• Title/Summary/Keyword: CV characteristics

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Stem Rot of Kalanchoe Caused by Phytophthora nicotianae (Phytophthora micotianae 에 의한 칼랑코에 역병)

  • 한경숙;이중섭;지형진
    • Research in Plant Disease
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    • v.7 no.1
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    • pp.8-10
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    • 2001
  • A stem and root rot disease of kalanchoe (Kalanchoe sp.) which is a succulent plant that provides consumers with a durable flowering pot was found in Koyang, Kyounggi province, Korea in May 1998. We found that stems and roots of potted kalanchoe had dark brown spots at the soil level. The causal organism was identified as Pjytophtora nicotianae on the basis of mycological characteristics. The fungus produced markedly papillate, ovoid to spherical sporangia, and abundant chlamydospores. Sporangia were 20∼48$\times$24∼64㎛(avg. 35.0$\times$47.3㎛) in size, and optimum temperature for the mycelial growth of the isolate was 30$\^{C}$. The fungus showed relatively different pathogenicity to 14 kalanchoe cultivars including K. blossfelana cv. Florus. cultivars florsu, calypso, Maya, and Redsing were susceptible to thedisease in root dip inoculation. This is the first report demonstrating the stem rot on kalanchoe caused by P. nicotianae in Korea.

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Gray Mold of Statice (Limonium shinuatum) Caused by Botrytis cinerea in Korea (Botrytis cinerea에 의한 스타티스 잿빛곰팡이병)

  • Kwon, Jin-Hyeuk;Park, Chang-Seuk
    • Research in Plant Disease
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    • v.10 no.2
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    • pp.117-120
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    • 2004
  • In April of 2003, the gray mold disease occurred severely on statice (Limonium shinuatum Mill. cv. Sophia) grown in the commerical farms in Seosang-myon, Hamyang-gun, Gyeongnam Province, Korea, 2003. The infected plants were started with water-soaking lesions in the stems, the leaves and the flowers became withered and discolored to gray or dark from the tip then gradually expanded to die. The conidia and mycelia of the pathogen appeared on flowers, leaves, calyx and flower stalk. The conidia were gray, I-celled, mostly ellipsoid or ovoid in shape and were 8∼20 x 6∼14 ${\mu}{\textrm}{m}$ in size. Conidiophores were 14∼34 ${\mu}{\textrm}{m}$ in size. The sclerotia were formed abundantly on potato-dextrose agar. The optimum temperature for sclerotial formation was 2$0^{\circ}C$. Pathogenicity of the causal organism was proved according to Koch's postulate. The causal organism was identified as Botrytis cinerea Persoon: Fries based on mycological characteristics. This is the first report on gray mold of statice (Limonium shinuatum) caused by Botrytis cinerea in Korea.

Korean Phonetic Characteristics reflected in the Pronunciation of French (한국인의 불어발음에 나타나는 음성학적 특징)

  • Park Hay-Jeanne
    • Proceedings of the KSPS conference
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    • 1996.10a
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    • pp.252-257
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    • 1996
  • La structure syllabique est un facteur important dan la prononciation d'une langue. Dans cette these, on a essaye de montrer que les caracteristiques de la syllabe varie d'une langue a une autre, et que les regles qui regissent la syllabe dan la langue maternelle a le dessue et done fait appliquer ses regles a la langue etrangere. Premierement, l'accentuation du coreen depend de la structure syllabique (qu'elle soit consonne-voyelle(CV) ou consonne-voyelle-consonne(CVC) et de la longueur de la voyelle. Ce qui fait que bien que le francais soit oxyton, et que la longueur et la qualite de la voyelle dependent de la structure syllabique, le francais, le francais parle par les coreens suit les regles du coreen. Autre caracteristique est que le coreen n'admet pas de suite de consonnes avant et apres la voyelle centrale comme dans "premier"[$pr{\partial}mje$] "autre"[o:tR]. D'ou l'insertion de voyelle superflue comme [${\varpi},{\;}{\wedge},{\;}{\partial}$]. Troisiemement, il existe une difference dans la coupe de la chaine parlee: en coreen la coupe ecrite(le blanc) egale a peu pres a la coupe orale(la pause) alors qu'en francais, c'est en groupe de mots que se fait la coupe. A l'interieur du groupe, les mots sont lies entre eux, soity par liaison, soit par enchainement. On peut remarquer donc une nette influence du coreen, ou la regle est de prononcer correctement par unites ecrites (equivalent des mots en francais) : la chaine parlee devient saccadee, avec un accent sur tous les mots, et des coups de glotte entre les mots, et l'une des voyelles [${\varpi},{\;}{\wedge},{\;}{\partial}$] inseree entre un mot se terminant par une consonne suivi d'un mot qui commence par une consonne.

