• Korean Journal of Environmental Agriculture
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• v.30 no.4
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• pp.414-418
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• 2011

BACKGROUND: Plastic mulches widely used in raised-bed culture mainly to conserve water, control weeds and raise soil temperature. The most widely used plastic mulch colour is black. Reflective red and far-red light can affect on growth and yield of various vegetable crops. Objectives of this study were to investigate the characteristics of reflective light of black and red plastic mulches, and to evaluate the reflective red and far-red light on the quality characteristics and yield of the Oriental melon (Cucumis. Melo L.) and tomato (Lycopersicon esculentum L.). METHODS AND RESULTS: Oriental melon and tomato were cultivated over the reflective red and black plastic mulches in plastic house. Reflected red and far-red light over the red plastic mulch were 2.6 times higher than those of black plastic mulch. Red to F-Red ratio of black plastic mulch, red plastic mulch and sunlight were 1.14, 0.93 and 1.16 respectively. Intensity of reflected red and far-red light over red plastic mulch were highest at surface height of 30 cm. The higher the height of the surface decrease the intensity of far-red light. Accordingly, Red to F-Red ratio were increased. Reflective red plastic mulch increased the weight of fruit and content of sugar in Oriental melon and tomato. CONCLUSION(s): Yield of Oriental melon over reflective red plastic mulch was higher than that of black plastic mulch. These results suggested that reflected red and far-red light over the red plastic mulch affected allocation of photosynthate in growing Oriental melon.

• Analytical Science and Technology
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• v.32 no.3
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• pp.77-87
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• 2019

High viscosity carbon black dispersions are used in various industrial fields such as color cosmetics, rubber, tire, plastic and color filter ink. However, carbon black particles are unstable to heat due to inherent characteristics, and it is very difficult to keep the quality of the product constant due to agglomeration of particles. In general, particle size analysis is performed by dynamic light scattering (DLS) during the dispersion process in order to select the optimum dispersant in the carbon black dispersion process. However, the existing low viscosity analysis provides reproducible particle distribution analysis results, but it is difficult to select the optimum dispersant because it is difficult to analyze the reproducible particle distribution at high viscosity. In this study, dynamic light scattering (DLS) and asymmetrical flow field-flow fractionation (AsFlFFF) analysis methods were compared for reproducible particle size analysis of high viscosity carbon black. First, the stability of carbon black dispersion was investigated by particle size analysis by DLS and AsFlFFF according to milling time, and the validity of analytical method for the selection of the optimum dispersant useful for carbon black dispersion was confirmed. The correlation between color and particle size of particles in high viscosity carbon black dispersion was investigated by using colorimeter. The particle size distribution from AsFlFFF was consistent with the colorimetric results. As a result, the correlation between AsFlFFF and colorimetric results confirmed the possibility of a strong analytical method for determining the appropriate dispersant and milling time in high viscosity carbon black dispersions. In addition, for nanoparticles with relatively broad particle size distributions such as carbon black, AsFlFFF has been found to provide a more accurate particle size distribution than DLS. This is because AsFlFFF, unlike DLS, can analyze each fraction by separating particles by size.

• Journal of the Korean Ceramic Society
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• v.41 no.2
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• pp.176-181
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• 2004

EAF (Electric Arc Furnace) dust is classified as special wastes containing heavy metal contaminants may cause to damage an environment such as underground water contamination if they were not treated properly. For reutilizing the EAF dust, the porous body was made from EAF dust/clay composition system, and analyzed pore characteristics. It was found that a light-aggregate body was made up two different microstructures. One was non-black and dense microstructure which located near surface, and the other was black and porous microstructure (black coring) which located inner part. For systematizing the relationship of the black-coring area and the bloating degree, we defined the Ic(core index) and Is(shell index). It was found that the optimal bloating conditions of artificial light-weight aggregate were more than 0.5 of Ic and 0.4 of Is.

• Textile Coloration and Finishing
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• v.29 no.4
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• pp.276-283
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• 2017

The aim of this study is to develop an effective dyeing process for black color on the silk fabrics, using natural Indigo, Madder, Amur cork tree, Alder, Logwood, and Gallnut. All natural dye materials were water-extracted, concentrated, and freeze-dried. Seven different processes were carried out and the color differences(${\Delta}E$) of black color with each process from the chemical black dyed fabric were compared. The light, washing, and rubbing fastness were evaluated. The black dyeing of the silk fabrics was well carried and excellent black color was obtained in every methods. The profound black color could be obtained by the subtractive mixture of the three primary colors of red, yellow, and blue in the order of indigo(blue) - amur cork tree(yellow) - madder or lac(red). Black color was efficiently obtained by iron mordant when logwood or alder fruit was used. The color difference(${\Delta}E$) from the black color with chemical dyestuff was the lowest in the indigo - amur cork tree - lac - iron method. Light fastness and washing fastness were excellent in all dyeing processes, showing grade 5. The fastness to rubbing was excellent as shown grade 5 in the dry samples of logwood - iron process and alder fruit - iron process.

• 한국정보디스플레이학회:학술대회논문집
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• 2002.08a
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• pp.1047-1050
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• 2002

Generally, the Black Matrix of CRT is formed by the application of photoresist and black material separately. We have developed the simple process for black matrix of CRT. We used the black photoresist, It made it possible that the formation of Black Matrix by application of the light exposure and development only once.

