• Bulletin of the Korean Chemical Society
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• v.21 no.9
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• pp.855-859
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• 2000

An application of synergistic solvent extraction for the etermination of trace lithium in sea water has been studied by forming an adduct complex of thenoyltrifluoroacetone (TTA) and trioctylphosphine oxide (TOPO) in a solvent. The interference by major constituents in sea water was eliminated by phosphate precipitation. Ex-perimental conditions such as solution pH, concentrations of TTA and TOPO etc. were optimized in synthetic sea water with similar compositionto its natural counterpart. To eliminate the interference, 1.38g of ammoni-um dihydrogen phosphate and 2.5 mL of ammonia water were added into 100 mL of thediluted solution at $60^{\circ}C$ to form the phosphate precipitates of Ca2+ and Mg2+ ions. After the pH of this filtrate was adjusted to 8.0, 10.0 mL of m-xylene containing 0.1 M TTA and 0.05 M TOPO was added to the solution in a separatory funnel, and the solution was shaken vigorously for 20 minutes. The solvent was separated from the aqueous solution, and 20 uL of m-xylene solution was injected into a gaphite tube to measure the absorbance by GF-AAS. The detection limit was 0.42 ng/mL. Lithium was determined within the range of 146 to 221 ng/mLin Korean coast-al sea waters, and the recoveries in the spiked samples were 94 to 106%.

• Nuclear Engineering and Technology
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• v.37 no.4
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• pp.317-326
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• 2005

The burning-out of excess plutonium from the reprocessing of spent nuclear fuel and from the dismantlement of nuclear weapons is recently emphasized due to the difficulties in securing the final repository for the spent fuel and the necessity to consume the ex-weapons plutonium. An irradiation test in the Halden reactor was launched by the OECD Halden Reactor Project (HRP) to investigate the in-pile behavior of plutonium-embedded fuel as a form of mixed oxide (MOX) and of inert matrix fuel (IMF). The first cycle of irradiation was successfully accomplished with good integrity of test fuel rods and without any undesirable fault of instrumentations. The test results revealed that the MOX fuel is more stable under irradiation environments than IMF. In addition, MOX fuel shows lower thermal resistance due to its better thermal conductivity than IMF. The on-line measured in-pile performance data of attrition milled MOX fuel are used in the analysis of the in-pile performance of the fuel with the fuel performance code, COSMOS. The COSMOS code has been developed for the analysis of MOX fuel as well as $UO_2$ fuel up to high burnup and showed good capability to analyze the in-reactor behavior of MOX fuel even with different instrumentation.

• YAKHAK HOEJI
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• v.36 no.4
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• pp.370-378
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• 1992

A simple and sensitive high performance liquid chromatographic method to quantitate ${\alpha}-keto$ acids in serum and urine was investigated. ${\alpha}-Keto$ acids react with 1,2-diamino-4,5-methylenedioxybenzene (DMB) in the presence of 2-mercapto-ethanol and sodium hydrogen sulfite to form highly fluorescent derivatives, substituted 6,7-methylenedioxyquinoxalinol. The derivatization procedure was performed in water bath at $100^{\circ}C$, and completed within 50 min. By the use of a reversed-phase column and multi-step gradient with two solvents, a mixture containing twelve of these derivatives were efficiently resolved within 35 minutes. The optimal wavelengh of the fluorescence detector are ${\lambda}_{ex}=364\;nm$ and ${\lambda}_{em}=445\;nm$. The quantitation of the individual ${\alpha}-Keto$ acids was reproducible with relative standard deviation of $3.0{\sim}7.9%$ and had a detection limits of $10{\sim}60$ fmol, except for p-hydroxyphenylpyruvic acid (960 fmol).

• Journal of Arbitration Studies
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• v.30 no.4
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• pp.95-119
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• 2020

Securing a stable supply chain is becoming a significant concern among countries as the global uncertainty rises with the expansion of global protectionism and the result of what the COVID-19 pandemic has brought around the world. This study has investigated dispute cases between customs authority and trade corporations based on the KOREA-ASEAN FTA and suggested the following implications and improvements: Firstly, the extent (varieties) of the proof document on cumulation and its form should be stipulated and provided through consultation between customs from each contracting party. Secondly, it ought to be prescribed as an obligation so that producers located in the third country can cooperate in providing documents for certification of origin. The duty to provide such documentary evidence should also be specified when making EX-IM contracts. Lastly, origin verification provisions regarding cases to which cumulation is applied have to be complemented so that the verification period's extension can be applied and approved. One can expect that the abovementioned responses on cumulation will enhance the availability of KOREA-ASEAN FTA.

