• 제목/요약/키워드: 18-crown-6

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Research on the Distribution and Damage of the Fall Webworm Hyphantria cunea Durury (미국 흰불나방의 피해(被害)와 분포조사(分布調査))

  • Ko, Jeho;Lee, Sangok
    • Journal of Korean Society of Forest Science
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    • v.7 no.1
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    • pp.35-39
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    • 1968
  • 1. The Fall webworm, Hyphantria cunea was widely distributed ranging from Seoul to Kangnung, Yung-ju, Taegu, Iri and Kwang-ju in 1967. 2. Heavily infested tree species by the Fall webworm were Sycamore, Cherry, ash-leaved maple, poplar, and elm. 3. The average number of larval masses per damaged garden tree and roadside tree was 7.0 and 3.4 respectively. 4. Trees of 6-10m in height had most number of larval masses and were most heavily infested. 5. More larval masses were found in the median and lower parts than higher parts of the crown. 6. The ratio of damaged by second generation was 55% higher than by first generation. The ratio of damage by 3rd generation is 18% less than by first generation.

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Alkali Metal Ion Catalysis in Nucleophilic Substitution Reactions of 5-Nitro-8-quinolyl Benzoate with Alkali Metal Ethoxides in Anhydrous Ethanol: Unusually High Na+ Ion Selectivity

  • Um, Ik-Hwan;Lee, Seung-Eun;Hong, Yeon-Ju;Park, Jee-Eun
    • Bulletin of the Korean Chemical Society
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    • v.29 no.1
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    • pp.117-121
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    • 2008
  • Pseudo-first-order rate constants (kobsd) have been measured spectrophotometrically for nucleophilic substitution reactions of 5-nitro-8-quinolyl benzoate (5) with alkali metal ethoxides, EtO?M+ (M+ = Li+, Na+ and K+) in anhydrous ethanol (EtOH) at 25.0 0.1 C. The plots of kobsd vs. [EtO?M+] exhibit upward curvatures, while the corresponding plots for the reactions of 5 with EtO?Na+ and EtO?K+ in the presence of complexing agents, 15-crown-5-ether and 18-crown-6-ether are linear with rate retardation. The reactions of 5 with EtO?Na+ and EtO?Li+ result in significant rate enhancements on additions of Na+ClO4, indicating that the M+ ions behave as a catalyst. The dissociated EtO and ion-paired EtOM+ have been proposed to react with 5. The second-order rate constants for the reactions with EtO (kEtO) and EtOM+ (kEtOM+) have been calculated from ion-pairing treatments. The kEtO and kEtOM+ values decrease in the order kEtONa+ > kEtOK+ > kEtOLi+ > kEtO, indicating that ion-paired EtOM+ species are more reactive than the dissociated EtO ion, and Na+ ion exhibits the largest catalytic effect. The M+ ions in this study form stronger complex with the transition state than with the ground state. Coordination of the M+ ions with the O and N atoms in the leaving group of 5 has been suggested to be responsible for the catalytic effect shown by the alkali metal ions in this study.

Comparison of Physicochemical Properties and Antioxidant Activity between Raw and Heat-Treated Vegetables (열처리한 채소류의 이화학적 특성 및 항산화 활성 비교)

  • Kim, So-Young;Lee, Young-Min;Kim, Jong-Bong;Park, Dong-Sik;Go, Jeong-Sook;Kim, Haeng-Ran
    • The Korean Journal of Community Living Science
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    • v.25 no.1
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    • pp.5-18
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    • 2014
  • This study examines the changes in the physicochemical property and antioxidant activity of six types of vegetables (carrots, crown daisy, mugwort, cabbages, onions, and garlic) based on heat-treated cooking. According to the results, proximate contents (crude protein, fat, and ash) were lower in blanched samples than in untreated samples. Untreated cabbages showed the highest level of total dietary fiber content, which decreased by blanching and increased by high-temperature/high-pressure (HTHP) treatment. Noteworthy is that, in the case of soluble dietary fiber, blanched crown daisy and mugwort showed significantly high levels of 12.0 g and 7.3 g per 100 g(dry basis). There was no significant change in tocopherol content in heat-treated samples. The highest levels of total polyphenol and flavonoid content were 6.73 g and 5.51 g per 100 g, respectively, in the mugwort sample with HTHP treatment at $130^{\circ}C$ for 2 h. The water extract of mugwort with HTHP treatment had the strongest antioxidant effect based on three bioassays (SOD, DPPH, and ABTS). These results indicate the relative correlation between the level of physiologically active content and antioxidant activity and suggest new insights into ingredients for developing functional foods.