• Journal of Korean Society for Atmospheric Environment
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• v.28 no.4
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• pp.411-422
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• 2012

Ground-based in-situ measurements of aerosol optical properties at Gosan climate observatory have been analyzed to investigate the optical contribution of Asian dust and polluted particles on light absorption in springtime 2011. During the Asian dust episode, the contribution of Asian dust particle to aerosol absorption coefficient estimated about 45% at 370 nm and about 23% at 520 nm. Especially, black carbon in dust plume contributes about 48% to aerosol light absorption at 520 nm since the airmass are transported from the Gobi and inner Mongolia deserts, and this airmass comes across the northeastern coast of China, near the Shandong Peninsula. In pollution case, the contributions of dust particle and black carbon to aerosol absorption coefficient estimated about 41% and 11% at 370 nm, respectively. However, pollution case shows the highest light absorption of 48% for brown carbon at 370 nm, which indicates the significantly high mass concentration of organic carbon ($6.3{\pm}2.2{\mu}g\;m^{-3}$) in pollution plume can contribute to the increase of light absorption at near-UV spectral region.

• Journal of the Korean Society of Costume
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• v.37
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• pp.231-252
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• 1998

Since the costume directly express human mental and emotional status, colors of costume can be valuable data to grasp the spirit of the times. Black is noticeably used in modern fashion and the study for black costume is very useful to understand modern fashion. There-fore the study mainly approaches the black costume, finding its background of appearance and symbolism, reviews the symbolism and formality of black expressed in the field of paint-ing and design beyond the fashion, and compar-es to fashion. The study result of the thesis is as follows ; First, black as a color is a one to light other neighboring colors, while it is a static, con-tractible and outstandigly attractived color. Second, black color traditionally symbolizes death, earth, air, North and inferior level and in the painting, it symbolized death, despair, fantastic world and the expression of pent-up self, while cities have been symbolized in the black printing in modern times. In the design, black has appeared with the industrial society, which symbolizes functionality and modernity. Third, black in the fashion design was symbolized death, sternness simplicity, modernity, sex, resistance and so on. Death became conspicious by a religious factor since the old times, sternness was influenced by Spanish fashion in the 16th century, simplicity by Dutch fashion in the 17th century and modernity by Baudelaire dandyism and Chanel little black dress, while sex and resistance were urged to the modern times by teenage inferior culture and stickiness to sex. Fourth, the formative features of black costume prefer simplicity, tightness and bareness in form, and in material, usually used glancing materials changed by the effect of light, lace, see-through fabric and matte one with depth. As a result, the black color is summarized to symbol death, expression of self and modernity. It is not a color of emotion but of mentality and artificial one against nature. Black color in fashion gets a strong power to express self in the symbolic aspect and draws a higher attention on human body than the fashion itself. By these features, black costume will be continuously prefered in spite of changes of the fashion.

• Journal of Astronomy and Space Sciences
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• v.19 no.1
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• pp.25-30
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• 2002

Black hole binary candidates are known to be composed of a black hole with 10 $M_{\odot}$ and a K or M type companion. Because the companion is believed to fill the Roche lobe that is very aspherical, the light curves of black hole binaries are characterized by an ellipsoidal variation. It has been known that the ellipsoidal light curves exhibit asymmetric maximum brightness at the orbital phases 0.25 and 0.75, which has been attributed to star spots or the hot impact points of the accretion flow on to the accretion disk around the black hole. In this paper, it is pointed out that the special relativistic beaming effect contributes to the asymmetry of several percent often observed in the light curves. The typical orbital velocity 400 km $s^{-1}$ observed in black hole binaries may induce the temperature difference $\DeltaT/T$ ~ 1/400 of the late type companion star in the observer`s rest frame, because of the special relativistic Doppler beaming effect. This difference in temperature can result in several per cent of brightness sensitively dependent on the wavelength band, which is comparable to what has been observed in most black hole binary candidates. Considering the significant contribution of the special relativistic Doppler beaming effect, we conclude that the estimation of the sizes and temperatures of the star spots or the hot impact point needs serious revision.

• Applied Microscopy
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• v.26 no.3
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• pp.277-291
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• 1996

The structures of the egg envelope in fertilized eggs of three species of characidae, head and tail light fish (Hemigrammus ocellifer), black tetra (Gymnocorymbus ternetzi), and buenos aires tetra (Hemigrammus caudovittatus) were studied using light and electron microscopes. The fertilized eggs in all species were colorless, transparent, spherical and non-floted type. The egg envelopes have a single micropyle resembling the pathway of sperm in the area of the animal pole. The micropyle was surrounded by protruded lines of the egg envelope in a radiated form. Egg envelopes of fertilized eggs in both head and tail light fish and buenos aires tetra consisted of three distinct layers; an outer layer, a middle layer and an inner layer. And that of blacktetra consisted of two layers; an outer layer and an inner layer. Also, an outer layers of both head and tail light fish and black tetra were adhesive types but, in that of buenous aires tetra was non-adhesive type. An outer surface of egg envelope in black tetra was arranged by pores regularly. In that of head and tail light fish and buenos aires tetra have a rough side. An inner layer of egg envelope in fertilized eggs consisted of lamellae alternating with interlamellae of lower electron density; an inner layer of fertilized eggs in head and tail light fish consisted of three layers, that of black tetra was four layers, and that of buenos aires tetra was five layers.

• Proceedings of the Korean Society of Medical Physics Conference
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• 2002.09a
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• pp.272-274
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• 2002

The contribution of light in high-energy film dosimetry was examined using six commercially available solid water substitute phantoms. As six commercially available phantoms; RMI-451, Mix-DP, WE211, WE211-Black, PMMA and PMMA Black were evaluated in this study. It is difficult to evaluate the contribution of Cerenkov radiation and the optical permeability to the relative and/or absolute dosimetry using unpacked film in these phantoms. Therefore the contribution of Cerenkov radiation was estimated by the comparison between film densities in the shielded side (shutting off the light) and unshielded sides on a phantom. The effect of optical permeability was measured under ambient light by the time scale method. The results suggest that the use of black colored phantoms may improve the accuracy of dose measurement in film dosimetry.