• 제목/요약/키워드: Mean weight diameter

검색결과 161건 처리시간 0.023초

유기물 처리가 간척지 토양의 입단형성에 끼치는 영향 (Effect of Organic Material Treatments on Soil Aggregate Formation in Reclaimed Tidelands)

  • 손재권;조재영
    • 한국토양비료학회지
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    • 제42권3호
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    • pp.201-206
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    • 2009
  • 신선유기물 (이탈리안 라이그라스), 신선유기물 + 부산물비료 그리고 부산물비료 처리 후 3년 동안 토양입단 발달상태를 조사한 결과, 토양별로는 모래 함량이 상대적으로 높은 새만금 간척지 토양 보다는 미사와 점토함량이 높은 고흥 간척지 토양에서의 입단형성이 더 양호한 것으로 나타났다. 유기물 자원 처리별로는 고흥 간척지 토양에서는 유의성 있는 차이가 나타나지 않았으나 (P<0.05), 새만금 간척지 토양에서는 녹비 형태의 신선 유기물 즉, 이탈리안 라이그라스를 처리한 시험구에서 가장 입단화도가 높게 나타났다. 유기물 종류별로는 이탈리안 라이그라스와 같은 신선 유기물을 단독 처리한 시험구에서 토양 입단의 중량평균직경이 가장 크게 나타났다. 간척지 토양의 물리성 및 토양구조 개선을 위한 유기물 처리시 신선유기물의 처리가 바람직하며, 불가피할 경우 일반 유기질/부산물비료의 단독처리보다는 신선유기물과 혼합하여 처리하는 것이 타당한 것으로 조사되었다.

대두직물의 황토염색 (Loess Dyeing of Soybean Fabrics)

  • 이솔;이신희
    • 한국의류산업학회지
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    • 제17권6호
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    • pp.1004-1012
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    • 2015
  • The purpose of this study is to investigate the loess dyeability of soybean fabric using loess as colorants. Recent days, various textile products such as inner wears, sheets and interior goods are manufactured using materials dyed with loess emphasizing its improved metabolism, anti-bacterial, deodorizing properties, and far infrared ray emissions. Soybean fabric was dyed with loess solution according to concentration of loess, dyeing temperature and dyeing time. To improve washing fastness, soybean fabric and dyed soybean fabric with loess were mordanted by mordanting agents such as sodium chloride(NaCl), Acetic acid(CH3COOH) and Aluminium Potassium Sulfate(AlK(SO4)2·12H2O). Dyeability and color characteristics of dyed soybean fabric were obtained by CCM observation. Particle size distribution of loess, the dyeability(K/S) of soybean fabric, morphology and washing durability of loess dyed soybean fabric were investigated. The results obtained were as follows; Mean average diameter of loess was 1.08µm. The main components of loess used in this study were silicon dioxide(SiO2), aluminium oxide(Al2O3), and iron oxide(Fe2O3). The content of these three component was above 75 weight %. The dyeability of soybean fabric was increased gradually with increasing concentration of loess. The optimum dyeing temperature and dyeing time were 90℃ and 60minutes expectively. The fastness to washing according to concentration of loess and mordanting method indicated good grade result as more than 4 degree in all conditions.

Sequential Conjugation of 6-Aminohexanoic Acids and L-Arginines to Poly(amidoamine) Dendrimer to Modify Hydrophobicity and Flexibility of the Polymeric Gene Carrier

  • Yu, Gwang-Sig;Yu, Ha-Na;Choe, Yun-Hui;Son, Sang-Jae;Ha, Tai-Hwan;Choi, Joon-Sig
    • Bulletin of the Korean Chemical Society
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    • 제32권2호
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    • pp.651-655
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    • 2011
  • We synthesized a novel cationic dendrimer consisting of a poly(amidoamine) dendrimer (PAMAM, generation 4) backbone with both L-arginine (Arg) at the termini and 6-aminohexanoic acid (Ahx) between the original core polymer and the peripheral Arg units. The sequential chemical modification of PAMAM G4 with Ahx and Arg resulted in higher transfection efficiency with much less cytotoxicity. PAMAM G4-Ahx-Arg formed stable polyplexes at weight ratios of 8:1 or higher (polymer: plasmid DNA), and the mean polyplex diameter was $180{\pm}20nm$. PAMAM G4-Ahx-Arg showed much higher transfection ability than PAMAM G4 or PAMAM G4-Ahx. Furthermore, PAMAM G4-Ahx-Arg was much less cytotoxic than PEI25KD and PAMAM G4-Arg. In addition to Arg grafting of the PAMAM dendrimer, which endows a higher transfection capability, the addition of Ahx spacer increased dendrimer hydrophobicity, introduced flexibility into the conjugated amino acids, and reduced cytotoxicity. Overall, it appears that the concomitant modification of PAMAM with Ahx and Arg could lead to new PAMAM conjugates with better performances.