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Characteristics of Resistance to Potato Virus Y in Transgenic Tobacco Plants Mediated with Complimentary DNA (cDNA) of PVY Replicase Mutant Genes

  • Chae, Soon-Yong;Park, Eun-Kyung;Kim, Young-Ho;Kim, Sang-Seock;Paek, Kyung-Hee
    • Journal of the Korean Society of Tobacco Science
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    • v.20 no.1
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    • pp.57-65
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    • 1998
  • This study was conducted to develop a resistant tobarro against Potato virus Y (PVY) by transformation of the plants with genetically engineered viral genes. The complimentary DNAs (cDNAS) of potato virus Y-necrosis strain (PVY-Vn) replicase mutant genes (3'-deleted, 5'-deleted and ADD-mutant Nlbs) were synthesized through RT-PCR by using purified PVY-VN RNA and synthesized primers, and cloned in the sense orientation into a plant expression vector (pMBPI), The cDNAS of the genes were transferred into Agrobacterium tumefaciens LBA 4404, and then transformed into tobacco (Nicotiana tabacum cv. Burley 21) plants. Regenerated plants were tested for PVY resistance by inoculation test; 13 transgenic plants including 7 for 3'-deleted Nlb, 3 for 5'-deleted Nlb, and 3 for ADD-mutant Nlb appeared to be resistant at 4 weeks after inoculation with PVY-VN. Among the 13 transgenic tobacco plants, 8 plants had no symptom up to 14 weeks after inoculation. The progenies ($T_1$) from self-fertilization of the transgenic lines varied 0.0% to 81.2% in their resistance (% of resistant plants). The analysis of Nlb-31deleted, -5'deleted and -ADD mutant in the $T_1$ plants by polymerase chain reaction (PCR) showed that Nlb-3'deleted, -5'deleted and -ADD mutants were detected in all of the resistant plants. These results suggest that the PVY resistance was inherited in the $T_1$ generation.

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Design and Implementation of 3.3 kW On-Board Battery Charger for Electric Vehicles (전기자동차용 3.3 kW 탑재형 배터리 충전기 설계 및 제작)

  • Kim, Jong-Soo;Choe, Gyu-Yeong;Jung, Hye-Man;Lee, Byoung-Kuk;Cho, Young-Jin
    • The Transactions of the Korean Institute of Power Electronics
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    • v.15 no.5
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    • pp.369-375
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    • 2010
  • This paper presents a design and implementation of 3.3 kW on-board battery charger for electric vehicles or plug-in hybrid electric vehicles. Considering characteristics of the electric vehicles, a series-loaded resonant dc-dc converter and frequency control scheme are adopted to improve efficiency and reliability, and to reduce volume and cost. The developed on-board battery charger is designed and implemented by using high frequency of 80-130 kHz and zero voltage switching method. The experimental result indicates 92.5% of the maximum efficiency, 5.84 liters in volume, and 5.8kg in weight through optimal hardware design.

Biochemical, Microbiological, and Sensory Characteristics of Stirred Yogurt Containing Red or Green Pepper (Capsicum annuum cv. Chungyang) Juice

  • Kang, Su-Hyun;Yu, Mi-Sang;Kim, Jeong-Mee;Park, Sung-Kwon;Lee, Chi-Ho;Lee, Hong-Gu;Kim, Soo-Ki
    • Food Science of Animal Resources
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    • v.38 no.3
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    • pp.451-467
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    • 2018
  • Hot pepper has anti-obesity effects by controlling appetite and reducing blood fat level. To reduce the pungency of capsaicin, red or green hot pepper juice was fermented with Bacillus licheniformis SK1230. Fermented hot pepper juice was then added into yogurt at different ratios. The pH of yogurt added with hot pepper juice was decreased from 4.61 to 4.48. Titratable acidity and counts of lactic acid bacteria were increased with increasing amount of pepper juice added. However, the viscosity was decreased significantly compared to the control. On chromaticity test, when more pepper juice was added, $L^*-value$ was decreased whereas $a^*$- and $b^*$- values were increased significantly (p<0.05). The spectrum of antimicrobial activity of yogurt was slightly changed compared to using pepper juice. Total polyphenol contents and antioxidant activity were increased with increasing amount of pepper juice added. Stirred yogurt added with fermented red pepper juice at 3% or green pepper juice at 1% showed high scores in flavor, appearance, texture, and overall acceptance in sensory test. Yogurt added with fermented pepper juice with reduced pungency showed also good palatability during storage at $4^{\circ}C$. Yogurt with added hot pepper juice can be play an important role in functional food relative to anti-obesity.