• Journal of the korean academy of Pediatric Dentistry
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• v.38 no.2
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• pp.146-154
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• 2011

An in vitro study on cariogenic potential of 8 over-the-counter syrups for children was performed. The experimental groups were 8 over-the-counter syrups. The positive control group was 10% sucrose solution, and the negative control group was artificial saliva. The pH of each group was determined. The buffering capacity was measured by the volume of 2 N NaOH adding to equalize the pH of 20 ml of experimental solution to pH 7. The consistency was measured by the time to pass Ostwald pipette for 2 ml of the experimental solution. The experimental solutions were inoculated with S. mutans and cultured in $37^{\circ}C$ anaerobic condition for 48 hours. To estimate acid production, pH of the experimental solutions were measured before and after the culture. The primary teeth specimens were soaked in the experimental solutions for 20 minutes three times a day. Except on those hours the specimens were stored in artificial saliva. After 5 days, the microhardness changes of the specimens were measured. These results show that most of syrup-form medicines for children tend to have cariogenic potential partially in endogenous pH, buffering capacity, consistency, acid production and erosive ability of enamel. For the oral health of children, the alternative sweeteners (ex. xylitol) may be substituted for the cariogenic sweeteners of syrups. Additionally, It may be helpful that the chewable tablet replace liquid or syrup in term of dose form.

• Korean Journal of Agricultural Science
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• v.45 no.2
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• pp.197-203
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• 2018

Biochar is the carbon solid produced through the pyrolysis of a biomass from organic sources such as agricultural waste, animal manure, and sludge under limited or anaerobic conditions. Biochar has the effect of reducing greenhouse gases through the carbon sequestration method; additionally, biochar is known to function as a soil amendment. This experiment was conducted to evaluate the application of biochar on the growth characteristics of Chinese cabbage at Chungnam National University in Daejeon, Korea. The Chinese cabbage was grown for 50 days in a glasshouse in pots. A pruning branch was used to produce the bead and pellet forms of biochar through pyrolysis. The biochar was added to the soil at 0, 2, and 5% by weight. The Chinese cabbage with the 2% treatment of the bead form of biochar had the highest fresh weight ($149.43{\pm}15.92g\;plant^{-1}$) which was increased by 10% compared to the control ($136.91{\pm}31.46g\;plant^{-1}$). Moreover, for the 5% treatment of the bead form of biochar ($60.91{\pm}9.82g\;plant^{-1}$), the growth decreased by 57% compared to the control. As the content of the bead form of biochar increased, the shoot dry weight, leaf number, leaf length and lead width that appeared decreased. An increase in the total organic matter, Avail. $P_2O_5$, Ex. cation and EC was observed when the biochar content was increased. Our results support the application of 2% biochar in the bead form for increased growth of Chinese cabbage.

• Korean Security Journal
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• no.50
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• pp.91-115
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• 2017

Recently the characteristics of those who committed serious terrorist crimes are not directly related to the direct command system of a specific terrorist organization (ex. IS) but are influenced by the political propaganda of terrorist organizations online, Terrorist crime under the loose form of the terrorist organization. Therefore, this study suggests ways to improve countermeasures against terrorism in metropolitan subways. Although it is important for the prevention of terrorism in the subway, it is important for the police officers of the subway police and the special police officers of the railway to have a physical limit to take charge of them, and after confirming that improvement measures are necessary, And pointed out the possibility of establishing independent security departments where judicial and administrative control is not feasible to grant police rights. In addition, I pointed out how to improve the safety of subways in the metropolitan area through the recruitment of core job candidates and the identity survey during the subway operation. Furthermore, it was confirmed that a special council on terrorism, which can take into consideration the characteristics of subway terrorism, such as airports and ports, is required to be established in charge of terrorism prevention under the current Anti-Terrorism Act. Finally, it is once again emphasized that the strengthening of the powers of the counterparts to terrorism must inevitably limit the basic rights of the people, so the principle of proportionality must be observed in their activities.

