• Journal of the Korean Society of Food Culture
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• v.8 no.3
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• pp.267-274
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• 1993

This study was aimed to investigate the changes in textural properties of Korean radish and relevant chemical, enzymatic activities during salting. During salting, pH was decreased and total acidity was increased. The maximum compression and puncture forces of Korean radish were decreased significantly whereas cutting force was increased. From the force-distance curves, the break point and maximum force point disappeared in salted Korean radish whereas these appeared apparently in fresh one. Also, the number of peak obtained by three types of test from salted Korean radish was decreased. Hot water soluble pectin and 0.4% Na-hexametaphosphate soluble pectin were increased whereas 0.05 N-HCl soluble pectin were decreased significantly. Polygalacturonase activity were increased in Korean radish solid(RS) and Korean radish juice(RJ) until 4 days of salting. Pectin esterase activity were decreased in RS and RJ. Cx-cellulase activity did not appear initially, however, they began to show their activities after 2 days of salting and were increased in RJ although it was low.

• Journal of the Korea Organic Resources Recycling Association
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• v.28 no.3
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• pp.15-26
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• 2020

To recover phosphorus from incinerated sewage sludge ash(ISSA), ISSA were extracted with sulfuric acid solution, and the optimal phosphorus recovery conditions were experimented by comparing the recovered phosphorus contents and heavy metals by raising pH. Also the phosphorus recovery efficiency was compared when acid extract was reused or classified by particle size of ISSA. The optimal conditions for recovering phosphorus from ISSA were 1N sulfuric acid solution with an L/S ratio of 10, and an extraction time of 30 minutes. Considering the addition of alkali substances and the content of heavy metals in the recovered sediment, it is concluded to recover phosphorus under pH 5. Reuse of the ISSA extract increased the recovery rate of phosphorus by 14~21% depending on the reuse rate (100 and 50%), but it also increased zinc contents to 33 and 21%, and copper contents to 35 and 20%, respectively. The experiment of ISSA divided into four sections by particle size showed that there was no distinct advantage of phosphorous recovery by classification of certain particle size of ISSA. The removal of heavy metals from extracts through EDTA and cation exchange resin showed no definite effect.

• Analytical Science and Technology
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• v.13 no.3
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• pp.309-314
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• 2000

The quantitative analysis of various trace metals including fission products in lithium molten salts has been performed using a inductively coupled plasma atomic emission spectrometer (ICP-AES). The spectral interferences of lithium content, 500, 1,000 and 2,000 mg/L, in the sample solution were investigated using an optimum wavelength for the respective metal species. As a result, the line intensities for Y, Nd, Sr, and La had no influences from the lithium content up to 2,000 mg/L, while Mo, Ba, Ru, Pd, Rh, Zr and Ce showed spectral interferences of 10% to 50%. The group separation of metals from lithium in the molten salts solution was carried out by adding ammonia water into the solution. The recovery of Ru, Y, Rh, Zr, Nd, Ce, La and Eu was found to be over 90%, while Mo, Ba, Pd, and Sr provided low recovery percentages.

• Journal of the Korean Society of Food Science and Nutrition
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• v.43 no.5
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• pp.735-740
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• 2014

The study investigated the roast color formation properties of ginseng upon soaking in threonine/sucrose solution followed by roasting. To determine operational parameters, including threonine concentration ($X_1$, 0.1~0.9%), sucrose concentration ($X_2$, 1.0~3.0%), and roasting temperature ($X_3$, $130{\sim}170^{\circ}C$), response surface methodology was applied to monitor color properties, including brown color intensity, Hunter's colors, and organoleptic color. Coefficients of determinations ($R^2$) of the models were above 0.8758 (P<0.05) in terms of brown color intensity and Hunter's color parameters. Brown color intensity of roasted ginseng extract was maximized in 0.70% threonine and 2.32% sucrose soaking solution under roasting conditions of 25 min at $166.03^{\circ}C$. a values of roasted ginseng were maximized in 0.74% threonine and 2.19% sucrose soaking solution under roasting conditions of $165.40^{\circ}C$. b values of roasted ginseng were maximized in 0.61% threonine and 2.28% sucrose soaking solution under roasting conditions of $159.16^{\circ}C$. The maximum organoleptic color score of roasted ginseng extract was 7.27 in 0.53% threonine and 1.01% sucrose soaking solution under roasting conditions of $146.96^{\circ}C$.

