationship between the heat leak and vapor/liquid ratio is linearly inversed. Heat leak increases with increasing of car acceleration when fuel vapor/liquid ratio is less than 0.5 and decreases when fuel vapor/liquid ratio is greater than 0.5. The difference between maximum and minimum heat leak for full tank is about 12 percents. For the fuel vapor/liquid ratio equal to 0.5 heat leak does not depend on car acceleration.

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빈랑자 추출물의 염색성 및 기능성에 관한 연구 (Dyeability and Functional Characteristics of Arecae semen Extract)

  • 김지선;조용석;최순화
    • 대한가정학회지
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    • 제41권7호
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    • pp.13-24
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    • 2003
  • Recently there has been interested in the use of natural dyes in textile applications. Generally natural dyes can exhibit better biodegradability and have a higher compatibility with the environment. In this study, cotton, wool and silk fabrics were dyed with alkali extract of Arecae semen using various mordants, and their dyeabilities were discussed. Additionally the fastness to washing, perspiration, light, rubbing, and drycleaning and UV-B protection rate were also investigated. Cotton, silk and wool fabrics dyed with alkali extract of Arecae semen were colored in reddish yellow tint. The optimum dyeing condition of the colorants extracted from the Alecae semen was three repeated dyeing at $95^{\circ}C$ for 1.5 hrs. The dyed fabrics by using mordanting methods improved the fastness to washing, perspiration and drycleaning, but the fastness to light and rubbing were not increased. The UV-B protection rate of the wool fabrics were increased by dyeing with extract of Arecae semen.

동물성 섬유에 대한 Lac 추출물의 염색성 (Dyeabilities of Lac Extract onto the Silk and Wool Fabrics)

  • 박문영;김호정;이문철
    • 한국의류학회지
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    • 제26권8호
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    • pp.1248-1253
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    • 2002
  • Coocus laccae(Laccifer lacca Kerr), usually known as Lac, is a kind of cocoon which is parasitic on the tree around India and China. It contains the laconic acid of red colored dyes and has been used for cosmetic or natural dyeing prior to the introduction of New World cochineal. Nevertheless, the characterization of lac has not been studied, very little informed. The purpose of this study is to examine the effects of dyeing conditions fur Lac extract, such as pH of dye bath, concentration of Lac exact dyeing temperature and time, to find out the optimum conditions. The results were as follow. 1. The highest K/S values of the silk and wool was shown at PH 3 and PH 4. 2. K/S values of the silk came to nearly the adsorption equilibrium state at 40$^{\circ}C$ and the curve of wool showed a dramatic increase with the increase of temperature. 3. Dyed silk and wool fabrics showed good light fastness without using mordants.

Monte Carlo analysis of LWR spent fuel transmutation in a fusion-fission hybrid reactor system

  • Sahin, Sumer;Sahin, Haci Mehmet;Tunc, Guven
    • Nuclear Engineering and Technology
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    • 제50권8호
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    • pp.1339-1348
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    • 2018
  • The aim of this paper is to determine neutronic performances of the light water reactor (LWR) spent fuel mixed with fertile thorium fuel in a FFHR. Time dependent three dimensional calculations for major technical data, such as blanket energy multiplication, tritium breeding ratio, cumulative fissile fuel enrichment and burnup have been performed by using Monte Carlo Neutron-Particle Transport code MCNP5 1.4, coupled with a novel interface code MCNPAS, which is developed by our research group. A self-sustaining tritium breeding ratio (TBR>1.05) has been kept throughout the calculations. The study has shown that the fissile fuel quality will be improved in the course of the transmutation of the LWR spent in the FFHR. The latter has gained the reusable fuel enrichment level conventional LWRs between one and two years. Furthermore, LWR spent fuel - thorium mixture provides higher burn-up values than in light water reactors.

Bis(3,5-dibromophenyl)dimethylsilane: A useful synthon for organosilicon chemistry

  • Lee, Jong-Dae
    • 통합자연과학논문집
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    • 제15권1호
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    • pp.19-25
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    • 2022
  • The diarylsilyl compound, C14H12Br4Si, was prepared from the reaction of 3,5-dibromophenyllithium with dimethyldichlorosilane, (CH3)2SiCl2, at -78 ℃, can be a good synthon for derivatization to produce efficient host materials for organic light emitting diodes (OLEDs). Crystal structure analysis shows a slight deviation from ideal tetrahedral symmetry around the Si atom, whose conformation is effective in ensuring the maximum separation of the two phenyl rings and the two methyl substituents. The directions of the two aromatic rings are almost perpendicular to each other. The molecule exists as a monomer in the solid state.

