• Korean Chemical Engineering Research
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• v.54 no.2
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• pp.255-261
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• 2016

Adsorption experiments of Acid Yellow 14 dye using activated carbon were carried out as function of adsorbent dose, pH, initial concentration, contact time and temperature. The equilibrium adsorption data were analyzed by Langmuir, Freundlich and Temkin isotherm model. The experimental data were best represented by Freundlich isotherm model. Base on the estimated Freundlich constant (1/n=0.129~0.212) and Langmuir separation factor ($R_L=0.202{\sim}0.243$), this process could be employed as effective treatment method. The heat of adsorption of Temkin isotherm model was 5.101~9.164 J/mol indicated that the adsorption process followed a physical adsorption. Adsorption kinetics experimental data were modeled using the pseudo-first-order and pseudo-second-order kinetic equation. It was shown that pseudo-second-order kinetic equation could best describe the adsorption kinetics. Base on the negative Gibbs free energy (-4.81~-10.33 kJ/mol) and positive enthalpy (+78.59 kJ/mol) indicate that the adsorption is spontaneous and endothermic process.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.55 no.3
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• pp.267-277
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• 2022

This study investigated changes in the physicochemical and microbiological properties of fermented fish sauces based on the pacific sand lance Ammodytes personatus during fermentation according to rice koji treatments and salt contents. In total, six fish sauces were prepared, with rice koji treatment for 24 or 72 h before salt addition, and salt contents of 10 or 20%, including two controls to compare the response to different salt contents without koji treatment. The initial pH values of the sauces with koji treatments were notably lower than those of the controls. Over the 10 months of fermentation, the amino nitrogen contents of the sauces with 10% salt were higher than those with 20% salt, while the volatile base nitrogen value was also increased. In the microbial community, the initial numbers of lactic acid bacteria and mold were higher in the sauces with koji treatment than in the controls. After 8 months of fermentation, the free amino acid and organic acid contents were higher in the sauces with koji treatment than in the controls. Although the fermentation rate was affected to a greater extent by salt contents, the rice koji treatment also exerted a positive effect on the acceleration of fermentation.

• Corrosion Science and Technology
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• v.13 no.3
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• pp.87-94
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• 2014

Recently, the application of bending products has been increased since the industries such as automobile, aerospace, ships, and plants greatly need the usage of pipes. For facility fabrication, bending process is one of key technologies for pipings. Induction heat bending process is composed of bending deformation by repeated local heat and cooling. Because of local heating and compressive strain, detrimental phases may be precipitated and microstructural change can be induced. This work focused on the effect of induction heat bending process on the properties of ASME SA312 TP316 stainless steel. Evaluation was done on the base metal and the bended areas before and after heat treatment. Microstructure analysis, intergranular corrosion test including Huey test, double loop electropotentiokinetic reactivation test, oxalic acid etch test, and anodic polarization test were performed. On the base of microstructural analysis, grain boundaries in bended extrados area were zagged by bending process, but there were no precipitates in grain and grain boundary and the intergranular corrosion rate was similar to that of base metal. However, pitting potentials of bended area were lower than that of the base metal and zagged boundaries was one of the pitting initiation sites. By re-annealing treatment, grain boundary was recovered and pitting potential was similar to that of the base metal.

• Applied Chemistry for Engineering
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• v.9 no.6
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• pp.920-923
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• 1998

In this work, the adsorption characteristics of the activated carbon treated with 30 wt. %HCl and 30 wt. % NaOH were investigated. The acid and base values were determined by Boehm's method and the surface area and porosity was measured by BET-method with $N_2$-adsorption. Also, the adsorption characteristics of the activated carbons treated with acid and base chemical solutions were investigated with $CO_2$ and $NH_3$-adsorption. From which, relatively different adsorption behaviors of the modified activated carbons were observed in the amounts of $CO_2$ and $NH_3$ adsorptions, even though the physical surface structures of the activated carbons, such as specific surface area, pore size and pore volume, were not significantly changed.