• Journal of the Microelectronics and Packaging Society
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• v.23 no.3
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• pp.51-56
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• 2016

To fabricate a copper (Cu)-based fine conductive filler having antioxidation property, submicron silver (Ag)-coated Cu particles were fabricated and their antioxidation property was evaluated. After synthesizing the Cu particles of $0.705{\mu}m$ in average diameter by a wet-reduction process, Ag-coated Cu particles were fabricated by successive Ag plating using ethylene grycol solvent. Main process parameters in the Ag plating were the concentration of reductant (ascorbic acid), the injection rate of Ag precursor solution, and the stirring rate in mixed solution. Thus, Ag plating characteristics and the formation of separate fine pure Ag phase were observed with different combinations of process parameters. As a result, formation of the separate pure Ag phase and aggregation between Ag-coated Cu particles could be suppressed by optimization of the process parameters. The Ag-coated Cu particles which were fabricated using optimal conditions showed slight aggregation, but excellent antioxidation property. For example, the particles indicated the weight gain not exceeding 0.1% until $225^{\circ}C$ when they were heated in air at the rate of $10^{\circ}C/min$ and no weight gain until 75 min when they were heated in air at $150^{\circ}C$.

• Clean Technology
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• v.16 no.2
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• pp.117-123
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• 2010

In this study, we propose two methods able to recover different type of gold from gold-cyanide solutions: biosorption and desorption process for mono-valent gold recovery and biosorption and incineration process for zero-valent gold recovery. The waste bacterial biomass of Corynebacterium glutamicum generated from amino acid fermentation industry was used as a biosorbent. The pH edge experiments indicated that the optimal pH range was pH 2 - 3. From isothermal experiment and its fitting with Langmuir equation, the maximum uptake capacity of Au(I) at pH 2.5 were determined to be 35.15 mg/g. Kinetic tests evidenced that the process is very fast so that biosorption equilibrium was completed within the 60 min. To recover Au(I), the gold ions were able to be successfully eluted from the Au-loaded biosorbent by changing the pH to pH 7 and the desorption efficiency was 91%. This indicates that the combined process of biosorption and desorption would be effective for the recovery of Au(I). In order to recover zero-valent gold, the Au-loaded biosorbents were incinerated. The content of zero-valent gold in the incineration ash was as high as 85%. Therefore, we claim on the basis of the results that two suggested combined processes could be useful to recover gold from cyanide solutions and chosen according to the type of gold to be recovered.

• Current Research on Agriculture and Life Sciences
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• v.6
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• pp.13-18
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• 1988

This experiment was conducted to identify the enzyme treatment time, calcium ion effect, enzyme concentration and leaf position for protoplast isolation. It was also performed to determine the adequate molarity on protoplasts, and to investigate the incubation time, pH, PEG concentration and DMSO effect for protoplast fusion. The results obtained were summarized as follows ; The optimal time of incubation in enzyme solution was 4 hours. And the protoplast releasing time was delayed by $CaCl_2{\cdot}2H_2O$ addition to the enzyme solution compared with no added one. The viability had kept up to above 95% until the 4 hours after digestion. The high viability of the protoplast was preserved more than 16 hours by adding $CaCl_2{\cdot}2H_2O$ to digestion solution. The enzyme concentration had no effect on protoplast yield in range from 1% to 5% and the first or second leaf from the top of the plant produced the highest protoplast yield among the leaf position tested. The purity of healthy protoplast was better in 0.4M and 0.5M sucrose than in others, and the percentage of protoplast aggregation was more 20% to 50% in PEG 6,000 compared with 4,000 and PEG 1,500. Even though the percentage of protoplast aggregation was less increased by 3% to 7% than without DMSO, its treatment was effective to induce binucleated protoplasts.

