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착색단고추 재배 온실의 피복재 종류에 따른 내부 온.습도 변화 (Change of Internal Temperature and Humidity According to Kind of Covering Materials in Sweet Pepper's Greenhouse)

  • 김호철;최준혁;이수원;이정현;배종향
    • 생물환경조절학회지
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    • 제19권1호
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    • pp.1-5
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    • 2010
  • 착색단고추가 재배되고 있는 유리 온실과 플라스틱 필름 온실을 대상으로 내부 온 습도 변화 및 식물체 생육의 차이를 알아보고자 수행하였다. 재배 기간 동안 일평균 내부온도는 두 온실 간 차 이를 나타내지 않았으나, 그 변화폭은 플라스틱필름 온실에서 심하였다. 그리고 온실 내 수분부족분은 유리 온실에서 4.3$g{\cdot}m^{-2}$, 플라스틱필름 온실에서 5.6$g{\cdot}m^{-2}$로 플라스틱 필름 온실에서 더 많았다. 외부 광 1w에 대한 내부 온도 변화는 유리온실보다 플라스틱필름 온실에서 2배 정도 빨리 증가하는 경향이었다. 특히, 이러한 차이에는 일몰 전 후보다 일출 후 초기의 온도 차이가 가장 크게 영향을 주었다. 이에 따라 플라스틱 필름 온실보다 유리 온실에서 잎의 생육 및 광합성산물 생산율이 더 높았고, 생산성도 80% 정도 더 높았다. 이로 보아 유리 온실 대비 플라스틱필름 온실의 생산성을 다소 높이기 위해서는 일출 직후에 내부 환경의 집중적인 관리가 이루어져야 할 것으로 생각된다.

Endophytic Trichoderma gamsii YIM PH30019: a promising biocontrol agent with hyperosmolar, mycoparasitism, and antagonistic activities of induced volatile organic compounds on root-rot pathogenic fungi of Panax notoginseng

  • Chen, Jin-Lian;Sun, Shi-Zhong;Miao, Cui-Ping;Wu, Kai;Chen, You-Wei;Xu, Li-Hua;Guan, Hui-Lin;Zhao, Li-Xing
    • Journal of Ginseng Research
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    • 제40권4호
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    • pp.315-324
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    • 2016
  • Background: Biocontrol agents are regarded as promising and environmental friendly approaches as agrochemicals for phytodiseases that cause serious environmental and health problems. Trichoderma species have been widely used in suppression of soil-borne pathogens. In this study, an endophytic fungus, Trichoderma gamsii YIM PH30019, from healthy Panax notoginseng root was investigated for its biocontrol potential. Methods: In vitro detached healthy roots, and pot and field experiments were used to investigate the pathogenicity and biocontrol efficacy of T. gamsii YIM PH30019 to the host plant. The antagonistic mechanisms against test phytopathogens were analyzed using dual culture, scanning electron microscopy, and volatile organic compounds (VOCs). Tolerance to chemical fertilizers was also tested in a series of concentrations. Results: The results indicated that T. gamsii YIM PH30019 was nonpathogenic to the host, presented appreciable biocontrol efficacy, and could tolerate chemical fertilizer concentrations of up to 20%. T. gamsii YIM PH30019 displayed antagonistic activities against the pathogenic fungi of P. notoginseng via production of VOCs. On the basis of gas chromatography-mass spectrometry, VOCs were identified as dimethyl disulfide, dibenzofuran, methanethiol, ketones, etc., which are effective ingredients for antagonistic activity. T. gamsii YIM PH30019 was able to improve the seedlings' emergence and protect P. notoginseng plants from soil-borne disease in the continuous cropping field tests. Conclusion: The results suggest that the endophytic fungus T. gamsii YIM PH30019 may have a good potential as a biological control agent against notoginseng phytodiseases and can provide a clue to further illuminate the interactions between Trichoderma and phytopathogens.

분말사출성형을 통해 제조된 PH 17-4 STS 강의 소결온도에 따른 인장 특성 (Effect of Sintering Temperature on the Tensile Properties of Powder Injection Molded PH 17-4 STS)

  • 성환진;하태권;안상호;장영원
    • 한국소성가공학회:학술대회논문집
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    • 한국소성가공학회 2001년도 추계학술대회 논문집
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    • pp.305-308
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    • 2001
  • Powder injection molding (PIM) uses the shaping advantage of injection molding but is applicable to metals and ceramics. This process combines a small quantity of polymer with an inorganic powder to form a feedstock that can be molded. After shaping, the polymeric binder is extracted and the powder is sintered often to near-theoretical densities. Accordingly, PIM delivers structural materials in a shaping technology previously restricted to polymers. The process overcomes the shape limitations of traditional powder compaction, the costs of machining, the productivity limits of isostatic pressing and slip casting, and the defect and tolerance limitations of casting. The 17-4 PH stainless steel powders with average diameter of $10{\mu}m$ were injection-molded into flat tensile specimens. Sintering of the compacts was carried out at the various temperatures ranging from 900 to $1350^{\circ}C$. Sintering behavior of the compacts and tensile properties of sintered specimens were investigated.