• Journal of Veterinary Science
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• v.23 no.6
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• pp.85.1-85.11
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• 2022

Background: Neonatal calf diarrhea is a major problem in the cattle industry worldwide. Rotavirus and Cryptosporidium parvum are the primary causative agents, especially during the first three weeks of the calf's life. Objectives: This study investigated the differences in acid-base, electrolytes, and biochemical parameters of diarrheic calves with infection of either rotavirus or C. parvum. Methods: A total of 61 Korean native calves (≤ 20 days old) were divided into two groups based on rotavirus or C. parvum infections: rotavirus infection (n = 44) and C. parvum infection (n = 17). The calves with at a specific blood pH range (pH 6.92-7.25) were chosen for comparison. The acid-base, electrolyte, chemistry, and serum proteins were analyzed, Further, fecal examinations were performed. Results: Compared to C. parvum-infected calves, the rotavirus-infected calves showed lower levels of total carbon dioxide, bicarbonate (HCO₃^-), anion gap, total protein, and albumin/globulin ratio, and significantly lower levels of potassium, globulin, and α2-globulin (p < 0.05). The C. parvum-infected calves (r = 0.749) had stronger correlations between pH and HCO₃^- than the rotavirus-infected calves (r = 0.598). Compared to rotavirus-infected calves, strong correlations between globulin and α2-globulin, α2-globulin and haptoglobin were identified in C. parvum-infected calves. Conclusions: This study is the first to investigate acid-base, electrolyte, and biochemical parameters in calves in response to infections of rotavirus and C. parvum. Although rotavirus and C. parvum cause malabsorptive and secretory diarrhea in similar-aged calves, blood parameters were different. This would help establish the diagnostic and treatment strategies.

• Korean Journal of Poultry Science
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• v.22 no.3
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• pp.133-144
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• 1995

One metabolism trial(Experiment I) and another respiration trial(Experiment II) were conducted to investigate the effects of dietary fiber supplementation(20% wheat bran) on the water balance, blood acid-base balance, body temperature, and metabolic rate of heat-stressed adult roosters. In Experiment I, twenty 20-wk-old SCWL roosters(BW 1.6 kg) were randomly alloted to 4 treatments with 5 birds per treatment and one per replicate. The 4 treatments were consisted of two temperature(21~22˚C vs. 34~35˚C) and two dietary fiber treatment(0% and 20% wheat bran), making Experiment I a 2x2 factorial. After 4 d of preliminary period, birds we subjected to 3-d collection period. Sixteen 20-wk-old SCWL roosters(BW 1.6 kg) were employed Experiment H, with two temperature(21~22˚C vs. 34~35˚C) and two wheat bran levels(0% and 20%). Brids were housed in individual metabolism cages under normal temperature(21~22˚C), at fed one of the experimental diet. After 4 d of preliminary period, a respiration trial with open-circuit gravimetric respiratory apparatus was carried out for each bird for 6 h, one by one, normal(20~21˚C) and hot(34~35˚C) temperatures. The ANOVA test and comparisons among treatment means were done at 5% probability level for both experiments. Results obtained from Experiment I and, II were summarized as follows, 1.The amounts of DM intake and excretion were significantly(P<.05) decreased by heat stress. The DM intake was not affected by the addition of 20% wheat bran, however, the amount of DM excretion was significantly increased by the high fiber diet. Thus, the DM metabolizability decreased significantly by the addition of 20% wheat bran. 2. The heat-stressed roosters increased the water intake and excreta moisture content significantly. Although not significant, the water intake tended to increase in roosters fed the 20% wheat bran diet. 3. The amounts of total water input and evaporative water loss were increased significantly by heat stress, and the addition of 20% wheat bran did not exert any influence on the total water input and evaporative water loss. However, roosters fed the 20% wheat bran diet increased the excreta water output significantly. 4. Neither the heat stress nor the dietary fiber did affect the blood pH, pCO2, and HCO$_3$- significantly. 5. The body temperature increased significantly by the heat stress. However, the high fiber deit failed to decrease the body temperature. 6. The heat-stressed roosters decreased the 02 consumption and C0$_2$ production, and increased the evaporative water loss significantly. However, the high fiber diet did not exert any infulence in this regard. It appears that the beneficial effect, if any, of high fibrous diet during heat stress episode may be due to the increased heat loss through the enhanced excreta water.

