• Title/Summary/Keyword: effective diameter

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Effects of Solar Heating for Control of Pink Root and Other Soil-borne Diseases of Onions

  • Lee, Chan-Jung;Lee, Jong-Tae;Moon, Jin-Seong;Ha, In-Jong;Kim, Hee-Dae;Kim, Woo-Il;Cheon, Mi-Geon
    • The Plant Pathology Journal
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    • v.23 no.4
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    • pp.295-299
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    • 2007
  • These experiments were carried out to examine efficacy of soil solarization for control of pink root disease by means of mulching with transparent polyethylene sheets in the hot season. The effects of soil solarization on incidence of pink-root disease caused by Pyrenochaeta terrestris and on onion growth and on populations of soil fungi were investigated. Solarization was dramatically effective in reducing pink root incidence in onion seedling and harvested onion bulb. A 30-day and 40-day solarization treatment significantly improved seedling survival and increased yield of 'Changnyeong-deago' onion while decreasing incidence of pink root. Populations of soil fungi from fields planted to onion were assayed on selective media. Solarization treatment was effective in reducing populations of P. terrestris, Pythium spp., and Rhizoctonia sp. in soil. Increase of yield of onion bulbs was associated with control of soil-borne pathogenic fungi. Soil solarization had beneficial effects on yield, bulb diameter, or incidence of pink root.

Study on the spectroscopic reconstruction of explosive-contaminated overlapping fingerprints using the laser-induced plasma emissions

  • Yang, Jun-Ho;Yoh, Jai-Ick
    • Analytical Science and Technology
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    • v.33 no.2
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    • pp.86-97
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    • 2020
  • Reconstruction and separation of explosive-contaminated overlapping fingerprints constitutes an analytical challenge of high significance in forensic sciences. Laser-induced breakdown spectroscopy (LIBS) allows real-time chemical mapping by detecting the light emissions from laser-induced plasma and can offer powerful means of fingerprint classification based on the chemical components of the sample. During recent years LIBS has been studied one of the spectroscopic techniques with larger capability for forensic sciences. However, despite of the great sensitivity, LIBS suffers from a limited detection due to difficulties in reconstruction of overlapping fingerprints. Here, the authors propose a simple, yet effective, method of using chemical mapping to separate and reconstruct the explosive-contaminated, overlapping fingerprints. A Q-switched Nd:YAG laser system (1064 nm), which allows the laser beam diameter and the area of the ablated crater to be controlled, was used to analyze the chemical compositions of eight samples of explosive-contaminated fingerprints (featuring two sample explosive and four individuals) via the LIBS. Then, the chemical validations were further performed by applying the Raman spectroscopy. The results were subjected to principal component and partial least-squares multivariate analyses, and showed the classification of contaminated fingerprints at higher than 91% accuracy. Robustness and sensitivity tests indicate that the novel method used here is effective for separating and reconstructing the overlapping fingerprints with explosive trace.

Preharvest Drop Control of 'Tsugaru' Apple with Combined Use of Aminoethoxyvinylglycine and Several Adhesive Agents (Aminoethoxyvinylglycine과 몇몇 전착제의 혼용처리에 의한 '쓰가루' 사과의 수확전 낙과방지)

  • Kang, Chung Kil;Chae, Yun Seok;Kim, Su-Jeong
    • Horticultural Science & Technology
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    • v.17 no.6
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    • pp.750-752
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    • 1999
  • This experiment was conducted to evaluate preharvest drop control in 'Tsugaru' apple with combined treatments of aminoethoxyvinylglycine (AVG) and several adhesive agents. AVG+Silwet L-77 at $75+1,000mg{\cdot}L^{-1}$ was most effective among the tested combinations. Little or no significant difference was observed among the different application times of AVG+Silwet L-77. AVG+Silwet L-77 significantly reduced preharvest drop while increasing fruit weight, fruit length, diameter and fruit firmness. All the tested combinations were generally effective in reducing preharvest drop as compared to dichlorprop and in maintaining better fruit quality.

