• Applied Chemistry for Engineering
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• v.24 no.2
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• pp.165-170
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• 2013

An external gelation method in place of an internal gelation method applied to the fabrication process of an intermediated compound of Uranium Oxy-Carbide (UCO) kernel spheres for Very High Temperature Reactor (VHTR) fuel preparation is under development in Korea. For the preliminary experiments of the UCO kernel sphere preparation using an external gelation method, the carbon black dispersion experiments were carried out using a simulated broth solution. From the selection experiments of various kinds of carbon black through dispersion experiments in a viscous metal salt solution, Cabot G carbon black was selected owing to its dispersion stability, and the homogeneous dispersing state of carbon black particles in our system. For the effective dispersion of nano-size aggregated carbon black particles in a high viscous liquid, the carbon black particles in a metal salt solution were first de-aggregated with ultrasonic force. The mixed solution was then dispersed secondly by the use of the extremely high-speed agitation with a mechanical mixer of 6000 rpm after feeding the Poly Vinyl Alcohol (PVA) in the solution. This results in the broth solution with good stability and homogeneity alongside no further changes in physical properties.

• Journal of Korean Society of Environmental Engineers
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• v.32 no.6
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• pp.547-554
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• 2010

In this study, new manganese oxide (i.e., black-birnessite) particles with nanostructures were prepared and its physico-chemical properties and oxidative-transformation efficiency on 1,4-naphthoquinine(1,4-NPQ) in the presence of reactive mediator was investigated. The results were also compared with that of the manganese oxide (i.e., brown-birnessite) particles synthesized by classical McKenzie method. Analysis of XRD and SEM data show that the particles are a single phase corresponding to a birnessite-based manganese oxide with cotton ball-like shapes containing nanofibers. In batch experiments, removals of 1,4-NPQ by the black-birnessite follows pseudo-first-order kinetics and the rate constant values obtained are greater about 2.3 times than that of the brown-birnessite in spite of its lower surface area (41.0 vs 19.80 $m^2/g$). The results can be explained by the higher crystallinity and nano structured features of the back-birnessite particles, which give higher reactivity for the removals of the quinone compound. HPLC analysis of the reaction products confirmed that the balck-birnessites removed 1,4-NPQ through cross-coupling reaction in the presence of catechol as a reactive mediator.

• Polymer(Korea)
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• v.25 no.1
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• pp.98-107
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• 2001

Dielectric properties and shape memory characteristics of SBS composites filled with carbon black as conductive filler and (Ba,Ca)$(Sn,Ti)O_3$ or $SrTiO_3$ as dielectrics were investigated for the development of phantom model. SBS/carbon black composite showed an increment of complex dielectric constant with increasing the content of carbon black and the frequency dependence that the dielectric constant decreases with the frequency. The complex dielectric constant and the conductivity of SBS/carbon black/dielectrics composites increased with the increase of dielectrics and the characteristics of the frequency dependence also occurred by the effect of carbon black. Phantom materials with the dielectric properties and the conductivity corresponding to human tissues for the measurement of specific absorption rate(SAR) within the frequency range of current mobile phones(775MHz~2GHz) could be developed by adjusting the composition ratios of carbon black, dielectrics and SBS and by controlling the characteristic of frequency dependence of composite. From thermomechanical cycling test good shape recoverability could be obtained in SBS composite even though the residual strain was increased by the effect of filler.

• Korean Journal of Food Science and Technology
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• v.39 no.4
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• pp.390-399
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• 2007

Moru (wild grape), blueberry, bokbunja (blackberry), and blackcurrant were mixed with domestic Campbell Early grapes to improve the quality of domestic wines made from the grape. The color of the Campbell wine was greatly darkened by mixing it with the fruits. The L-value of the wine color during fermentation was lowered from 34 to $6{\sim}13$ by mixing it with 20% bokbunja or blackcurrant. In addition, the a-value of the wine color during fermentation was lowered from 54 to $36{\sim}46$ by mixing it with 20% bokbunja or blackcurrant. The mixing of moru or blueberry also lowered the L- and a-values, but this darkening effect was not higher than that of the Campbell wine that was mixed with bokbunja and black currant. The polyphenol concentration of the wine was greatly increased by mixing it with black currant and bokbunja. The blackcurrant mixed wine had a polyphenol concentration as high as 1.87 mg/mL, whereas the wine made from the Campbell Early grapes alone contained only 1.02 mg/mL of polyphenols after 15 days of fermentation. A sensory evaluation showed that the quality of Campbell wine was the least favorable among different grapes, but its quality was greatly improved by mixing it with bokbunja, black currant, and moru.

• Korean Journal of Plant Resources
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• v.31 no.2
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• pp.136-148
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• 2018

The study was performed to investigate basic tree growth and fruit characteristics of 'Nero' black chokeberry (Aronia melanocarpa) depending on the different cultivation regions and altitudes in 2014, 2015. Tree growth and change of developmental stages of 'Nero' were similar regardless of meteorological environment of the four cultivation regions (Danyang, Okcheon, Yeongdong, and Geumsan) in 2014. Fruit characteristics of 'Nero' were significant differences in berry weight and anthocyanin content among the four orchards due to difference in cultivation techniques and relatively wide daily temperature range just before harvest, respectively. Tree growth and change of developmental stages of 'Nero' grown at the two orchards with different altitudes appeared to be similar during the successive years 2014 and 2015. Soluble solids content of the berries cultivated at low altitude (117 m) was higher than at high altitude (342 m). Acidity showed an inverse pattern with soluble solids content. Anthocyanin content increased progressively until at the middle of August, 2014-15 and then it decreased. Our results showed that black chokeberry is a species adaptive to the domestic environment as there were no differences in tree growth and change of developmental stages of 'Nero'. Considering fruit quality of black chokeberry such as soluble solids content, acidity, and anthocyanin content, our results suggest that optimal harvest period of black chokeberry 'Nero' is August 8 to 19.

