• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.12
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• pp.592-599
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• 2018

The kinetics and thermodynamics of the adsorption of acid blue 40 from an aqueous solution by activated carbon were examined as a function of the activated carbon dose, pH, temperature, contact time, and initial concentration. The adsorption efficiency in a bathtub was increased at pH 3 and pH 11 due to the presence of sufonate ions ($SO_3{^-}$) and amine ions ($NH_2{^+}$). The equilibrium adsorption data were fitted to the Langmuir, Freundlich and Temkin isotherms. The results indicated that the Langmuir model provides the best correlation of the experimental data. The separation factor of the Langmuir and Freundlich model showed that the adsorption treatment of acid blue 40 by activated carbon could be an effective adsorption process. The adsorption energy determined by the Temkin equation showed that the adsorption step is a physical adsorption process. Kinetics analysis of the adsorption process of acid blue 40 on activated carbon showed that a pseudo second order kinetic model is more consistent than a pseudo second order kinetic model. The estimated activation energy was 42.308 kJ/mol. The enthalpy change (80.088 J/mol) indicated an endothermic process. The free energy change (-0.0553 ~ -5.5855 kJ/mol) showed that the spontaneity of the process increased with increasing adsorption temperature.

• Bulletin of the Korean Chemical Society
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• v.31 no.1
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• pp.47-51
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• 2010

A powder, containing 80 percent of blue cobalt aluminate $(CoAl_2O_4)$ crystallites, was synthesized at $210 ^{\circ}C$ using a (metal nitrate-malonic acid-ammonium hydroxide-ammonium nitrate) system. The optimal amount of concentrated ammonia water and initial decomposition temperature were determined for the blue $CoAl_2O_4$ crystallites preparation. Three $CoAl_2O_4$ precursor pastes, corresponding to the various amounts of concentrated ammonia water, were prepared by evaporating the initial solutions in an electric furnace fixed at $80 ^{\circ}C$ under a vacuum of 25 torr. The initial solution was used to dissolve the starting materials. The powder with the maximum content (80%) of blue $CoAl_2O_4$ crystallites was prepared when the prepared precursor was decomposed at $210 ^{\circ}C$. The blue $CoAl_2O_4$ crystallite content in the prepared sample decreased with increasing initial decomposition temperature. For 0.2 mole of the $Al^{3+}$ ion, the chemical compositions of the precursor corresponded to molar ratios of 0.4, 1.40, 2.56 and 2.00 for the $Co^{2+}$ ion, malonic acid, ammonia and ammonium nitrate per mole of the $Al^{3+}$ ion, respectively. The blue $CoAl_2O_4$ crystallite content in the sample decreased with the amount of ammonia deviated from the optimal value. The characteristics of the powders were examined using X-ray diffraction, optical microscopy, Fourier transformation infrared spectroscopy and the Brunauer-Emmett-Teller technique.

• Journal of Sericultural and Entomological Science
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• v.27 no.2
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• pp.40-46
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• 1985

The equilibrium sorptions of C.I. Reactive Blue 19 and C.I. Reactive Blue 19 and C.I. Acid Blue 138 on Silk fibroin were investigated in the range of 50$^{\circ}C$, 70$^{\circ}C$, 90$^{\circ}C$ and to the pH range from 2.0 to 10.5. The results obtained are summarized as follows: 1) The amount of sorption of reactive dye was increased with the decrease of pH in dyeing solution and temperature. The amount of fixation showed the maximum value to pH 8.5 and 70$^{\circ}C$. 2) In acidic region, the sorption behavior of acid dye was similar to that of reactive dye, and Langmuir adsorption constant was increased with the decrease of pH. 3) Langmuir constant of both dyes was decreased with the increase of temperature, while standard affinity was increased. 4) The reaction of both dyes was exothermic and the values of $\Delta$S$^{\circ}$ were positive. 5) It was found that the sorption behavior of dyes against Silk fibroin could be described as Langmuir adsorption and Nernst distribution in lower pH region.

• Journal of Food Hygiene and Safety
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• v.34 no.3
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• pp.296-302
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• 2019