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Effect of Welding Parameters on Wire Seam Weldability of Tin Coated Steels for Small Containers (용접 조건이 소형 용기용 Sn 도금 강재의 와이어 심 용접성에 미치는 영향)

  • 김기철;이기호;이목영
    • Journal of Welding and Joining
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    • v.15 no.5
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    • pp.74-83
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    • 1997
  • Effect of welding parameters such as current, speed and electrode pressure on the weld quality of tin coated steels for small containers was discussed in this paper. Welding was performed with low frequency wire seam welding system which was loaded with 1.5mm in diameter copper wire electrode. The welding parameters were monitored at the position close to the welding spot so as to minimize the instrumentation error, and the signals were stored into a digital data acquisition system before analysis. Results showed that critical current for sufficient nugget size increased as the base material thickness increased, while the width of the optimum welding range was reduced. The acceptable welding condition derived from this study was found to be effective within the thickness range of $\pm$10% of the nominal (0.25mm) thickness. Tin coating layer was proved not to affect seriously on the weld quality, i.e. strength and formability, since consumable wire electrode was used in this process. Test results also demonstrated that the welding current was thought to be the most effective parameter to form an acceptable weld, while welding speed or electrode pressure exerted less effect on the nugget formation. However, these two parameters played an important role because the former was related to the nugget overlap interval, and the latter, to the formation of expulsion during welding.

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Stereocomplex Poly(lactic acid) Discoidal Microparticles for Sustained Drug Release (약물지연방출을 위한 스테레오컴플렉스 PLA 원반형 마이크로입자)

  • Park, Chaewon;Park, Sanghyo;Kim, Woo Cheol;Key, Jaehong
    • Journal of Biomedical Engineering Research
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    • v.41 no.1
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    • pp.62-66
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    • 2020
  • Controlled drug release is important for effective treatment of cancer. Poly(DL-lactide-co-glycolide) acid (PLGA) is a Food and Drug Administration (FDA) approved polymer and have been extensively studied as drug delivery carriers with biodegradable and biocompatible properties. However, PLGA drug delivery carriers are limited due to the initial burst release of drug. Certain drugs require an early rapid release, but in many cases the initial rapid release can be inefficient, reducing therapeutic effects and also increasing side effects. Therefore, sustained release is important for effective treatment. Poly Lactic Acid stereo complex (PLA SC) is resistant to hydrolysis and has high stability in aqueous solutions. Therefore, in this work, PLGA based discoidal polymeric particles are modified by Poly Lactic Acid stereocomplex (PLAsc DPPs). PLAsc DPPs are 3 ㎛ in diameter, also showing a relatively sustained release profile. Fluorescein 5(6)-isothiocyanate (FITC) released from PLAsc DPPs was continuously observed until 38 days, which showed the initial release of FITC from PLAsc DPPs was about 3.9-fold reduced as compared to PLGA based DPPs at 1 hour.

Gold Storage and Cryopreservation of Grey Mullet(Mugil cephalus) Sperm (숭어(Mugil cephalus) 정자의 냉장.냉동보존)

  • 장영진;최윤희;임한규;고강희
    • Journal of Aquaculture
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    • v.12 no.1
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    • pp.57-62
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    • 1999
  • Experiments were performed to study the activity and fertility of grey mullet (Mugil cephalus) sperm after the courses of cold storage and cryopreservation. The head of spermatozoon showing spherical shape was sized $1.26{\pm}0.08 \{mu}textrm{m}$ in diameter and its nucleus contained numerous granular chromatins. Flagellum of tail showed typical 9+2 structure. Preservation of grey mullet sperm was the most effective when it was stored with serum of the same species at $0^{\circ}C$ and sperm activity index was similar in egg-tris, 0.1 M, 0.3 M and 0.5 M glucose. When grey mullet sperm were cryopreserved in MFRS as diluent with 10% dimethyl sulfoxide was effective compared with other diluents. Some of post-thawed spermatozoa showed the enlarged head and ruptured plasma membrane compared with unfrozen spermatozoa.

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The Effects of Copolymer Additives for Drag Reduction on Turbulent Flow (합성고분자첨가제의 난류마찰저항 감소효과 연구)

  • Kim, N.S.;Kim, C.B.;Kim, I.S.;Choi, H.J.
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.5 no.3
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    • pp.207-216
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    • 1993
  • Experimental investigations have been carried out to find the effect of drag reduction caused by effective polymer additives in turbulent flows. The experiments were undertaken with a test section of 9.8mm pipe diameter and 3500 mm pipe length(L/D=357) in a closed loop, and Copolymer-X and Polyacrylamide(PAAM) were used as polymer additives for comparisons. The tests were carried out under different polymer concentrations, and the temperatures of the flow considered were $26^{\circ}C$, $60^{\circ}C$ at the flow velocity of 5.3 m/s. The rate of drag reduction obtained by Copolymer-X is found to be considerably higher than that of PAAM in turbulent flows. Copolymer-X is also found to be very reliable for mechanical degradation, which has not been the case in any other additives. It is concluded that Copolymer-X is considered to be one of the most effective agents as an additive especially for long time hydraulic transports. It is also found that polymer degradation in more likely at lower polymer concentrations in the turbulent flows.