• Carbon letters
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• v.13 no.2
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• pp.61-72
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• 2012

Dye removal from waste water via adsorption by activated carbons (ACs) developed from agricultural wastes represents an ideal alternative to other expensive treatment options. Physical and chemical ACs were prepared from rice husks. The textural properties of the ACs were characterized by Brunauer-Emmett-Teller-$N_2$ adsorption and scanning electron microscopy. The chemistry of the carbon surface was investigated by Fourier transform infrared spectroscopy, base and acid neutralization capacities, pH of the active carbon slurry, and $pH_{pzc}$. The adsorption capacities of the ACs for the basic dye (methylene blue) and acid dye (acid green 25) were determined using parameters such as contact time, pH, and temperature. NaOH-ACs showed the highest surface area and total pore volume, whereas steam-ACs showed the lowest ones.

• Journal of the Korean Society of Tobacco Science
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• v.23 no.1
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• pp.40-44
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• 2001

This study was carried out to investigate relationship between contents of moisture and chemical components in burley tobacco after heat treatment. Initial moisture contents of burley tobacco was 32% after cutting and casing. Burely cut tobaccos were treated at various temperature(10$0^{\circ}C$, 13$0^{\circ}C$, 145$^{\circ}C$ and 16$0^{\circ}C$) and time(0, 5, 10, 15, 20 and 30 min) in mechanical convection oven. Moisture contents of burley tobacco after heat treatment were in the range of 1.9% to 18.4%. Relationship between moisture contents and total sugar, pH, total volatile base, ammonial, L value of color, nicotine, nornicotine, and $\beta$-nicotyrine contents were positively correlated. Correlation between moisture contents and crude ash, ether extracts, 2,6-deoxyfructosazine, 2,5-deoxyfructosazine, a value of color, citric acid, m-xylene, ${\gamma}$-butyrolactone and 5-methyl-2-furfural were negative.

• Textile Coloration and Finishing
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• v.29 no.3
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• pp.122-130
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• 2017

In the direct digital textile printing process, the pre-treatment process is an essential condition for products by forming a clear pattern by sticking and penetration of DTP dye without spreading on the fabric. Recently, pre-treatment agent is changing from high viscosity to low viscosity in order to reduce defects of fabric during pre-treatment process. In this study, pre-treatment agent of acrylic polymer with low viscosity(less than 50cps) was prepared according to the solid content of the polymer, pre-treated on the cotton fabric, and direct DTP printing was performed to compare the color and sharpness. As a result, it showed high color at a viscosity of 50cps or less. When the solid content of the polyacrylic acid having a high molecular weight(A1) was 2.5wt%, when the solid content of the polyacrylic acid having a low molecular weight(A2) was 1 - 1.5wt%, the color was the best. And when the solid content of A1 and A2 was 1.5wt%, the degree of spreading was small and A1 was superior to A2 at the sharpness.

• Journal of Ginseng Research
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• v.33 no.4
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• pp.343-348
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• 2009

This study was conducted to produce a new red ginseng by steaming ginseng using a new pre-treatment method, so as to develop ginseng products with improved flavor and thereby expand ginseng's consumer base. The color parameters (Hunter value), free sugar contents, and ginsenoside contents of the powder from the dried red ginseng, and the sensory test of the semi-dried red ginseng and the decoction from the dried red ginseng, were measured to investigate the effect of acid (ascorbic acid or citric acid) impregnation pre-treatment on red ginseng. The powder from the acid-pretreated red ginseng became lighter and more yellow than the red ginseng that was not pre-treated, but the redness (avalue) of the powder from the acid-pre-treated red ginseng increased. The ginsenoside contents of $Rg_2+Rh_1$ and $Rg_3$ increased with the acid treatment. There was a significant difference in the color and sweetness of the semi-dried acidtreated and non-treated red ginsengs in the sensory test. As the results of the sensory test were expressed in the hedonic scale, however, there were significant differences in the degrees of bitterness, astringency, sourness, odor, and color of the red ginseng decollation. Especially, the acid-treated red ginseng extract tasted less bitter, which shows the potential of new red ginseng products with improved ginseng flavor.