• Korean Journal of Plant Taxonomy
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• v.43 no.2
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• pp.81-89
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• 2013

In general, studies of aerial parasitic plants known collectively as mistletoe have been carried out to investigate their ecological and agricultural characteristics. However, with the recently increased level of interest in medicinal resources, research on different types of Korean mistletoe has also increased. This study was carried out to review the work on the taxonomy and ecology of Korean mistletoe in preparation for the industrial use of these plants in the future. Mistletoe types are flowering plants belonging to Santalales, which exist in the form of parasites on the branches of trees or shrubs. In Korea, five taxa of four genera in two families of mistletoe exist: Viscum coloratum (Komarov) Nakai f. coloratum, Viscum coloratum (Komarov) Nakai f. rubroaurantiacum (Makino) Kitagawa and Korthalsella japonica (Thunb.) Engl. in Santalaceae, along with Loranthus tanakae Franch. et Sav. and Taxillus yadoriki (Sieb. ex Maxim.) Danser in Loranthaceae. As taxonomic studies of these species remain insufficient and given that the distribution ranges of these species are very wide, further observations pertaining to the morphological variations in each species are necessary. The distribution of mistletoes is known to be determined by the host specificity, the interval between the hosts, the environmental condition, the habits of the host plant, the eating characteristics of mediators in the area, and their habitat selection features.

• Journal of Acupuncture Research
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• v.32 no.3
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• pp.163-173
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• 2015

Objectives : The aim of this study is to determine whether Chinemys reevesii Gray pharmacopuncture is a clinically effective treatment for women with knee osteoarthritis. Methods : Female patients with knee osteoarthritis were recruited from May $1^{st}$, 2014 to April $15^{th}$, 2015 at the Department of Acupuncture & Moxibustion Medicine of Dong-Eui University Korean Medical Hospital. Patients were randomly assigned to two groups. 4.0 ml of Chinemys reevesii Gray pharmacopuncture was injected at acupuncture points of the experimental group(n = 24) twice a week for three weeks. The control group(n = 24) received 5 % dextrose injections in order to identically stimulate the same acupuncture points of $ST_{35}$, $ST_{34}$, $SP_9$, $SP_{10}$, $GB_{34}$, $LR_8$, $EX-LE_4$, and $EX-LE_2$. The Short-Form McGill Pain Questionnaire(SF-MPQ), the Korean Western Ontario and McMaster Universities Osteoarthritis Index(KWOMAC), and the European Quality of Life-5 Dimensions(EQ-5D) were recorded to evaluate treatment efficacy at first visit, after two weeks and four weeks from the initial visit. Results : 40 patients completed the trial. The experimental group showed more significant improvement than the control group in the scores of SF-MPQ, KWOMAC, and EQ-5D. However, there was no significant difference between groups in a few of the assessment scales. Conclusions : Chinemys reevesii Gray pharmacopuncture can be an effective treatment in control of pain, improvement in function and health-related quality of life for women with knee osteoarthritis.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.34 no.1
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• pp.17-25
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• 2012

Purpose: Recently, a three dimensional approach to hard and soft tissues of the maxillofacial area has been widely used. This study was to evaluate the reproducibility and accuracy of a stereocamera compared to actual measurement methods using a digital caliper and digitizer. Methods: The stereoscopies of 7 head dummies with different sizes and shapes were obtained using a Di3D system (Dimensional Imaging, Glasgow, UK) after marking reference points on facial areas. From the obtained stereoscopy, 10 measurements representing the width, height and depth of each of the facial sections of the dummy were measured twice using a three dimensional reverse engineering software program (RapidForm$^{TM}$ 2006, Inus, Seoul, Korea). The x, y, and z coordinates of each of the three dimensional measurements were obtained and distances between two points were calculated. All procedures were repeated twice. The actual measurement method was performed twice, directly on dummies, using a digital caliper and values were compared with the previously determined values. Results: The results were as follows. In the ANOVA analysis, there were no significant statistical differences among the three measurement methods. In the Bonferroni analysis, with adjustments applied for multiple comparisons, there was no difference between actual measurement methods using a digitizer and a digital caliper. However, there was some difference between using a stereocamera and actual measurement methods using a digitizer and a digital caliper in values of $Ex_{Rt}-Ex_{Lt}$, $En_{Rt}-En_{Lt}$, $Ala_{Rt}-Ala_{Lt}$, $Ch_{Rt}-Ch_{Lt}$, G-Pg', $Ala_{Rt}$-Prn, $Ala_{Rt}$-Prn. The mean value for technical error in measurement (TEM) in Di3D (0.98 mm) was slightly higher than for a digital caliper (0.17 mm) and a digitizer (0.30 mm). In an intraclass correlation coefficient (ICC) there were no significant differences among the three measurement methods, but the Di3D system with the stereocamera showed relatively lower reproducibility compared to actual measurement methods using a digitizer and a digital caliper. Conclusion: These results indicate that some complementary measures may be needed to improve accuracy and reproducibility in the Di3D system with stereocamera.