Morphological Characteristics of Korean Dried Ginseng Products

  • Hong, Hee-Do;Cho, Chang-Won;Kim, Young-Chan;Kim, Eun-Young;Rhee, Young-Kyung;Rho, Jeong-Hae;Choi, Seung-Hoe
    • Journal of Ginseng Research
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    • 제36권3호
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    • pp.314-321
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    • 2012
  • The purpose of this study was to determine a standard quality characteristic through the evaluation and statistical analysis of the morphological characteristics of dried ginseng (white ginseng) products. Samples of 4-year-old 30 and 50 piece grade curved ginseng and 5-year-old 25 and 15 piece grade straight ginseng products were collected from a market, with 5 to 10 packs of each product being collected annually over a 5-year period (2006-2010). Morphological characteristics, such as weight, length, diameter, and surface color, were measured and statistically analyzed to present a standard quality characteristic value using $mean{\pm}3SD$, a range that excluded outlier. The 4-year-old curved ginseng samples of 50 and 30 piece grade were 4.80 to 6.12 cm and 5.28 to 7.60 cm long, 0.22 to 1.70 cm and 0.21 to 2.07 cm wide, and weighed 5.28 to 7.40 g and 8.62 to 12.26 g, respectively. The 5-year-old straight ginseng samples of 25 and 15 piece grade were 9.66 to 15.47 cm and 10.66 to 16.80 cm long, 1.32 to 1.94 cm and 1.48 to 2.43 cm wide, and weighed 9.18 to 16.40 g and 15.89 to 24.82 g, respectively. The surface color of the different piece grades in the same type of dried ginseng product was similar, whereas the straight ginseng demonstrated a lower level of brightness, but the relative redness and yellowness were of higher levels, than that of curved ginseng.

함티탄자철광 Slag의 유동층 염소화에 의한 TiCl4의 제조 (The Production of TiCl4 from Titaniferrous Magnetite Slag by the Chlorination in a Fluidized Bed Reactor)

  • 송기영;이상순;이철태
    • 공업화학
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    • 제4권1호
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    • pp.64-74
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    • 1993
  • 국내 부존 함티탄자철광으로부터 염화티타늄($TiCl_4$)을 제조키 위해 함티탄자철광의 arc-smelting으로부터 얻어지는 titanium slag의 유동층 염소화 반응을 조사하였다. Titanium slag의 유동층 염소화반응에 적절한 반응조건은 반응 온도 $950^{\circ}C$, 반응시간 90분, 염소가스의 유속 3.0cm/sec, titanium slag에 대한 petroleum coke의 무게비 0.18, 그리고 titanium slag 및 petroleum coke의 입자의 평균직경은 각각 $44.6{\mu}m$, $67.9{\mu}m$였다. 위 조건하에서 titanium slug 중의 97.07%의 티타늄이 염소화 되었으며 제조된 염화티타늄($TiCl_4$)의 순도는 96.2%였다.

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녹조류 참홑파래 (Monostromu nitidum)의 생태와 초기생장 (Ecology and Early Growth of Monostroma nitidum (Ulvales, Chlorophyta) in Korea)