A new manufacturing method of all ceramic restoration using alumina tape and presentation of clinical cases

  • Oh, Nam-Sik;Kim, Eui-Seong;Lee, Keun-Woo;Han, Jung-Suk;Kim, Dae-Joon;Lee, Myung-Hyun
    • The Journal of Korean Academy of Prosthodontics
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    • v.38 no.6
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    • pp.800-805
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    • 2000
  • In an effort to facilitate fabrication procedure of all ceramic crowns, a novel preparation method for all ceramic crown using alumina tape was developed. The alumina tape having a uniform thickness was cast by using Doctor blade method. The physical properties of newly introduced alumina tape has biaxial flexure strength of $500\sim600MPa$. The value of toughness is $3.18\sim3,28MPa.m^{1/2}$ which corelates with fracture and the linear shrinkage rate of the alumina tape is 0.44% during core production. The marginal fitness of the alumina tape all-ceramic restoration with $90{!`}$shoulder margin had average marginal discrepancy at $78.3{\S}$ > and average marginal gap at $44.4{\S}$ >. At the marginal preparation of $135{!`}$deep chamfer, the average marginal discrepancy at $82.1{\S}$ > and the average marginal gap at $40.2{\S}$ > had been reported. This fabrication procedure of all ceramic crowns with alumina tapes is easier and less technical sensitive for dental technicians. After restoration with new all ceramic crowns we followed the patients 2 years later, there were no complications as porcelain fractures or periodontal disease. We had good esthetic clinical results with new all ceramic crowns.

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Development and growth of the temporal fascia: a histological study using human fetuses

  • Kei Kitamura;Satoshi Ishizuka;Ji Hyun Kim;Hitoshi Yamamoto;Gen Murakami;Jose Francisco Rodriguez-Vazquez;Shin-ichi Abe
    • Anatomy and Cell Biology
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    • v.57 no.2
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    • pp.288-293
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    • 2024
  • The temporal fascia is a double lamina sandwiching a thick fat layer above the zygomatic bony arch. To characterize each lamina, their developmental processes were examined in fetuses. We observed histological sections from 22 half-heads of 10 mid-term fetuses at 14-18 weeks (crown-rump length, 95-150 mm) and 12 near-term fetuses at 26-40 weeks (crown-rump length, 215-334 mm). The superficial lamina of the temporal fascia was not evident at mid-term. Instead, a loose subcutaneous tissue was attached to the thin, deep lamina of the temporal fascia covering the temporalis muscle. At near-term, the deep lamina became thick, while the superficial lamina appeared and exhibited several variations: i) a mono-layered thick membrane (5 specimens); ii) a multi-layered membranous structure (6) and; iii) a cluster of independent thick fasciae each of which were separated by fatty tissues (1). In the second and third patterns, fatty tissue between the two laminae was likely to contain longitudinal fibrous bands in parallel with the deep lamina. Varying proportions of the multi-layered superficial lamina were not attached to the zygomatic arch, but extended below the bony arch. Whether or not lobulation or septation of fatty tissues was evident was not dependent on age. The deep lamina seemed to develop from the temporalis muscle depending on the muscle contraction. In contrast, the superficial lamina developed from subcutaneous collagenous bundles continuous to the cheek. Therein, a difference in development was clearly seen between two categories of the fasciae.

