• Journal of Life Science
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• v.28 no.11
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• pp.1285-1289
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• 2018

Soybean [Glycine max (L.) Merr.] seed is an important dietary source of protein, oil, carbohydrates, isoflavones, and other nutrients for humans and animals. But, antinutritional factors in the raw mature soybean are exist. Kunitz trypsin inhibitor (KTI) protein and stachyose are main antinutritional factors in soybean seed. The genetic removal of the antinutritional factors will improve the nutritional value of soybean seed. The objective of this research was to breed a new yellow soybean strains (rs2rs2titi genotype) with the traits of lacking of KTI protein and low content of stachyose. Breeding population was developed from the cross of "Jinyangkong" and 15G1 parents. Presence or absence of KTI protein was detected based on Western Blot technique. Content of stachyose in mature seed was detected by HPLC. Total four new strains (603-1, 603-2, 625, and 694) with KTI protein free and low content of stachyose were selected. Four strains (603-1, 603-2, 625, and 694) have yellow seed coat and hilum. Plant height of 603-1 strain was 65 cm and 100-seed weight was 29.2 g. Plant height of 603-2 strain was 66 cm and 100-seed weight was 26.2 g. Plant height of 625 strain was 64 cm and 100-seed weight was 27.1 g. Content of stachyose for four new strains was 3.0~3.50 g/kg. Four strains selected in this research will be used to improve new yellow soybean cultivar with KTI protein free, and low content of stachyose.

• Journal of the Korea Organic Resources Recycling Association
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• v.26 no.4
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• pp.53-61
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• 2018

Anaerobic digestion (AD) is one of the most widely used process that can convert the organic fraction of waste activated sludge (WAS) into biogas. However, most researched actual methane yields of anaerobic digester (AD) on lab scale is lower than theoretical ones. Bioelectrochemical, anaerobic digester was used to increase methane yield from waste activated sludge. The influence of anaerobic digestion sludge and raw sludge mixing ratio (3:7, 5:5) on methane yield and organic matter removal efficiency were explored. As a result, when the mixing ratio of bioelectrochemical anaerobic sludge was 5:5 compared with 3:7, the highest methane yields were 294.2 mL $CH_4/L$ (0.63 times increase) and 52.5% (7.5% increase), the bioelectrochemical anaerobic digester(5:5) was more stable in the pH, t otal alkalinity and VFAs, respectively. These results showed that the increase in the mixing ratio of anaerobic digestion sludge was found to be effective for maintaining the stable performance of bioelectrochemical anaerobic digester.

• Journal of the Korean Society for information Management
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• v.38 no.1
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• pp.71-86
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• 2021

This study attempted to discover the problems related to the increasing book disposal trend within academic libraries by analyzing the disposal status over ten years and interviews with the librarians. The analysis utilized Korea Education and Research Information Service provided disposal information from 2010 to 2019. The academic libraries with more than 2 million books had disposed of the most number of books. This trend led to a distinctive decrease in the books' duplicate copies in terms of the collection composition. The librarians from the organizations, which conducted disposal more than three times and one massive removal within ten years, revealed in the interviews that they discarded many valuable duplicate books. They discussed the importance of digitizing high-value resources and also the limitation imposed by the copyright law. In conclusion, this study pointed out that book disposal can cause changes in the collection composition in the long run and suggested that academic libraries pay attention to these changes. The study also suggested evaluating the discarded books' values to guide the digitization efforts and count the number of books to include digital book use rights.

• Journal of Wetlands Research
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• v.23 no.1
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• pp.67-73
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• 2021

As the impermeable area increases due to urbanization and industrialization, the influence of non-point pollutants caused by rainfall runoff on the water system is increasing. In the past, the best management practices(BMP) were used a lot to manage non-point pollutants, but recently, technology that naturally treats them through LID (Low Impact Development) technology is widely used. In this study, various rainfall events were simulated through the SWMM model based on the data of rainfall monitoring in bioretention among natural facilities. The characteristic of LID modeling research is that it is difficult to build accurate modeling data with short-term data because real data is the result obtained through natural facilities, and it is difficult to implement an accurate model. In this study, the data monitored for 3 years It is significant in that it has built a precise model. The actual data monitored a total of 18 times was simulated, and the inflow and outflow and the removal efficiency of five pollutants were simulated. As a result of performing the performance evaluation, most of the 7 items showed excellent indicators, and the TN and TP showed relatively low simulation performance. In the future, it is expected that Korea will introduce an integrated water management system in which the water supply system and the sewage system are substantially integrated and operated. Therefore, the results of this study are considered to play an important role in the initial stage of rainfall management in the future integrated water management system, and the extent of rainfall runoff reduction and pollutant reduction in the expected installation area can be predicted in advance. This is expected to prevent overdesign of bioretention.