  • 윤장택;조용철;공용근;정규화
    • 한국수산과학회지
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    • 제39권5호
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    • pp.419-426
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    • 2006
  • This study investigated the ecology and growth of Monostroma nitidum Wittrock in both its natural habitat and the laboratory. The maximum length, width, and weight of M. nitidum in March were 9.0$\pm$4.7 cm, 9.6$\pm$3.6 cm, and 1.52$\pm$1.13 g, respectively. Yellowish-green or yellowish-brown reproductive thalli began to appear in January, and over 80% of the thalli matured by March. The male and female spores were ca. 6 $\mu$m long, and elongate and ovoid in shape. The spores had two flagella and one-eye spot, and tended to swim toward light. Maximum number of spores released from matured thalli was 236 cells/mL after 70 minutes at a light intensity of 100 $\mu$mol/m$^2$/s. The zygote diameter ranged from 3.4-6.0 $\mu$m (mean 4.2 $$m) and increased to 69.8 $\mu$m 14 weeks after culture. The mass release of zoospores was observed from thalli in the dark (3 to 12 days), after 30 min under dry conditions in the shade, at 25$^{\circ}C$, and a light intensity of 100 $\mu$mol/m$^2$/s. The maximum number of zoospores released was 109.8 cells/mL after 60 min of induction. M. nitidum fronds on the net increased to 6.8-7.2 cm in length, and 6.6-8.9 cm in width during the winter.

고밀도 뱀장어 양식수조의 질병대책 (Fish Diseases and Their Control in High Density Culture of Eel)

  • 전세규
    • 한국수산과학회지
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    • 제16권2호
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    • pp.103-110
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    • 1983
  • The main purpose of the present study is to evaluate a revolving plate type biofilter system for mass culture of eel(Anguilla japonica) based on the experimental rearing for 120 days (Oct. 1982-Feb. 1983). Water quality changes, growth efficiency of fish and fish disease treatment were critically evaluated. A revolving plate type biofilter system was designed(Fig. 1). The system consisted of a glass tank (150 l), a revolving plate biofilter and a settling tank(150 l). The biofilter consisted of 60 submerged quadriangular plates ($28{\times}37$ cm) and 30 revolving plates (32 cm diameter) for a total of 19.0 $m^2$ of surface area. The revolving plates were made to rotate 10 time per minute, The total water volume of the rearing system were 300 l, and everyday 1/3 of the total water volume were changed with freshly prepared water. In the rearing system a total of 2 kg of eel (1,500 individuals, mean weight:1.3 g) were reared fed on the pellet feed and the dough feed. The growth efficiency were much better for the pellet feed (FC: 1.79) compared to the dough feed (FC: 3.56). During the experimental rearing water quality control was satisfactory. Total ammonia concentrations were 0.38-0.59 ppm and nitrite concentration were 0.83-1.19 ppm. On the other hand alkalinity decreased from 176ppm just after the water change to 17ppm just before the water change. The low alkaline condition was compensated by the regular change of water. Epidemics of parasitic gill-flocks (Pseudodactvlogylus sp.) was observed, and they were easily eliminated by the treatment of DDVP (1.0 ppm). Trichodina sp. and Costia sp. were observed, and they were also controlled by the treatment of potassium permanganate (4.0 ppm).

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필러의 실란처리농도가 복합레진의 특성에 미치는 영향 (INFLUENCES OF SILANE CONCENTRATION FOR FILLER SILANIZATION ON THE PROPERTIES OF COMPOSITES)

  • 조태희;박상진
    • Restorative Dentistry and Endodontics
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    • 제26권1호
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    • pp.23-31
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    • 2001
  • The purpose of this study was to search the optimal silane concentrations for filler- silanization of seven experimental composites. Silica filer was a 25micron crushed type. 0.0%, 0.5%, 1.0%, 1.5%, 2.0%, 2.5%, and 3.0% silane($\gamma$-methacrylooxypropyltrimethoxysilane)were added into silica-filler with weight percentage (wt%). Mixtures(silica filler/silane)were reacted at 6$0^{\circ}C$ for 72hours, and crushed into fine particles those were used as fillers for 7 experimental composites. Monomer was a 3 : 1 mixture of Bis-GMA and TEGDMA containing 0.2% tertiary amine and 0.4% camphoroquinone for light curability. A ratio for mixing the monomer and filler was 75% and 25% respectively. Seven experimental composites was classified with the concentration of silane treated, and the specimen number for each test was 10. Specimens with 6mm diameter and 3mm height dimension for measuring the diametral tensile strength were destroyed with 1mm/min cross-head speed on Instron universal testing machine (No. 4467, USA). Shear bond strength was measured on the specimens bonded to bovine enamel etched with 37% phosphoric acid solution for 1 minute Fractured surfaces were observed by SEM (Hitachi S-3200, Japan) among that of the highest values measured from each groups. Following results were obtained: 1. Experimental composites containing silanized filter showed the significantly higher diametral tensile strength and shear bond strength than the composites containing un-silanized fillers(Group1) (p<0.05). 2. In silanized filler composite resins(Group 2~7), Diametral tensile strength of Group 3 showed the significantly higher than that of Group 2 and Group 6(p<0.05). 3. Shear bond strength was higher in Group 3 than that of Group 7 (p<0.05)in silanized fillers composite resins. 4. Fracture surface was formed in resin matrixes on the specimens from composites containing the fillers treated with 0.5% 1.0%, and 1.5% silane. These results mean that the optimal silane concentrations are exist for each fillet with its size and surface area, and that 1.0% is a optimal value for concentration to coat the 25$\mu\textrm{m}$ filler with silane.