Comparison of Analysis Model on Soil Disaster According to Soil Characteristics (지반특성에 따른 토사재해 해석 모델 비교)

  • Choi, Wonil;Baek, Seungcheol
    • Journal of the Korean GEO-environmental Society
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    • v.18 no.6
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    • pp.21-30
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    • 2017
  • This study analyzed the ground characteristics region by designating 3 research areas, Anrim-dong in Chungju City, Busa-dong in Daejeon Metropolitan City and Sinan-dong in Andong City out of the areas subject to concentrated management to prepare for sediment disaster in downtown areas. The correlation between ground characteristics were observed by using characteristics (crown density, root cohesion, rainfall characteristics, soil characteristics) and the risk areas were predicted through sediment disaster prediction modeling. Landslide MAPping (LSMAP), Stability Index MAPping (SINMAP) and Landslide Hazard MAP (LHMAP) were used for the comparative analysis of the hazard prediction model for sediment disaster. As a result of predicting the sediment disaster danger, in case of SINMAP which was generally used, excessive range was predicted as a hazardous area and in case of the Korea Forest Service's landslide hazard map (LHMAP), the smallest prediction area was assessed. LSMAP predicted a medium range of SINMAP and LHMAP as hazardous area. The difference of the prediction results is that the analysis parameters of LSMAP is more diverse and engineering than two comparative models, and it is found that more precise prediction is possible.

RELATIONSHIP BETWEEN THE DEVELOPMENTAL STAGE AND CHRONOLOGICAL AGE, AND THE CHANGES OF TOOTH POSITION IN RELATION TO THE TOOTH DEVELOPMENT ON MANDIBULAR PERMANENT TEETH (하악 영구치아의 발육과 연령과의 관계 및 치아 발육에 따른 치아의 위치 변화)

  • Kim, Hyun-Mi;Yang, Seung-Duck;Kim, Hyun-Jung;Kim, Young-Jin;Nam, Soon-Hyeun
    • Journal of the korean academy of Pediatric Dentistry
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    • v.29 no.4
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    • pp.607-617
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    • 2002
  • The purposes of this study were to evaluate the timing of tooth calcification and the change of tooth position with tooth developmental stage on the mandibular teeth. Seven hundred seventy two children(male:446, female:326), 3 to 12 years of age were examined radiographically with panoramic film. Dental development was determined by inspecting radiographs and assigning a rating according to consecutive stages defined by Moorrees, and tooth cusp position and root terminus position were measured from the lower border of mandibular body and calculated the position index to evaluate the movement of tooth with developmental stage. The results were as follows. 1. There were no significant differences between boys and girls in the timing of calcification until crown completion, but timing of calcification tend to be faster in girls than in boys after root initiation stage. 2. In terms of mean age, crown completion of central incisor in boys and girls occurred at the age of 3.71, 4.05 years, at 4.44, 4.60 years for the lateral incisor, at 5.35, 5.11 years for the canine, at 6.62, 6.36 years for the first premolar, at 7.36, 7.17 years of second premolar, at 3.51, 3.69 years of first molar, and at 7.90, 7.64 years for the second molar respectively. Apex 1/2 closed stage of central incisor occurred at the age of 8.70 in boys, 8.18 in girls, at 9.55, 8.99 years for the lateral incisor, at 12.48, 11.60 years for the canine, at 12.30, 12.01 years for the first premolar, at 12.19, 12.26 years of second premolar, at 9.12, 8.87 years of first molar, and at 12.59, 12.45 years for the second molar respectively. 3. There was no noticeable movement of cusp tip until crown completion (Crc), but showed rapid movement toward occlusion plane after root initiation(Ri) and again maintain stable position after root completion stage(Rc). 4. Root terminus position was stable until root 1/4 formation stage(R1/4), followed by rapid movement toward occlusal plane and was stable again after root 3/4 formation stage(R3/4). 5. Developmental stage at the time of alveolar bone penetration by cusp tip varied with each of the permanent teeth. 6. Canine tooth follicle was at the lowest position in the mandibular body during the early stage of calcification, followed by second premolar, first premolar, lateral incisor, second molar, first molar and central incisor in order.

