• Journal of Biosystems Engineering
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• v.32 no.6
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• pp.455-461
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• 2007

The electric current of a flow injection type enzyme-sensor was measured to confirm the stable operating conditions of the sensor. The current of the sensor was decreased as the buffer solution velocity increased. Under the limitation of the cycle time to be below 10 minutes, the effective ranges of the buffer solution velocity were suggested $0.10{\sim}0.26$, $0.12{\sim}0.24$, $0.1{\sim}0.25$ and $0.05{\sim}0.10\;cm/s$ of 1.0, 1.4, 2.4 and 3.4 mm of the electrode diameters, respectively. As the reaction time of the enzyme and the substrate was increased, the current was decreased because of the dilution between the sample and buffer solution. Therefore, it could be recommended that the reaction time was able to be selected as shortly as possible in consideration of the total cycle time. As the result of the experiments using a different volume ratio of the enzyme to substrate, it was concluded that the substrate had to be mixed with the same amount of the enzyme. The current have increased remarkably in proportion to the electrode diameter under 0.1 cm/s of the buffer solution velocity but there was no difference over 0.1 cm/s of the buffer solution velocity. The cross type arrangement of the electrode was highly suggested for application and machining of the sensor.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.43 no.1
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• pp.1-5
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• 1998

Experiments were carried out to find out the optimum water potential, temperature, and duration for the priming of rice seeds, Oryza sativa L. (cv. Ilpumbyeo) for better germination at sub-optimal temperatures. Seeds were primed in 0, -0.2, -0.4, -0.6, -0.8, and -1.0 MPa PEG (polyethylene glycol) solutions at $25^{\circ}C$. The optimum water potential for seed priming, the highest water potential at which rice seeds did not germinate, was -0.6 MPa. To find out optimum priming temperature and duration rice seeds were primed in -0.6 MPa PEG solution and 0 MPa (water as a control) for various durations at 15 and $25^{\circ}C$ and the seeds were germinated at 17, 20, and $25^{\circ}C$. Considering germination rate and speed, the optimum priming time in water (0 MPa) was 4 days at 15$^{\circ}C$ and 1 day at $25^{\circ}C$, while 4 days was the optimum priming time in a -0.6 MPa PEG solution, regardless of the priming temperature. Priming reduced the actual time of germination, especially at sub-optimal temperatures. Priming did not affect germination rate in -0.6 MPa PEG solution at 15$^{\circ}C$, but overpriming reduced the final germination rate in water at 15$^{\circ}C$ and in -0.6 PEG solution at $25^{\circ}C$. Total sugars and $\alpha$-amylase activity induced during the seed priming were negatively correlated with the final germination rate and there was no noted relationship with the speed or uniformity of germination.

• Journal of Surface Science and Engineering
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• v.49 no.5
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• pp.454-460
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• 2016

Double-layered Al-Mg films have been deposited by using an e-beam deposition method on a cold-rolled steel sheet(CR), which the structure of the film was Al/Mg/CR. The micro-structure, alloy phase, and corrosion resistance of the Al-Mg coated CR were investigated before and after heat treatment at $400^{\circ}C$ for 2, 3, and 10 min in a nitrogen atmosphere. Total thickness of Al-Mg films was fixed at $3{\mu}m$ and the thickness ratio of Al and Mg layers(Al:Mg) has been changed from 5:1 to 1:5. The cross-sectional morphology of the films, which had the thickness ratio of 2:1(Al:Mg), 1:1, and 1:2, was changed after heat treatment from columnar to featureless structure. The x-ray diffraction data for as-deposited films showed only pure Al and Mg peaks. Al-Mg alloy peaks such as $Al_3Mg_2$ and $Al_{12}Mg_{17}$ phase appeared after the heat treatment. The Al-Mg coating with the thickness ratio of 1:1(Al:Mg) showed the best corrosion resistance of up to 500 hours by salt spray test.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.35 no.3
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• pp.146-152
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• 2009

Traditional surgical method or injection using filler is performed for soft tissue augmentation. Surgical methods have disadvantage of surgical morbidity. Commercially available injectable materials have the disadvantages such as resorption, short-term effect. repeated application and hypersensitivity. Significant shortcoming of cell therapy using autologous fibroblasts is delay of treatment effect. Chitosan/${\beta}$-glycerol phosphate (GP) solution has thermosensitive property and allows sol-gel transition at physiologic pH and temperature. These properties may resolve the delay of treatment effect. The purposes of this study are to evaluate the viscosity and pH changes of chitosan/${\beta}$-GP solutions and to evaluate the effect of chitosan/${\beta}$-GP solution on fibroblast proliferation and production of collagen. We measured the viscosity and pH as function of temperature, of the solution containing 1:0.7, 1:0.75, 1:0.8 chitosan (1, 10, 100, 700 kDa) /${\beta}$-GP. Fibroblasts from ears of 5 rats were cultured in chitosan/${\beta}$-GP solutions for 3 weeks. Cell proliferation and collagen contents were measured every week with WST (water-soluble tetrazolium salt) assay and Collagen assay respectively. The Results are 1) Chitosan(100 kDa<)/${\beta}$-GP solution (1:0.75) showed sol-gel transition at physiologic pH and body temperature and injectable properties. It will enable to resolve the delay in treatment effect 2) Cell proliferation and total collagen contents of the control group were increased with time. However, these decreased after the 1st week in experimental group 3) Collagen contents in the experimental group are higher than that of control group. Chitosan/${\beta}$-GP solution may provide favorable conditions for cell function