• Weed & Turfgrass Science
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• v.2 no.2
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• pp.176-183
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• 2013

To explore hydrolysis methods for the efficient manufacture of sugar solutions from the freshwater alga Water-net (Hydrodictyon reticulatum, HR), acid hydrolysis, enzymatic hydrolysis, and combined hydrolysis (acid followed by enzymatic hydrolysis) were investigated. In the one-step acid hydrolysis, the reaction of 8% solids content using 2% sulfuric acid at $120^{\circ}C$ for 1 hour was desirable. In this case, glucose 27.44 g 100 g $DM^{-1}$ could be obtained from the HR-d13 samples. In the two-step acid hydrolysis, the primary hydrolysis (HR powder : 72% sulfuric acid = 1 g : 1.5 mL) was carried out for 1 hour at $60^{\circ}C$, and then the secondary hydrolysis was done for 1 hour at $120^{\circ}C$ after addition of distilled water 23.5 mL. In this case, glucose 35.11 g/100 g DM could be obtained from the HR-d13 samples. In the combined hydrolysis, 25% solids content using 2% hydrochloric acid were reacted for 1 hour at $120^{\circ}C$, and then citrate buffer and hydrolysis enzyme complexes (E1 1.0 mL+E2 0.2 mL $g^{-1}$ dried matter) were added and reacted for 1 - 2 days at $50^{\circ}C$. In this case, glucose 33.5 g 100 g $DM^{-1}$ could be obtained from the HR-d23+26 samples. In conclusion, combined hydrolysis was likely to be more useful saccharification method of HR biomass at a practical level, considering the glucose productivity, generation of fermentation-inhibiting substances (hydroxyl methyl furfural, furfural), and limited use of strong acid.

• Korean Journal of Animal Reproduction
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• v.21 no.2
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• pp.131-137
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• 1997

This study was carried out to investigate the in vivo development rates of vitrified-thawed mouse expanding, hatching and hatched blastoc ysts(BL). In vitro fertilization produced blastocysts were vitrified in EFS40(40% ethylene glycol, 30% Ficoll and 0.3 M sucrose in phosphate buffer saline containing 10% FBS). Expanding a and hatching blastocysts were equilibrated in 20% ethylene glyco](EG) for 5 min. before exposure to EFS40 at 25°C for 1 min., they were then vitrified in liquid nitrogen. Hatched blastocysts which cultured in m-CR1 medium supple mented 0.4% bovine serum albumin on day 5. were equilibrated in 10% EG for 5 min. and then vitrified in EFS40 for 30 sec. After thawing, re-expanding blastocysts were transferred to recipients(3 day of pseudopregnant) on one or both uterine horns(6-8 embryos per a horn). Preg¬n nancy rates of recipients and implantation were a assccessed by autopsy on 15 gestation. The res¬u ults obtained in these experiments were summar¬1 ized as follows; 1) The pregnancy and live fetus rates, for vitrified expanding BL(77.8 and 25.0%) and hatching BL(77.8 and 26.4%)n vitro were not significantly difference in those of control BL (66.7 and 42.9%: 83.3 and 40.4%), respectively, 2) in vitro development of vitrified hatched BL was 34.0%. and 3) in vivo developmental rate of vitrified hatched BL was only 33.3%. These results suggested that proposed rapid vitrification p procedures used EFS40 cryoprotectant can be effectively performed in mouse expanding Ihatching blastocysts and that mouse blastocysts a after being hatched from zona pellucida can be successfully cryopreserved.

• Applied Biological Chemistry
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• v.39 no.5
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• pp.361-367
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• 1996

As a part of investigation for quality improvement of surimi gel from fish with a red muscle by addition of emulsion curd, we investigated the processing conditions of emulsion curd contained succinylated gelatin from conger eel skin as an emulsifier and emulsion curd-added surimi gel. Activity and stability of emulsion curd on standing at room temperature, chilled temperature and vibration were remarkably improved by the addition of 15 tunes of soybean oil and 5 times of water to succinylated gelatin from conger eel skin. The proximate composition of the emulsion curd was moisture 18%, protein 5%, lipid 76% and ash 0.5% and its appearance was white. Peroxide value and fatty acid composition of emulsion curd contained succinylated gelatin as an emulsifier were similar to these of soybean oil. By the addition of 6% of emulsion curd to mackerel surimi, gel strength, appearance and texture of the resulting surimi gel were improved, while its peroxide value and brown pigment revealed minor change. From the results of volatile basic nitrogen, viable cell counts and histamine content, the emulsion curd-added mackerel surimi gel can be safe In the sense of food sanitation.