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Determination of Betaine from Saliconia herbacea L. (함초(Saliconia herbacea L.)로부터 베타인 정량)

  • Lee, Chang-Ho;Kim, In-Ho;Kim, Young-Eon;Oh, Se-Wook;Lee, Ho-Jun
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.33 no.9
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    • pp.1584-1587
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    • 2004
  • The betaine content of Saliconia herbacea L. was determined by reverse-phase high performance chromatog-raphy on a C_(18) column. A 50% methanol extract was passed through a anion exchanger Ambelite IRA 400 (quaternary ammonium type, OH-) column and a strong cation exchanger Ambelite IR 120 (sulfonic acid type, $H^+$) column to remove amino acids, zwitter ions which are interfere with betaine analysis. The betaine extract was derivatized with 18-crown-6-ether and 4-bromophenacyl bromide (PBPB) for UV-labelling. Betaine in Saliconia herbacea L. was analysed on a mobile phase contained 13 mM sodium heptane sulfonic acid and 5 mM $Na_2SO_4$ in deionized water by isocratic elution for 30 min. The recovery ratio of betaine from Saliconia herbacea L. extract was 83.6%. The mean betaine value for Saliconia herbacea L. determined by the described method is 4.85 mg/mL with a standard deviation of 0.127.

Studies on the Ecological Changes in the Plant Community of the Erosion Controlled Area at Yoju-Gun, Kyonggi-Do (사방시공지(砂防施工地) 식물사회(植物社會)의 생태학적(生態學的) 변화(變化)에 관(關)한 연구(硏究)(II) - 경기(京畿), 여주지역(驪州地域)을 중심(中心)으로 -)

  • Lee, Hyun Kyu
    • Journal of Korean Society of Forest Science
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    • v.81 no.4
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    • pp.303-309
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    • 1992
  • This study eras carried out to investigate the ecological changes on the plant community at erosion controlled area in Yoju-gun, Kyonggi-do. The results of the study were as follows : 1. The depth of organic matters in the soil profile from 4 to 14 years was estimated to be $Y_{(cm)}=0.436X_{(yr)}-0.931$(r=0.978), and 02 layer was $Y_{(cm)}=0.339_{(yr)}-0.931$ (r=0.954). 2. On upper plant layer. Alnus spp. was decreased, on an average, 32% of relative coverage, 12.4% of relative density and 16.8% of relative frequency in each plot for 3 years, as this area was damaged by Agelastica coerulea Baly for 2-3 years. 3. On upper plant layer, relative coverage of Pinus spp. was increased after 6, 7 years in erosion controlled area and was taked the highest plant (more then 40%) from 10 to 14 years. 4. On lower plant layer, relative density of Quercus ssp. (these species has not been planted and sown on erosin controlling) was increased all the plot. 5. The increase of the whole crown projection area was estimated to be $Y_{(m^2)}=18.020X_{(yr)}+18.834$(r=0.954) 6. The biomass was estimated to be 14.88t/ha on elapsed 6 years, 22.84t/ha on 8 years, 35.08t/ha on 10 years, 47.80t/ha on 12 years, 58.13t/ha on 14 years.

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Simultaneous Determination of Anions and Cations in Natural Water by Ion-exclusion/Cation-exchange Chromatography with a Weakly Acidic Cation-exchange Resin Column

  • Lee, Kwang-Pill;Choi, Seong-Ho;Park, Yu-Chul;Bae, Zun-Ung;Lee, Mu-Sang;Lee, Sang-Hak;Chang, Hye-Yong;Kwon, Se-Mok;Kazuhiko Tanaka
    • Bulletin of the Korean Chemical Society
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    • v.24 no.9
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    • pp.1324-1328
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    • 2003
  • The simultaneous determination of anions ($SO_4 ^{2-},\;Cl^-,\;and\;NO_3^-$) and cations ($Na^+,\;NH^{4+},\;K^+,\;Mg^{2+},\;and\;Ca^{2+}$) in natural water obtained by Nakdong River waters system in Korea were performed by ion-exclusion/cationexchange chromatography with conductimetric detection. The stationary phase was a polymethacrylate-based weakly acidic cation-exchange resin column in the $H^+$-form and a weak-acid eluent. When using only a 1.4 mM sulfosalicylic acid/6 mM 18-crown-6 ether as an eluent, good resolution of both anions and cations, minimum time required for the separation, and satisfactory detection sensitivity were obtained in a reasonable time. The method was successfully applied to the simultaneous determination of anions and cations in natural waters.