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A Experimental study for obtaining material function of very soft clay (초연약 점토의 구성관계 산정에 관한 실험적 연구)

  • Lee, Song;Kang, Myung-Chan
    • Proceedings of the Korean Geotechical Society Conference
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    • 2002.03a
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    • pp.491-498
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    • 2002
  • Dredged and reclaimed soft clays form slurry state which is very high water content and very low shear strength, experience large self-weight consolidation, nonlinear compressibility and permeability phenomenon would take place. In this case, a material functions which represent variety effective stress-void ratio-permeability relation (especially very low effective stress), are should be determined to predict nonlinear finite strain consolidation phenomenon forehand In this study, large slurry consolidometer with a 380mm diameter and a 1400mm height which is able to consolidation and permeability test, was developed to determine material function of very soft clay with a 500% initial water content clay, self-weight consolidation and low stress level consolidation (1Kpa, 3Kpa, 6Kpa, 12Kpa) was conducted and after each consolidation step permeability test also conducted. after final consolidation step, a constant rate of strain consolidation was conducted with undisturbed sample obtained from the large consolidometer. On the above result, material function was determined and laboratory test was modelled to evaluate its validity, numerical analysis on th field was compared to other method.

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Antifungal Effect of Sanguisorba officinalis L. fractions on Candida albicans (지유 분획의 Candida albicans에 대한 항균효과)

  • Lee, Jae-Hyeok;Choi, Bong-Sil;Park, Jeong-Sook;Shin, Tae-Yong
    • Korean Journal of Pharmacognosy
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    • v.48 no.2
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    • pp.166-171
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    • 2017
  • We have studied the antifungal effect of 19 medicinal plants with paper disc diffusion method against candida albicans. As a result, Sanguisorba officinalis L., Cinnamomum cassia, Rheum coreanum, Perilla frutescens and Eugenia caryophyllata have been found to be effective against C. albicans. Among these, Sanguisorba officinalis L. was most effective at 24 hours and 48 hours. Its clear zone diameter was 17 mm for 24 hours and 16 mm for 48 hours. The antifungal activity of the solvent fraction of Sanguisorba officinalis L. by n-hexane, chloroform, ethyl acetate and n-butanol was the best for the chloroform fraction of 28 mm for 24 hours and 18 mm for 48 hours. The MIC concentration of the chloroform fraction was $80{\mu}g/50{\mu}l$ at 24 hours and $240{\mu}g/50{\mu}l$ at 48 hours.

Effects of Foliar Spray of CCC [(2-Chloroethyl)-trimethyl-ammonium Chloride] on the Growth of Mulberry Tree and Metabolic Activities in the Leaves. (CCC[(2-Chloroethyl) trimethyl-ammonium chloride]의 엽면살포가 상수의 생장 및 생체내 대사에 미치는 영향)

  • 이재와
    • Journal of Sericultural and Entomological Science
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    • v.22 no.1
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    • pp.46-51
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    • 1980
  • The effects of foliar Spray of CCC [(2-Chloroethyl)-trimethyl-ammonium Chloride] on the growth of mulberry tree and the metabolic activities in the leaves were measured. The results of this experiment are summarized as follows; 1. Foliar application of CCC was not effective in increasing of leaf area, the fresh and dry weight of the leaves and height of shoot, but was effective in increasing of diameter of Shoot. 2. Chlorophyll Content was generally increased in all treated leaves 3. All the treated leaves were lower in GOT and GPT activity than control leaves. 4. The activities of hydrolytic reducing Sugar in the mulberry leaves infiltrated Sucrose were lower than those of the control in all treated leaves, but the activities on Synthetic non-reducing Sugar in the mulberry leaves infiltrated glucose were higher than those of control in all treated leaves.

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