• Journal of the Korean Chemical Society
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• v.16 no.2
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• pp.80-83
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• 1972

The activity change of lysozyme resulted from its exposure to $Ti-H_2O_2$system in aqueous liquid at room temperature and to ${\gamma}$-irradiation in ice at $195^{\circ}K$ has been measured at room temperature with a Cary-14 spectrophotometer. The enzymatic activity of lysozyme which had been added to a previously flow-mixed solution of $TiCl_3$ and $H_2O_2$ (System I) was compared with the activity of a lysozyme-$H_2O_2$ solution after flow-mixing with $TiCl_3$ (System II), considering the differences between these two activity changes as the extent of the enzymatic inactivation by the involvement of OH radical reaction. The fraction of lysozyme inactivated by OH radical in the system containing 0.0025 M $TiCl_3-0.1M$ $H_2O_2$ (ph 3.5) was 13%, When the $TiCl_3$ concentration is double (pH 3.0), the fraction of enzyme inactivated increases to 36%. The activity of the system containing 0.025 M $TiCl_3-0.1$ M $H_2O_2$ (pH 1.5) was essentially zero. The results seem to support the previos view that the production of OH radical should be proportional to $TiCl_3$ concentration when $H_2O_2$ is present in excess. Increase in the extent of inactivation found in system I with increasing $TiCl_3$ concentration may be due to a pH effect. $H_2O_2$ seems to be less effective than $TiCl_3$ in the inactivation. 1% lysozyme solution, when ${\gamma}$-irradiated with a total dose of 3M rads, loses about 20% of its activity. Lowering of temperature also was found to yield a reduction in enzymatic activity.

• Korean journal of food and cookery science
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• v.30 no.3
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• pp.351-359
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• 2014

The application of persimmon for making new products was investigated by analyzing the degree of astringency removal, softness of fruit, and sensory properties of Daebong persimmons (Diospyros kaki L) treated with three different astringency removal methods of steeping in water, steeping in 1% salt solution, and vacuum packing at $40^{\circ}C$. The weight of persimmon fruit increased with increasing steeping time, but decreased with increasing vacuum packing time. The fruit steeped in $40^{\circ}C$ salt solution (1%, w/w) was not detected with soluble tannin and not developed color with ferric chloride after steeping for 9 h. A total of 12 h of steeping time was required for removing soluble tannin using other methods. The lightness (L) in color and hardness in texture decreased when storage time increased, regardless of astringency removal methods. In overall, the preference was shown with the highest score in persimmon steeped in salt solution for 9 h and 12 h that were vacuum packed at $40^{\circ}C$. In conclusion, the astringency removal condition of Daebong persimmon was good after being steeped on 1% salt solution for 9 h at $40^{\circ}C$.

• Journal of Soil and Groundwater Environment
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• v.18 no.6
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• pp.38-47
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• 2013

This study was performed to identify the optimal operating conditions and to evaluate the xylene removal efficiency, applying in-situ soil flushing with the low concentrated solution of 'Tween 80' at the xylene contaminated site. The pilot scale test site ($5m{\times}5m{\times}3m$), was mainly composed of 'sandy loam', with the average hydraulic conductivity of $9.1{\times}10^{-4}cm\;s^{-1}$. The average xylene concentration of the site was 42.1 mg $kg^{-1}$, which was more than 2.5 times higher than Korea soil pollution warning limit (15 mg $kg^{-1}$). For the soil flushing, 7,800 L of 0.1~0.2% surfactant solution was injected into three injection wells at the average injection time of 9 hr $d^{-1}$ for 10 days, followed by the additional only groundwater injection of 6,000 L. The same amount of the effluent solution was extracted from three extraction wells. From the analysis for xylene concentration of all effluent at 3 extraction wells, total 166 g of xylene was removed by in-situ surfactant flushing. Even though the residual xylene concentrations of 7 soil sampling locations in the test site were different due to the soil heterogeneity, from the comparison of xylene concentration at 7 locations before/after the feasibility test, 53.9% of the initial xylene in the site was removed from three extraction wells (mainly Ext-N and Ext-M well). The results showed that the in-situ soil flushing by using low concentrated 'Tween 80' solution had a great potential to remediate the xylene contaminated site.