• Journal of Korean Society of Water and Wastewater
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• v.35 no.6
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• pp.465-476
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• 2021

Scale and rust generation in water pipes is a common phenomenon when cast iron water pipes have been used for a long time. A physical water treatment device is known among various means for suppressing rust in a water pipe, and a zinc ionization device for putting zinc metal into a pipe and emitting the zinc cation into water is one of such devices. This research measured the amount of zinc ion generated, which is known to exhibit an effect of inhibiting rust and scale generation in a pipe, and examined the scale and rust inhibition effect of the ionization device installed for ground or building water supply. In the case of distilled water, the concentration of zinc ion increased by circulating water in the ionization device several times, and it was verified to be hundreds of ㎍/L, and in the case of discharging ground or tap water, it was verified to be tens of ㎍/L. In addition, a verification pipe was installed to confirm the change inside the pipe before and after installation of the zinc ionization device, and the internal condition of the pipe was observed 3 months to several years after installation. It was confirmed that the corrosion area of the surface of the pipe was no longer increased by installing a corrosion inhibitor, and if the pipe was already filled with corrosion products, the amount of corrosion products gradually decreased every year after installation. The phenomenon of fewer corrosion products could be interpreted as expanding the space in the pipe due to the corrosion product as Fe₂O₃ adhered to the inner surface of the pipe and turned into a smaller black Fe₃O₄. In addition, we found that scale such as CaCO₃ together in the corrosion by-products gradually decreased with the attachment of the ionization device.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.22 no.5
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• pp.1-6
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• 2021

Mercury, once released, is not destroyed but accumulates and circulates in the natural environment, causing serious harm to ecosystems and human health. In the United States, sulfur-impregnated activated carbon is being considered for the removal of vapor mercury from the flue gas of coal-fired power plants, which accounts for about 32 % of the anthropogenic emissions of mercury. In this study, a high-efficiency porous mercury adsorption material was developed to reduce the mercury vapor in the exhaust gas of coal combustion facilities, and the mercury adsorption characteristics of the material were investigated. As a result of the investigation of the vapor mercury adsorption capacity at 30℃, the silica nanotube MCM-41 was only about 35 % compared to the activated carbon Darco FGD commercially used for mercury adsorption, but it increased to 133 % when impregnated with 1.5 % sulfur. In addition, the furnace fly ash recovered from the waste copper regeneration process showed an efficiency of 523 %. Furthermore, the adsorption capacity was investigated at temperatures of 30 ℃, 80 ℃, and 120 ℃, and the best adsorption performance was found to be 80 ℃. MCM-41 is a silica nanotube that can be reused many times due to its rigid structure and has additional advantages, including no possibility of fire due to the formation of hot spots, which is a concern when using activated carbon.

• Korean Chemical Engineering Research
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• v.61 no.3
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• pp.407-411
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• 2023

The urease is covalently immobilized on the surface of the magnetic particles to catalyze the conversion of urea to bicarbonate anion. The conversion was confirmed qualitatively using high-pressure liquid chromatography and UV/Vis spectrometry, and analyzed quantitatively with cyclic voltammetry. The amount of conversion with respect to time was measured and analyzed by the reaction rate equation to calculate a reaction rate constant of 0.0474 min-1. In the 1 to 3 cycles, a conversion percentage of over 90% was found, and it was possible to reuse the urease 8 times up to the percentage of 50%. It was also observed that the stability evaluated for storage for 30 days was maintained. As a result of this study, it can be seen that the urease covalently immobilized on the scaffold can be used for urea removal for the purpose of producing ultrapure water.

• The Korean Journal of Pesticide Science
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• v.17 no.4
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• pp.237-243
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• 2013

Pesticides were sprayed on perilla leaf and leafy lettuce in a greenhouse and the reduction rate of pesticide residues on each vegetable by washing were tested. The reduction rate of pesticide residues by washing for 30 sec~3 min on perilla leaf were 3~63% in tap water, 2~58% in salt water, 6~74% in green tea water, and 8~86% in detergent solution. The detergent solution only showed significant difference in reduction rates compared to the tab water washing. Considering reduction effects of the washing duration, it was showed that the reduction rates were a pattern of inclining as the duration of washing process increased, but there was no significant difference in the reduction rates except the reduction rates between washing in the detergent solution for 1 min and 3 min. Comparing washing in flowing tab water and in stagnant tab water with leafy lettuce, the reduction rate by one time washing were 8~68% in flowing tab water and 7~64% in stagnant tab water. The water and the time used in this experiment were 17.5 L, 2.9 min with flowing tab water and 4 L, 1 min with stagnant tab water. The reduction rate by 3 times washing in stagnant tab water were 16.5~76.6%, and the water and the time used were 12 L, 3 min. Therefore, when the water and the time used to wash vegetables were considered, washing two or three times in stagnant tab water could be more effective than washing one time in flowing tab water.