Ganjang-gejang (soy sauce-marinated crab) is a ready-to-eat (RTE) seafood and is also one of the most popular traditional dishes in Korea. It is generally prepared by washing raw blue crabs and then preserving them in soy sauce. Since this process does not involve cooking or any treatment with heat, it is difficult to control the microbiological quality of the final product. Thus, the objectives of this study were to compare the efficacies of various sanitizers in eliminating microorganisms on raw blue crab during the washing step and to evaluate the effectiveness of chitosan on the inhibition of microbial growth in the ganjang-gejang during storage. The raw blue crabs were submerged in chlorinated water (50 mg/L), peracetic acid (40 mg/L), acetic acid (5%) and lactic acid (5%) for 10 min at $25^{\circ}C$, respectively. The blue crabs treated with 5% acetic acid were marinated with soy sauce containing 0.5 and 1% of soluble chitosan, followed by storing them at 4 and $12^{\circ}C$ for up to 30 days. Results show that 5% acetic acid reduced the microbial populations on the blue crabs by 1.5 log CFU/g, which was significantly higher than those of other treatments. Based on these results, 5% acetic acid was selected for the washing step. The microbial populations of all ganjang-gejang samples significantly increased to about 8.0 CFU/g at $12^{\circ}C$ for 7 days. At $4^{\circ}C$, the microbial populations of the products containing 1% chitosan increased by about 2.9 CFU/g for 20 days, which were significantly lower than those (4.2-4.5 log CFU/g) of the products without and with 0.5% chitosan. Thus, these results suggest that 5% acetic acid washing of raw blue crabs and the addition of 1% chitosan in ganjang-gejang could improve the microbiological quality of the final products under refrigerated condition.

• Food Science of Animal Resources
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• v.37 no.2
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• pp.181-190
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• 2017

The aim of this study was to compare the quality and physicochemical characteristics of blue-shelled eggs (BE) and conventional eggs (CE). Proximate composition, quality, pH value, shell color, collagen content, fatty acid composition, total cholesterol, ${\alpha}$-glucosidase inhibition activity, and antioxidation activity were determined. The proximate composition, general qualities, and pH values of CE and BE showed no significant differences, except in moisture composition, weight, and shell thickness. Moisture content and weight of BE were significantly lower than those of CE. However, shell thickness and weight of BE were higher than those of CE (p<0.05). Lightness of BE was significantly higher than that of CE (85.20 vs. 58.80), while redness ($a^*$) and yellowness ($b^*$) of BE were lower than those of CE ($a^*$: -4.75 vs. 14.20; $b*$: 10.45 vs. 30.63). The fatty acid [C18:1n7 (cis-vaccenic acid) and C18:3n6 (gamma-linolenic acid)] contents of BE were significantly higher than those of CE. The total cholesterol contents of BE and CE were similar. DPPH radical scavenging activity of BE was significantly higher than that of CE (40.78 vs. 35.35). Interestingly, ${\alpha}$-glucosidase inhibition activity of whole egg and egg yolk in BE (19.27 and 36.06) was significantly higher than that of whole egg and egg yolk in CE (13.95 and 32.46). This result indicated that BE could potentially be used as a functional food material. Further studies are required to evaluate the specific compounds that affect functional activity.

• Korean Journal of Agricultural Science
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• v.16 no.2
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• pp.201-211
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• 1989

This experiment was carried out to study the practical utility of Mucor rennet in making Blue cheese and to investigate the changes in the level of various nitrogen compounds. 1. The Mucor rennet cheese, the calf rennet cheese and the mixed rennet cheese did not show any significant difference in their yields. 2. The dry matter contents of Blue cheese was increased during the ripening and the levels of Mucor rennet did not have any influence in these respect. 3. The water soluble nitrogen contents of Blue cheese increased during ripening. On 0 day of ripening the Mucor rennet cheese contained water soluble nitrogen than the calf rennet cheese. On 40 days of ripening the mixed cheese contained less water soluble nitrogen than the calf rennet cheese. 4. Non protein nitrogen, peptone amino nitrogen, water soluble protein nitrogen, proteose nitrogen and peptone nitrogen appeared to contain similar levels of water soluble nitrogen. 5. The results of electrophoresis indicated a greater degredation on as-casein and ${\beta}$-casein in the Blue cheese made with Mucor rennet than in those made with calf rennet. On 60 days of ripening the mixed cheese more casein than did the Mucor rennet cheese. 6. The free amino acid contents of the Mucor rennet cheese was higher than the calf rennet cheese at 60 days of ripening.

• The Plant Pathology Journal
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• v.16 no.4
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• pp.236-241
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• 2000

A selective agar medium was developed and tested for the isolation of Acidovorax avenae subsp. avenae, the causal bacterial pathogen of bacterial brown stripe, from rice seeds. The new selective agar medium, designated sorbitol pyroglutamic acid agar (SPA) medium, contained 0.5 g of $K_2$HPO$_4$, 3.0 g of Na$_2$HPO$_4$, 2.0 g of D-sorbitol, 0.2 g of L-pyroglutamic acid, 10.0 $m\ell$ of tween 80, 40.0 mg of victoria blue B, 15.0 g of agar, 150.0 mg of ampicillin and 25.0 mg of vancomycin per litter. Colonies of A. avenae subsp. avenae on SPA medium were smooth, round, convex, shiny, blue and 1.5-2.0 mm in diameter 4 days after incubation at 28$^{\circ}C$. Blue colored colony having dark blue zone was typical type of A. avenae subsp. avenae colonies on the medium. Mean recovery of 8 isolates of A. avenae subsp. avenae on the selective SPA medium was 95.8% in comparison to that on KB medium. The saprophytic bacteria were reduced to 97.9% on SPA medium compared to those on KB medium. Most of other rice seedborne bacteria as well as reported pathogenic bacteria were failed to grow on SPA medium. This medium was highly selective for recovering A. avenae subsp. avenae from rice seed samples, and it could be used to enhance the recovery of this bacterium from rice seed samples, which may be contaminated with large numbers of competing microorganisms.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.3
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• pp.312-319
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• 2017