Fabrication of Pt-Ru/C Composite Catalyst Electrodes by Electrophoresis Deposition Method for DMFC Fuel Cell and their Characteristics (전기영동법에 의한 직접메탄올 연료전지용 Pt-Ru/C 복합촉매 전극제조 및 특성평가)

  • Kim, Jeonghyun;Song, Minkyeong;Kim, Jinwoo;Yu, Yeontae
    • 한국신재생에너지학회:학술대회논문집
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    • 2011.11a
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    • pp.86.2-86.2
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    • 2011
  • 저온형 연료전지인 직접 메탄올 연료전지(Direct Methanol Fuel Cells, DMFC)는 친환경적인 발전 시스템, 높은 에너지 효율의 장점 때문에 주목을 받고 있으나 연료극의 촉매로 사용되는 금속은 고가의 귀금속인 Pt와 Ru가 요구되어 제조비용이 비싸기 때문에 촉매의 양을 줄이고, 반응 도중 생성되는 CO에 의한 촉매의 피독 문제 등 해결하여야 할 점이 산적해 있어 연료전지 중 촉매의 활성을 높이는 연구들이 활발히 이루어지고 있다. 종래의 MEA의 촉매층 제조공정은 우선 환원석출법에 의해 Pt-Ru/C를 합성하고 Nafion 용액에 혼합하여 Pt-Ru/C 슬러리를 제조한다. 이 방법에서는 carbon sheet에 spray 방법으로 Pt-Ru/C 촉매층이 만들어지기 때문에, Pt-Ru 촉매가 Nafion에 의해 부분적으로 매몰되어 촉매의 전기화학적 활성이 떨어지는 문제점이 있다. 이를 해결하는 방안으로 펄스전류를 이용하여 Pt-Ru 합금입자를 carbon sheet에 전기화학적으로 담지 시켜 Nafion에 매몰되는 것을 방지하는 펄스전해법 연구가 진행되고 있다. 그러나 촉매의 입자크기가 일반적으로 50~70 nm 이상으 크기 때문에 촉매의 낮은 활성이 문제점으로 야기되고 있다. 본 연구에서는 Pt-Ru/C 촉매층 제조 문제점을 해결하고, 촉매의 전기화학적 활성을 증가시키기 위해서 2~4 nm Pt-Ru 콜로이드를 전해액으로 사용하고, 전기영동법을 이용하여 Pt-Ru 나노 입자를 carbon sheet($1{\times}1cm^2$) 에 담지 시켰다. 전기영동법에서 균일한 Pt-Ru 촉매층의 제조를 위해 전류인가 방법으로는 펄스전류를 사용하였고, 실험변수로는 전해액 pH, duty cycle, 담지시간을 선정하였다. 합성된 Pt-Ru 콜로이드를 TEM분석으로 나노입자의 크기와 분산성 분석하였고, 콜로이드 나노입자의 표면전하 상태를 분석하기 위해 zeta-potential을 분석하였다. Pt-Ru/C의 촉매의 전기화학적 활성을 분석하기 위하여 0.5 M H_2SO_4$ 와 1 M $CH_3OH$ 혼합용액에 CV(Cyclic Voltammetry)실시하였고, carbon sheet 전극 상 Pt-Ru의 분산성 확인을 위하여 FE-SEM분석을 수행하였다.