• Journal of Periodontal and Implant Science
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• v.29 no.3
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• pp.561-578
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• 1999

The goal of periodontal therapy is the periodontal regeneration by the removal of microorganisms and their toxic products from the periodontally diseased root surface. To achieve periodontal regeneration, root conditioning as an adjunct to root planing has been done. There are low pH etchants such as citric acid, tetracycline-HCl, and EDTA solution which is a neutral chelating agent. The purpose of present study was to examine the effect of root conditioning by citric acid, tetracycline HCl, and EDTA. Total 35 root specimens(6${\times}$3${\times}$2mm) were prepared from the periodontally diseased teeth, scaled and root planed. The specimens were treated with normal saline for 1 minute, saturated citric acid(pH 1) for 3 minutes, 50mg/ml tetracycline-HCl(pH 2) for 5 minutes, 15% EDTA(pH 7) for 5 minutes using rubbing technique. The specimens were examined under scanning electron microscopy at 1000, and 3000 magnification. On the microphotographs taken at 1000 magnification, the numbers of opened and patent dentinal tubules per unit area(10,640${\mu}m^2$) were counted. And the diameters of opened dentinal tubules per unit are (10,640${\mu}m^2$) were measured. The differences of number and diameter among all groups were statistically analyzed by Kruskal Wallis Test. The results were as follows; 1. In the specimens applied with normal saline(control group), the root surface was finely cracked, and was covered by irregular smear layer. Neither exposed dentinal tubules nor any patent dentinal tubules could be seen. 2. In the specimens applied with saturated citric acid(experimental 1 group), the globular collagen fibers were exposed around the peritubular space, and many dentinal tubules were revealed. 3. In the specimens applied with tetracycline-HCl(experimental 2 group), the process-like collagen fibers were exposed around the peritubular space, and some dentinal tubules were revealed. 4. In the specimens applied with 15% EDTA(experimental 3 group), the root surface was covered by the collagenous fibrillar network, and many dentinal tubules were revealed. 5. The numbers of opened and patent dentinal tubules were significantly more in exp. 1 group and exp. 3 group than in exp. 2 group(P<0.05). But there was no significant difference between exp. 1 group and exp. 3 group. In control group, the number of opened and patent dentinal tubules could not be counted because any dentinal tubules couldn't be seen. 6 . The diameter of opened dentinal tubules was significantly smaller in exp. 1 group and exp. 3 group than in exp. 2 group(P<0.05). But there was no significant difference between exp. 1 group and exp. 3 group. In control group, the diameter of opened dentinal tubules could not be measured because any dentinal tubules couldn't be seen. The results demonstrate that root conditioning with citric acid, tetracycline- HCl, and EDTA is more effective in periodontal healing than only root planing, and 15% EDTA solution can replace low pH etching agents such as citric acid, tetracycline-HCl for root conditioning.

• Progress in Medical Physics
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• v.5 no.2
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• pp.57-68
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• 1994

Purpose : The purposes are to discuss the reason to measure dose distributions of circular small fields for stereotactic radiosurgery based on medical linear accelerator, finding of beam axis, and considering points on dosimetry using home-made small water phantom, and to report dosimetric results of 10MV X-ray of Clinac-18, like as TMR, OAR and field size factor required for treatment planning. Method and material : Dose-response linearity and dose-rate dependence of a p-type silicon (Si) diode, of which size and sensitivity are proper for small field dosimetry, are determined by means of measurement. Two water tanks being same in shape and size, with internal dimension, 30${\times}$30${\times}$30cm$^3$ were home-made with acrylic plates and connected by a hose. One of them a used as a water phantom and the other as a device to control depth of the Si detector in the phantom. Two orthogonal dose profiles at a specified depth were used to determine beam axis. TMR's of 4 circular cones, 10, 20, 30 and 40mm at 100cm SAD were measured, and OAR's of them were measured at 4 depths, d$\sub$max/, 6, 10, 15cm at 100cm SCD. Field size factor (FSF) defined by the ratio of D$\sub$max/ of a given cone at SAD to MU were also measured. Result : The dose-response linearity of the Si detector was almost perfect. Its sensitivity decreased with increasing dose rate but stable for high dose rate like as 100MU/min and higher even though dose out of field could be a little bit overestimated because of low dose rate. Method determining beam axis by two orthogonal profiles was simple and gave 0.05mm accuracy. Adjustment of depth of the detector in a water phantom by insertion and remove of some acryl pates under an auxiliary water tank was also simple and accurate. TMR, OAR and FSF measured by Si detector were sufficiently accurate for application to treatment planning of linac-based stereotactic radiosurgery. OAR in field was nearly independent of depth. Conclusion : The Si detector was appropriate for dosimetry of small circular fields for linac-based stereotactic radiosurgery. The beam axis could be determined by two orthogonal dose profiles. The adjustment of depth of the detector in water was possible by addition or removal of some acryl plates under the auxiliary water tank and simple. TMR, OAR and FSF were accurate enough to apply to stereotactic radiosurgery planning. OAR data at one depth are sufficient for radiosurgery planning.