For high value-added applications of natural blue diatomite, the physical refining process and synthesis of SiC from refined diatomite were investigated. Approximately 30 percent Fe ($Fe_2O_3$) in raw blue diatomite was removed by a particle sieve separation process; the Fe composition for 325 mesh down powder was approximately 2 percent. Although a wet and/or dry magnetic separation process had some influence on the separation and/or refining of Fe composition, the Fe composition in the non-magnetic by-product was approximately 2 percent. Water leaching separation was effective in removing the Fe composition; approximately 40 percent of the Fe in raw blue diatomite was removed. The synthesis of ${\beta}$-SiC by a carbothermal reduction of the $SiO_2$ in the refined diatomite using carbon (graphite, carbon black), the effects of an acid-treatment on removing the Fe, and the specific surface area for the synthesized powder were also investigated. The impurities were mostly eliminated and the specific surface area was increased to $52.5m^2/g$.

• Textile Coloration and Finishing
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• v.22 no.2
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• pp.145-154
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• 2010

An alkalophilic microorganism capable of degrading dyes was developed for the treatment of alkaline dye solution. This strain was identified as Pseudomonas species. Using this microorganism, biological treatment of dye was studied in Erlenmeyer flasks. The characteristics of this microorganism were observed under various incubating-condition such as temperature, pH, nitrogen source, and macronutrients concentration. The removal effciencies of Disperse Red 60 from synthetic wastewater were 33.5 ~ 36.9% at the range of $30{\sim}40^{\circ}C$, and they were 31.1 ~ 36.7% at the range of initial pH 8 ~ pH 10, respectively. The optimal culture medium was found to be 0.25%(w/v) yeast extract, 0.25%(w/v) polypeptone, 0.1%(w/v) $KH_2PO_4$, 0.2%(w/v) $MgSO_4{\cdot}7H_2O$, and 1.0%(w/v) $Na_2CO_3$. In treatment of various dyes using Erlenmeyer flasks, the removal effciencies of Disperse Blue 87, Disperse Yellow 64, Disperse Red 60, Acid Blue 193, Acid Red 138, and Direct Yellow 23 were found to be 76%, 71%, 58%, 93%, 94%, and 90% respectively after 24hrs reaction of alkalophilic strain Pseudomonas sp. YBE-12.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.30 no.1
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• pp.72-78
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• 1997

The levels of reducing sugars, organic acids and fatty acids, known as precursors of major flavors induced from dried sellfish, were analyzed to investigate their behaviors during drying process. Free reducing sugar contents were markedly decreased in all samples by boiling, Its content in Blue mussel and Short-necked calm samples significantly decreased after drying process. Among the eight different organic acids from blue mussel, Short-necked calm and Pacific oyster samples, succinic acid in blue mussel and short-necked calm samples was measured with $74.9\%\;and\;67.4\%$, respectively. In the sample of Pacific oyster, succinic acid content was found to be $38.4\%$, but pyroglutamic acid content was the highest level with $41.6\%$. Contents of organic acids with exception succinic acid were significantly reduced in all three samples of sun-dried or hot-air dried. The content of succinic acid in the samples of sun-dried and hot-air dried pacific oyster reduced to $53.0\%\;and\;44.2\%$, respectively, but relatively small decrease $(29.0\%\;and\;10.0\%)$ was observed in sun-dried and hot-air dried short-necked calm samples, respectively. Content of polar lipid with the major fatty acids profile of C16:0, C16:1, C20:5 and C22:6 was consisted of $59.1\%,\;66.7\%\;and\;42.4\%$, respectively, in blue mussel, short-necked calm and pacific oyster samples and the content of polyene fatty acids was appeared to be $40.5\%,\;48.6\%\;and\;48.9\%$, respectively. Relatively high peroxide value in all boiled-dried products samples was found to be $41.64\~86.80\;meq/kg$ sample. Carbonyl value in boiled-dried products samples was found to be $15.55\~27.99\;meq/kg$, but its value in broiled products samples was significantly high level of $127.6\~136.5\;meq/kg$.