• Food Science and Preservation
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• v.19 no.2
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• pp.263-270
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• 2012

The chemical components and anti-oxidant activities of black currant were investigated. The pH, soluble solid and total acidity values were 3.36, 15.11 $^{\circ}Brix$, and 1.65%, respectively. The Hunter L, a, and b values were 18.20, 5.13, and 1.08, respectively. The proximate compositions were as follows; moisture, 77.64%; nitrogen free extract, 17.41%; crude fiber, 3.08%; crude protein, 1.28%; crude ash, 0.31%; and crude lipid, 0.28%, respectively. The mineral elements were K (177.36 mg/100 g), P (54.74 mg/100 g), and Ca (26.45 mg/100 g). The free sugar components were glucose (7.71%) and fructose (5.88%). The amino acid contents of the black currant were very rich in glutamic acid (105.73 mg/100 g) and deficient in cystine (5.29 mg/100 g). The ascorbic acid and total phenolic contents were 112.19 mg/100 g and 34.48 mg GAE/g, respectively. The ABTS and DPPH radical scavenging activity levels were 99.48% and 89.03% at the 10 and 1.25 mg/mL concentrations. The reducing power and FRAP of the black currant were dose-dependent. Thus, black currant can be an effective source of functional food substances, i.e., natural anti-oxidants.

• Elastomers and Composites
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• v.44 no.3
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• pp.336-342
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• 2009

We measured shear viscosity of polystyrene (PS) and poly(butyl methacrylate) (PBMA) particles, with a capillary rheometer, prepared by suspension polymerization with 1.0 wt% hydrophobic silica as a stabilizer by varying the initiator concentration at $75^{\circ}C$. PS particles with weight average molecular weight of 66,500 g/mol displayed a Newtonian behaior at low shear rates at $190^{\circ}C$. With increasing molecular weight, PS particles showed shear thinning over the entire range of shear rates. For PBMA particles, steady shear measurement was carried out at $170^{\circ}C$. PBMA particles with weight average molecular weight of 156,700 g/mol showed a Newtonian behaior only at low shear rates. PBMA particles also showed shear thinning with an increase in molecular weight and its pattern similar to that of PS. When carbon black was incorporated into PS and PBMA polymers, steady shear measurement was conducted at $170^{\circ}C$. An increase in carbon black concentration in PS and PBMA composite particles exhibited a progressive increase in shear viscosity. The increase in shear viscosity, however, was less pronounced compared to an increase as a function of molecular weight. Preparing PS composites containing carbon black by internal mixing resulted in an increase in shear viscosity. Its increase, however, was found to be less than that shown in PS composite particles. We speculate that this is caused by an enhanced dispersion of carbon black particles with an internal mixer. Yield behavior was not observed in any of the samples we selected in this experiment.

• Elastomers and Composites
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• v.41 no.3
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• pp.194-204
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• 2006

The effects of the particle size and the structure of carbon blacks on the friction and the wear behavior of filled natural rubber were investigated in this study. The particle size and the structure of carbon black had a significant effect on the wear rates and the worn surface pattern, and the effect of them on abrasion resistance should be considered for the optimum design of desired wear properties. Ten carbon blacks with various sizes and structures are mixed with natural rubber in order to investigate the effects on the wear rate ($W_R$). The friction and the wear behavior were examined by self-made blade type friction-wear abrader, and the ,elation with characteristic parameter (${\psi}=\sqrt{{N_2^2}+{DBP^2}}$), obtained from the particle size and the structure, was studied. The wear rate ($W_R$) had a Power Law relation with the frictional work ($W_f$) and it was inversely proportional to the characteristic parameter of carbon black. It means that smaller particle size and better structure development of carbon black resulted in improved abrasion resistance.

• Resources Recycling
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• v.26 no.4
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• pp.71-78
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• 2017

This study investigated the recovery of metallic aluminium in the black dross generated from used beverage can recycling process with crushing mechanism such as compression and impact. The as-received Al black dross had a spherical shape, and its size was about 10~40 mm. Also, The X-ray diffraction pattern showed that the main contents of black dross are composed of halite (NaCl), sylvite (KCl), spinel ($MgAl_2O_4$) and corundum ($Al_2O_3$). A metallic aluminium recovery test was performed using jaw crusher and hammer mill having different crushing mechanism. It was analysed that Jaw crushing process can separate into metallic aluminium and non metallic constituents. However, hammer milling process shows significant difference on the separation results. It was found that jaw crushing process was effective for recovery of metallic aluminium in the black dross than that of hammer milling process.

• Journal of Convergence for Information Technology
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• v.12 no.5
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• pp.183-193
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• 2022

The purpose of this study is to analyze the effect of black consumer behavior perception on the anger expression and turnover intention of beauty workers. For data collection, the final 392 copies were used by distributing questionnaires to 400 people for three months from November 1, 2021 to January 31, 2022, centering on beauty service workers in Seoul, Gyeonggi, and Incheon. For data analysis, SPSS 25.0 program was used. Frequency analysis was performed to identify demographic characteristics, and factor analysis and reliability analysis were performed to understand the validity of the measurement tool. Correlation analysis, A regression analysis was performed. As a result of the analysis, the transient and deterrence of black consumers had a positive (+) effect on anger expression, anger suppression, and turnover intention, and anger expression and anger control had a positive (+) effect on turnover intention. Therefore, it is necessary to raise excessive problems of black consumers or eradicate forced services, and it is believed that proper customer response methods and programs for stress relief should be provided by members.