• Journal of the Korean Society of Propulsion Engineers
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• v.6 no.3
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• pp.9-17
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• 2002

This Study is to investigate 8 composite propellants including Butacene and ${Bi_2}{O_3}$ by Shotgun/RQ Bomb test. Burning rate and mechanical properity are known to be major factors in determining the deflagrability of propellant. Propellant including over 5.5% Butacene(Ferrocene grafted HTPB) burned out over 135 m/s of impact velocity during Shotgun/RQ Bomb test. It was blown that Butacene was very sensitive material under high velocity impact. In the test results, propellants under 25mm/s in burning rate at 1500 psia could meet the requirements for IM of UN Test Series 7c(ii). Propellant deflagrabillity depends on burning rate at performance in the results of the present.

• Journal of the Korean Chemical Society
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• v.65 no.5
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• pp.320-326
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• 2021

This study investigated the effect of the structure of the crosslinking agent used in contact lens polymerization on the physical properties and drug dissolution of contact lenses.es Contact lenses were manufactured using 0.3% and 3% of 4 types of crosslinking agents, respectively, and ofloxacin was used as the drug. Contact lenses using hydrophilic crosslinking agents improved water contents and wettability, and the more hydrophilic functional groups, the greater the effect. Contact lenses with a high concentration of crosslinking agent had a low concentration of eluted drug and a longer release time. The cross-linking agent structure of contact lenses had an effect on improving the performance of contact lenses and controlling drug release.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.48 no.4
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• pp.321-330
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• 2022

This study attempted to establish an optimal multi-compound simultaneous analysis method that can secure reliable results for 15 - preservatives, 2 - sun screens and 1 - antioxidants of cosmetics using HPLC-PDA. Since the potential of hydrogen (pH) in the mobile phase affects the acid dissociation constant (pKa) of the preservatives, and the peak retention time shift and area change were observed. The peak separation condition was established by adjusting the pH to 0.1% H₃PO₄ addition (mL) when preparing the mobile phase. As a results of method validation, the linearity correlation coefficient (R²) of above 0.999 were obtained, and accuracy 87.9 ~ 101.1%, 0.1 ~ 7.6% precision for two types of cosmetics (cream and shampoo). It was found that the limit of detection (LOD) was 0.1 ~ 0.2 mg/kg and the limit of quantitation (LOQ) was 2.0 ~ 4.0 mg/kg. In addition, it was possible to simultaneously separate p-anisic acid, a natural compound that was difficult to separate in HPLC due to the small difference from methylparaben, a synthetic preservatives. Through this study, it will be effectively used to secure quality control and safety for compound that need restrictions on use cosmetics.

• The Korean Journal of Zoology
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• v.37 no.2
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• pp.161-173
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• 1994

면역효소법을 이용하여 3종의 한국산 개구리 참개구리(Rono nigromaculuto), 옴개구리(R. rugosa), 북방산개구리(R. 겨대bowskii)의 뇌에서 GnRH 뉴우런의 분포 부위와 GnRH의 종류 등을 연구하였다. 1차 항체로는 anti-rat GnRH, anti-salmon GnRH anti-chicken 11 GnRH 항체를 사용하였다. 3종의 개구리에서 mGnRH cGnRH 11와 sGnRH가 이둔 동정되었으나 3가지 항체에 대한 각 종의 면역 반응성은 종에 따라 달리 나타났다 mGnRH는 옴개구리와 참개구리에서, sGnRH는 북방산개구리에서 강한 면역 반응을 나타냈으며 cGnRH 11는 3종의 개구리에서 중간 정도의 면역 반응을 나타냈다. 각각의 GnRH의 상대적인 양에는 차이가 있으나 일부 경우를 제외하고는 뇌의 동일한 지역에 분포하였다. 참개구리에서는 GnRH가 중격 내측핵(NMS), Broca band 핵(NDB)에 집단으로 분포하였다. 북방산개구리에서는 GnRH가 중격 내측핵, Broca bnad 핵에서 등쪽에서 배쪽으로 길게 선상으로 가장 협소하게 분포하였으며, 번식기와 직전(1월-3월)에만 면역 반응을 나타냈다. 옴개구리의 뇌에서 가장 광범위한 지역, 즉 종뇌의 중격 내측핵, Broca band 핵, 아래 교차 지역(SCA)과 간뇌에 GnRH 신경세포가 분포하였으며. 제3뇌실 맥락얼기에서 mGnRH 신경세포가 처음으로 동정되었다. 3종에서 공통적으로 중격 내측핵과 Broca band 핵에서 유래한 신경섬유는 복측 시상하부를 거쳐 정중융기에 이르렀다. 이러한 결과는 GnRH가 뇌하수체에서 생식소 자극 호르몬의 분비 조절에 밀접한 관계가 있음을 뜻한다.