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The Electrochemical Characteristics of 9-methyl-2,3,6,7-tetramethoxyfluorene in CH3CN and CH2Cl2/TFA/TFAn-solvent Mixture (CH3CN과 CH2Cl2/TFA/TFAn-혼합용매계에서의 9-methyl-2,3,6,7-tetramethoxyfluorene의 전기화학적 특성)

  • Kim, Duk-Hyun;Kim, Su-Jin
    • Applied Chemistry for Engineering
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    • v.10 no.2
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    • pp.196-200
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    • 1999
  • The electrochemical properties of 9-methyl-2,3,6,7-tetramethoxyfluorene have been investigated by cyclic voltammetry in acetonitrile, dichloromethane, trifluoroacetic acid (TFA) and trifluoroacetic acid anhydride (TFAn). The first charge transfer for the compound in $CH_3CN$ appeared to be a quasi-reversible one-electron step. The second oxidation step from cation to dication was irreversible. However, the oxdition of the compound in a mixture of solvents containing $CH_2Cl_2$, TFA and TFAn was reversible for both the first and second charge transfer reactions. Since the electrolytic products display a darkblue color and can be stabilized in the solvent mixture, they may be used as an electrochromic material.

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Effect of Cutting Height on C and N Reserves and Consequent Regrowth in Frequently Defoliated Turf-Type Perennial Ryegrass(Lolium perenne L.) (잔디형 페레니얼 라이그라스에서 잦은 예취조건하의 예취높이가 저장 탄수화물과 단백질 함량 및 재생에 미치는 영향)

  • 김대현;정우진;이복례;김길용;김태환
    • Journal of The Korean Society of Grassland and Forage Science
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    • v.21 no.2
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    • pp.89-96
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    • 2001
  • Carbohydrate and soluble protein reserves and regrowth characteristics in response to cutting height were investigated over four regrowth cycles of turf-type perennial ryegrass(Lolium perenne L. cv. preludeII). When the plants were at the full-vegetative stage (twelve weeks-old), three sequential defoliations at 3, 6 and 9 cm above the root base were imposed at 2-week intervals. Shoot dry weight in all three treatments continuously decreased with progressing regrowth cycle and the decreasing rate was higher as cutting height was lowered. TNC (total non-structural carbohydrate) in stubble at the end of the fourth regrowth cycle in 3, 6 and 9 cm cutting height decreased by 98%, 82% and 27%, respectively, comparing the initial content. TNC in roots also largely decreased with similar pattern in response to cutting height, whereas the absolute amount was much less compared to stubble. Soluble protein in stubble in 3, 6 and 9 cm cutting height decreased by 98%, 82% and 57%, respectively, at the end of fourth regrowth. A significant correlations between TNC (r=0.906) or protein (r=0.879) at the fourth defoliation and dry weight of regrowing shoots at the end of fourth regrowth were observed. these results indicated that cutting height closely influences the levels of organic reserves available for new growth, and that the levels of reserves might provide a useful tool as a determinant for regrowth dynamics.

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A Philological Study on the Pathology, Acupuncture and Moxibustion of Alopecia (탈발(脫髮)의 병인병기(病因病機) 및 침구치료(鍼灸治療)에 관한 문헌고찰)

  • Lee, Sang Hyun;Cho, Myoung Rae
    • Journal of Acupuncture Research
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    • v.32 no.2
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    • pp.35-57
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    • 2015
  • Objectives : The purpose of this study is to analyze literature on oriental medicine to investigate the pathology, acupuncture, and moxibustion therapy applicable to alopecia Methods : We searched for the causes of alopecia in the bibliographic data from 41 sources of literature and the acupunctural treatments for alopecia in the bibliographic data from 49 sources of Chinese and Korean literature and from the journals of the acupunctural treatments for alopecia which have been published since 2000. Results : 1. The main causes of alopecia are blood deficiency, blood heat, static blood, depletion of kidney's water, wind excess, seven emotional damage, dietary damage, etc. 2. The acupuncture points frequently used are $GV_{20}$, $GB_{20}$, $ST_{36}$, $SP_6$, $SP_{10}$, $BL_{17}$, $BL_{18}$, $BL_{23}$, $GV_{23}$, $GV_{14}$, $CV_6$, $ST_8$, $KI_3$, $LR_3$, $HT_7$, $LI_{11}$, EX-$HN_1$, and ouch point. 3. New acupuncture therapies, including herbal acupuncture therapy, ear acupuncture therapy, dermal needle therapy, needle-embedding therapy and scalp acupuncture therapy are frequently used to treat alopecia. Conclusions : The acupuncture points frequently used for treating alopecia have characteristics such as tonifying blood, tonifying the liver and kidney, extinguishing wind, activating blood, clearing heat and draining dampness, so they are highly associated with the causes and the mechanisms of alopecia.