Performance Evaluation of Energy Reduction of Light Shelf Applying Punching Plate

  • Choi, Yuchang;Lee, Heangwoo;Seo, Janghoo;Kim, Yongseong
    • KIEAE Journal
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    • 제14권6호
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    • pp.5-13
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    • 2014
  • Various studies on lighting energy savings are conducted, given that lighting energy consumption accounts 23.5% of building energy consumption. Especially, external type light shelf's efficiency is acknowledged; however, its application is limited in Korea, where high rise building ratio is high, due to high wind pressure. This study delves into natural lighting system to cope with wind pressure, and proposes the punching plate-installed light shelf. This study actually draws lighting energy output, according to whether the punching plate is applied through the test-bed, and verifies the effectiveness of the punching plate-installed light shelf. The conclusion is presented below: First) The result of performance evaluation of light shelf with the punching plate in winter solstice showed that the awning area decreased as the opening ratio increased so that the indoor distributed illumination tended to increase, and $-40^{\circ}$ which was advantageous for awning was determined as the proper angle. Second) The light shelf with the punching plate in spring/autumn equinox shows improved lighting according to the angle, and the appropriate angle of light shelf with the punching plate has increased to $15^{\circ}$ and $20^{\circ}$ according to the opening ratio in comparison to $5^{\circ}C$ which is the appropriate angle of light shelf with no punching plate due to the reflection area reduced by the reflecting plate with holes. Third) The result of performance evaluation of light shelf with the punching plate in summer solstice showed that the lighting performance tended to decrease as the opening ratio increased. 4) The light shelf with the punching plate incurs a 50% energy loss in comparison to the light shelf with no punching plate. However, its effectiveness has been proven in the aspects that it can bring a 50% energy saving in comparison to the case with no installation of light shelf and that it can be designed in response to wind pressure on the high floors.

키토산 가교 처리된 면직물의 천연염색에 관한 연구(I) - 울금을 중심으로 - (Natural Dyeing of Chitosan-crosslinked Cotton Fabrics(I) - Turmeric -)

  • 곽미정;권정숙;이신희
    • 한국염색가공학회지
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    • 제20권3호
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    • pp.8-17
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    • 2008
  • For the purpose of standardization and practicability of natural dyeing, the mordanting and dyeing properties of turmeric was studied. In this study, the colorants of turmeric were extracted with boiling water. Chitosan-crosslinked cotton fabrics was dyed with aqueous extract of turmeric and their dyeabilities on the fabrics were studied. Additionally the fastness to washing and light were also investigated. Cotton fabrics were treated with a crosslinking agent epichlorohydrin in the presence of chitosan to provide the cotton fabrics the dyeing properties of natural dye(turmeric) by the chemical linking of chitosan to the cellulose structure. The chitosan finishing and durable press finishing of the cotton fabrics occurred simultaneously in the mercerization bath. The dyeability(K/S), which was obtained by CCM observation, remarkably became increased when the crosslinked chitosan concentration was higher. Dyeability of turmeric was improved on chitosan-crosslinked cotton fabric rather than only cotton fabric, while the saturated dyeing time was 20minutes at $60^{\circ}C$. The hue value indicated greenish yellow with increasing the crosslinked chitosan concentration. And the color fastness to washing and light was almost the same.

하중제한이 기존건물의 옥상조경계획에 미치는 영향 (Influence of Load Limitation on the Roofspace Planning of Existing Buildings)

    • 한국조경학회지
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    • 제26권2호
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    • pp.166-180
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    • 1998
  • In a city where the greenery always lacks landscaping roofs of existing buildings offers a way to solve the problem. But the most serious problem that poses is the matter of load limit. At present most existing buildings have the loading capacity of 200 kg/$m^2$ or less on their roofs. If the natural soil is used the loading capacity is easily surpassed because it simply is too heavy. To alleviate this problem it is realized to introduce the light weight artificial soil. The specific gravity of light soil is 0.65 whereas the natural soil is 1.8 when wet. It is three times lighter than the natural soil, thus eases the burden to the roof. The next problem to be confronted is the plant species to plant. It is possible to plant trees but they soon outgrow the loading capacity by weighing 8 times heavier in 10 years. Therefore shrubs and perennials are suggested to be planted because they don't weigh much even when they reach the mature height. The last problem is the stress put on roofs by the weight of the users. By some unexpected event the crowd gathered on a weak roof can cause the structural damage or even the collapse of the roof. The avoid the possibility of collapse a plaza or big pocket should not be designed in a roof garden because they hold crowd. By following the suggested means the old roofs of existing buildings can turn into the urban oases in the sky.

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