• Animal Systematics, Evolution and Diversity
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• v.18 no.2
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• pp.233-244
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• 2002

As one of the serial studies on the taxonomy of Conthocamptus mirabilis species group in South Korea, C. semicirculus Kikuchi, widely distributed in the southern part of the Far East, and C. coreensis n. sp. from the middle west of South Korea are recorded. Intraspecific variability of some important characters like outer caudal setae and the spinous process of male leg 3 exopod was examined in Korean population of C. semicirculus. Canthocamptus coreensis n. sp. possesses the plesiomorphic characters of the round and narrow hyaline membrane of anal operculum and lacking the sexual reverse transformation in female caudal rami, while it also evolves the apomorphic ones of the modified outer apical setae of male leg 4 exopod and the spinous process of male leg 3 exopod. A key to the five species of the species group known from Korea is prepared.

• Horticultural Science & Technology
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• v.31 no.5
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• pp.633-639
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• 2013

Fungicide applications are required to prevent the strawberry from Botrytis fruit rot and powdery mildew that infect open strawberry flowers, however, their effects of fungicides on pollen germination of strawberry have been rarely documented, particularly those from recently developed active fungicidal ingredients. In this study we have evaluated the effects of 24 commercial fungicidal formulations and 6 organic materials on pollen germination in 3 strawberry cultivars using in vitro assays. Pollens from strawberry had higher germination rates on agar with sucrose of 18% and $25^{\circ}C$ than other tested conditions. Pollen germination rates of cvs. Seolhyang, Maehyang, and Kumhyang at 18% sucrose and $25^{\circ}C$ were 15.3, 18.4 and 30.7%, respectively. Pyraclostrobin, azoxystrobin, kresoxim-methyl, dichlofluanid, iminoctadine tris, and sulfur showed the strongest inhibitory efficacy with the germination rates of more than 93.8% compared to the no-fungicide control. Germination was not significantly affected by simeconazole and procymidone. This in vitro germination study may provide information useful for selecting fungicides in flowering stage to strawberry farmers.

• Korean Journal of Environment and Ecology
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• v.33 no.2
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• pp.178-186
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• 2019

This study used the probit analysis to evaluate the toxicity of three chemicals - benomyl (Germicide), carbofuran (insecticide), and thiobencarb (herbicide) - with the FETAX (Frog Embryo Teratogenesis Assay-Xenopus) protocol using the incubated embryos of tree frog, Hyla japonica. The results showed that the larval body length decreased while the mortality and malformation rates increased as the concentrations of benomyl, carbofuran, and thiobencarb increased. The teratogenic concentration ($EC_{50}$) of benomyl, carbofuran, and thiobencarb were 1.00, 0.58, 4.75 mg/L, respectively, indicating that the malformation of larvae was the most sensitive to carbofuran. The embryo lethal concentration ($LC_{50}$) was 7.04, 28.71, and 16.12mg/L, respectively, indicating that benomyl showed the lowest embryo lethal concentration. The teratogenic index (TI) was 7.04 in Benomyl, 49.50 in Carbofuran, and 3.39 in Thiobencarb, indicating that the TI values were above 1.5, which is the criterion of teratogenicity, for all three chemicals. All three pesticides examined by this study were considered to be the most teratogenic substances, and the carbofuran was the most potent teratogen.