• Journal of Chest Surgery
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• v.25 no.5
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• pp.469-479
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• 1992

Searching for the clinical effects of colloid solutions that used to increasing the oncotic pressure of priming solutions at the cardiopulmonary bypass, 29 patients [who were diagnosised as simple VSD around 10kg of body weight and scheduled to be operated from June 1990 to December 1990 at Sejong General Hospital] were divided randomly and prospectively to the two groups: A group [15] was received 4gm% albumin as addition to the priming solutions and B Group [14] the same amount of Ringer`s lactated solution. 34 clinical parameters [Body weight, sex, age, body surface area, Qp/Qs, pulmonary arterial pressure, cardiopulmonary bypass time, anesthetic time, intraoperatively infused crystalloid and colloid amount, hemoglobin, hematocrit, serum sodium concentration, serum osmolarity, urine osmolarity, urine specific gravity, serum concentration, serum osmolarity, urine osmolarity, urine specific gravity, serum protein, serum albumin concentration, urine output, central venous pressure, postoperatively infused colloid amount, immedediate post-operative peak inspiratory pressure, cardiac index, blood pressure and pump flow during cardiopulmonary bypass, inotro-pic assist, diuretics, extubation period, total drain amount, duration of ICU] were measured and compaired between the two groups. There were no differences of preoperative and operative clinical parameters. And postoper-atively, practically there were no nearly differences at the clinical outcomes between the two groups, but some parameters [cardiac index, PIP, BP and pumpflow during CPB, etc] contributed to being preferable to the Group A at certain times [P<0.05]. Conclusively, it might be thought that the priming solution of cardiopulmonary bypass added by colloid solution had some beneficial effects on the patients, especially younger and associated with complex anomaly to be expected taken longer time of cardiopulmonary bypass, and more studies about the neonatal and complex anomaly cases were needed in that points.

• Journal of Chest Surgery
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• v.2 no.2
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• pp.147-154
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• 1969

This is a report on a total of 11 cases of esophageal perforation in the department of thoracic surgery, Chonnam University Hospital during the period of 8 years from 1962 to 1969. They occurred by the following agents, that is,lye solution[7 cases], fish bone[2 cases]. compress air [one case], strong acid [one case]. The perforated portions of esophagus were cervical esophagus in 2 cases, upper third of esophagus in 5 cases, middle third of esophagus in 3 cases and lower third of esophagus [abdominal esophagus] in one case. 4 cases out of cases of esophageal perforation after ingestion of Lye solution were due to Bougination to improve esophageal stenosis: 2 cases occurred 2 months after ingestion of Lye solution and the remaining 2 cases, 2 to 3 weeks after Lye solution ingestion. Therefore, It is realized that Bougination for esephageal stricture by Lye solution is particularly dangerous. The complication after esophageal perforation were mediastinitis,[10 cases], right pyothorax with mediastinitis [8 cases], peritonitis [4 cases], esophago-bronchial fistula[one case]. Owing to the various complications above mentioned, surgical approach to esophageal perforation is accordingly complicated and a combination of more than two of the following different procedures were properly used case by case, that is. gastrostomy or jejunostomy for feeding and esophageal rest,thoracotomy and chest drainage, lung decortication for pyothorax, primary closure of compress air perforation and esophago-bronchial fistula, mediastinostomy, retrosternal esophagoplasty using right colon to Lye stricture etc. 5 cases[45. 5%] of 11 cases were expired and the rest of 6 cases[54.5%]were survived with complete accomplishment of surgical procedures and satisfactory healing in 4 cases and interruption of follow up in 2 cases because of poor economical condition of the patients.

• Food Science and Preservation
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• v.11 no.1
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• pp.17-21
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• 2004

The antimicrobial effect of mixed solution of botanical antimicrobial agent-citrus product (BAAC) and such a natural additive as aloe, ginseng or Prunus mume extract on the spoilage microorganisms of soybean sprouts were investigated by paper disk method. The mixture (BAAG) of BAAC and ginseng extract showed the remarkable antimicrobial activity in the result of the experiment. Therefore, we used BAAG as pre-soaking and cultivating solution of soybean sprouts. Total bacterial and Escherichia coli cell count of soybean sprouts pre-soaked and cultivated in the BAAG-diluted solution (50 ppm) showed 2.5 ${\times}$ 10 CFU/mL and 1.3 ${\times}$ 10 cfu/mL in comparison with 3.5 ${\times}$ 10$^3$ cfu/mL and 5.8 ${\times}$ 10$^3$ cfu/mL of the control, respectively. BAAG-treated soybean sprouts also showed no slimy brown product and undesirable odor characterized in the control. It was confirmed that BAAG could be a proper pre-soaking and cultivating solution of soybean sprouts.