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Outcomes of transcatheter closure of ductus arteriosus in infants less than 6 months of age: a single-center experience

  • Choi, Gwang-Jun;Song, Jinyoung;Kim, Yi-Seul;Lee, Heirim;Huh, June;Kang, I-Seok
    • Clinical and Experimental Pediatrics
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    • 제61권12호
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    • pp.397-402
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    • 2018
  • Purpose: Transcatheter device closure of patent ductus arteriosus (PDA) is challenging in early infancy. We evaluated PDA closure in infants less than 6 months old. Methods: We performed a retrospective review of infants less than 6 months of age who underwent attempted transcatheter device closure in our institution since 2004. To compare clinical outcomes between age groups, infants aged 6-12 months in the same study period were reviewed. Results: A total of 22 patients underwent transcatheter PDA closure during the study period. Patient mean age was $3.3{\pm}1.5months$, and weight was $5.7{\pm}1.3kg$. The duct diameter at the narrowest point was $3.0{\pm}0.8mm$ as measured by angiography. The most common duct type was C in the Krichenko classification. Procedural success was achieved in 19 patients (86.3%). Major complications occurred in 5 patients (22.7%), including device embolization (n=1), acquired aortic coarctation (n=2), access-related vascular injury requiring surgery (n=1), and acute deterioration requiring intubation during the procedure (n=1). Two patients had minor complications (9.1%). Twenty-four infants aged 6-12 months received transcatheter device closure. The procedural success rate was 100%, and there were no major complications. The major complication rate was significantly higher in the group less than 6 months of age (P=0.045). There was a trend toward increased major complication and procedural failure rates in the younger age group (P<0.01). Conclusion: A relatively higher incidence of major complications was observed in infants less than 6 months of age. The decision regarding treatment modality should be individualized.

Distribution of the Genetic Resource and the Biomass of Root Bark of Ulmaceae Species

  • Park, Dong Jin;Yong, Seong Hyeon;Yang, Woo Hyeong;Seol, Yuwon;Choi, Eunji;Kim, Hyeong Ho;Ahn, Mi-Jeong;Choi, Myung Suk
    • 농업생명과학연구
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    • 제53권2호
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    • pp.65-75
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    • 2019
  • Stem and root of elm trees have used as traditional medical materials, but there is little information on the distribution and resources of habitats. Korean native growing Ulmus spp. (U. davidiana var. Japonica, U. parvifolia, U. davidiana, and U. macrocarpa) genetic resources studied through The National Forest Inventory of Korea data and field survey. The distributions of U. davidiana var. japonica according to elevation distributed evenly. Both U. parvifolia and U. davidiana were inhabited mostly at less than 200 m of altitude. Each Ulmaceae species widely were distributed nationwide, but a dominant species was different depending on locals. It observed that Ulmaceae inhabits mainly in steep slopes of 31-45 degrees. Most of the habitats regenerated by natural seeding and the most abundant species were a codominant tree. Distribution of trees in U davidiana var. japonica was 7 m-13 m, and in young U. parvifolia and U. macrocarpa, more than 25% of young trees less than 7 m observed. The distribution of the diameter of breast height of the U. davidiana var. japonica was 46.4% for 11-20 cm, 52.6% for 11-20 cm in U. parvifolia. The average T/R ratio was 0.83, and the mean weight ratio of root bark was 62%. As the results of this study, the domestic Ulmaceae biomassare very small. It is difficult to harvest in that the habitat on the slope. Thus, it is too hard to develop functional materials using biomass at present. Therefore, it is necessary to develop technology for the selection and propagation of elite trees of Ulmaceae.