• Proceedings of the KOR-BRONCHOESO Conference
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• 1981.05a
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• pp.8.5-9
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• 1981

Foreign body in the esophagus is not uncommon in the otolaryngological field and esophageal perforation followed by mediastinitis is one of the most serious complications. Authors had experienced such case developed in 69 year old female patient. This woman swallowed a piece of sharp glass accidentally. Severe pain and swelling around the neck developed after ingestion. Marked subcutaneous emphysema was noted on first examination. By esophagoscopy, longitudinal laceration at right lateral wall of the cervical esophagus was noted and a lot of food debries were removed through this perforation, but foreign body could not be found. On third hospital day, patient complained chest pain and dyspnea. Mediastinal widening was noted on chest P-A. Tracheostomy was performed on next day and neck swelling decreased much. In spite of massive antibiotics, mediastinal abscess was developed and external drainage was performed on 15th hospital day. She was discharged on 38th hospital day with marked improvement and recovered completely on follow-up study. Still, we do not know where the foreign body is located.

• The Korean Journal of Pesticide Science
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• v.11 no.3
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• pp.144-153
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• 2007

One of the most recent issues facing the pesticides regulatory process is the assessment of the potential for pesticides to leach through soil and appear in groundwater. Since Jeju island depends on a hydrogeologically vulnerable aquifer system as its principle source of drinking water, it is important to identify which pesticides are the most likely to result in groundwater contamination. The objective of this study was to assess groundwater contamination risk of 21 pesticides (12 insecticides, 6 herbicides and 3 fungicides) in Jeju soils using groundwater ubiquity score (GUS). Considering GUS estimated in 21 representative series of Jeju soils, generally herbicides showed relatively higher leaching potentials and insecticides showed lower leaching potentials. Groundwater contamination risk was higher in the order of bromacil > metolachlor > alachlor > linuron pretilachlor > butachlor for herbicides, carbofuran > ethoprophos > diazinone > dimethoate > penthoate > mecarbam > methidathion > endosulfan > fenitrothion > parathion > chlorpyrifos > terbufos for insecticides, and metalaxyl > chlorothalonil > triadimefon for fungicides. Among the tested pesticides alachlor, metolachlor, bromacil, ethoprophos and carbofuran were classified as the pesticides of very high or high groundwater contamination potential. Although the ranking of the leaching potential was essentially determined on the base of the intrinsic properties of the chemicals and environmental properties, variation of the relative groundwater contamination potentials of each pesticides in different soils were not significant. Therefore, the above ranking of groundwater contamination risk would be applied in most of Jeju soils. To lower the possibility of pesticide contamination of groundwater, the use of those pesticides classified as high or very high leaching potential should be strictly regulated in Jeju Island.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.41 no.6
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• pp.704-709
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• 1996

This experiment was carried out to establish the system of mass propagation through tissue culture using sucker and stem in Ramie. The sterilization for tissue culture of Ramie was the better treatment of 2% NaClO for 20 minute into ultrasonic cleaner than the others, and so rate of contamination was 3.3%, and it was able to produce 96% healthy plant. The effect of growth regulator was superior to mixed treatment of 0.02mg/$\ell$ NAA, 1.5mg/$\ell$ BA, 0.lmgmg/$\ell$ GA$_3$, which it was not formed callus and but produced 96% healthy plant. The effect of propagation was higher in culturing of the stem node than the sucker in cultural part, local variety than improved ones. The effect of acclimatization was superior to pretreatment of 30 minute after soaking in 100ppm NAA, transplanting on bed soil which mixed to ratio of vermiculite : soil : sand =1 : 2 : 1, the transplanted plants were grown all normal.