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포스파젠 고분자를 이용한 Wittig반응에 관한 연구 (Studies on Polyphosphazenes-bound Wittig Reactions)

  • 권석기;전창림
    • 공업화학
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    • 제5권5호
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    • pp.843-850
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    • 1994
  • $[NP(OC_6H_5)_{1.7}(OC_6H_4P(Ph)_2$=$CHCH_2CH_2CH_3)_{0.3}]_n$과 같은 포스파젠 고분자에 부착된 Wittig 시약을 $[NP(OC_6H_5)_{1.7}(OC_6H_4Br)_{0.3}]_n$에 n-butyllithium, diphenylchlorophosphine, 그리고 n-butyl iodide 등으로 처리하여 만들었다. 고분자의 반응들은 [$NP(OC_6H_5)_5(OC_6H_4P(Ph)_2$)]와 같은 고리형 삼중체를 이용한 모델반응 조건들을 고려해 이루어졌다. 포스파젠 고분자에 부착된 Wittig 시약과 benzophenone을 반응시켜 원하는 알켄과 고분자에 부착된 phosphine oxide를 성공적으로 만들었다.

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Hydride 기상증착법을 이용한 InP 성장에서의 배경 불순물 도입에 관한 연구 (Background impurity incorporation in the growth of InP by hydride vapor phase epitaxy technique)

  • Chinho Park
    • 한국결정성장학회지
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    • 제6권2호
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    • pp.141-154
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    • 1996
  • Hydride 기상증착법으로 성장시킨 InP 에피충들을 FTPL 분광법과 변온 Hall 측정법으로 조사하였다. 원료 공급 지역의 온도, 주입되는 HCI과 $PH_{3}$의 몰분율 등 공정변수가 배경 불순물의 주입에 미치는 영향을 조사한 결과, 배경 전하 농도는 원료 공급지역의 온도가 감소 할수록 감소하고 HCl의 주입량이 증가할수록 감소하나 $PH_{3}$의 주입량에는 연구된 몰분율 범위 내에서 상대적으로 무관함을 알 수 있었다. 또한 FTPL spectrum 분석 결과 에피충 내부에 배 경 donor들과 acceptor들이 존재함을 얄 수 있었고 특히, Si donor들, Zn acceptor들, 확인되지 않은 acceptor들이 주된 불순물로 존재함을 알 수 있었다.

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A Roots Method in GI/PH/1 Queueing Model and Its Application

  • Choi, Kyung Hwan;Yoon, Bong Kyoo
    • Industrial Engineering and Management Systems
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    • 제12권3호
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    • pp.281-287
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    • 2013
  • In this paper, we introduce a roots method that uses the roots inside the unit circle of the associated characteristics equation to evaluate the steady-state system-length distribution at three epochs (pre-arrival, arbitrary, and post-departure) and sojourn-time distribution in GI/PH/1 queueing model. It is very important for an air base to inspect airplane oil because low-quality oil leads to drop or breakdown of an airplane. Since airplane oil inspection is composed of several inspection steps, it sometimes causes train congestion and delay of inventory replenishments. We analyzed interarrival time and inspection (service) time of oil supply from the actual data which is given from one of the ROKAF's (Republic of Korea Air Force) bases. We found that interarrival time of oil follows a normal distribution with a small deviation, and the service time follows phase-type distribution, which was first introduced by Neuts to deal with the shortfalls of exponential distributions. Finally, we applied the GI/PH/1 queueing model to the oil train congestion problem and analyzed the distributions of the number of customers (oil trains) in the queue and their mean sojourn-time using the roots method suggested by Chaudhry for the model GI/C-MSP/1.

소아에서 자율신경계의 증상을 동반한 양측 돌발 반두통 1예 (Bilateral paroxysmal hemicrania with autonomic features in a child: A case report)

  • 노영일
    • Clinical and Experimental Pediatrics
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    • 제52권5호
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    • pp.619-621
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    • 2009
  • 돌발 반두통은 일측성이고 짧은 시간동안 심한 통증이 있는 경우이며, 대부분 두개의 자율신경계 증상을 동반한다. 이는 군발 두통의 통증, 동반 증상과 징후와 비슷하지만, 돌발 반두통은 지속시간이 더 짧고, 더 빈번하며, 인도메싸신에 잘 반응한다. 1992년에 Sjaastad에 의해 돌발 반두통이 반대쪽으로도 이동한다고 처음 보고하였으며, 문헌에는 단지 4례가 보고되었다. 4례 중 3례는 자율신경계 증상을 동반하지 않았으며, 1례만 자율신경계 증상 동반을 하였다. 저자는 10세 소아에서 자율신경계 증상을 동반한 전형적인 증상과 인도메싸신으로 치료된 양측 돌발 반두통 1례를 경험하였기에 문헌 고찰과 함께 보고하는 바이다.

LED의 파장 및 광도, 공기주입이 Pavlova lutheri와 Phaeodactylum tricornutum의 최적 성장에 미치는 영향 (Effect of Light-Emitting Diode Wavelength, Light Intensity and Air Flow Ration on Optimal Growth of Pavlova lutheri and Phaeodactylum tricornutum)

  • 최보람;김동수;이태윤
    • KSBB Journal
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    • 제28권3호
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    • pp.170-176
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    • 2013
  • The purpose of this study was to determine optimum condition of Pavlova lutheri and Phaeodactylum tricornutum. Detailed studies were carried out on the effects of various wavelengths of light-emitting diodes (LEDs), light intensities and air flow rations. For the Pa. lutheri, cell growth rates and maximum cell concentrations were similar regardless of wavelengths and air flow rates. Among the different light intensities, cell concentration increased when light intensity of red LED increased. For Ph. tricornutum, red LED was found to be the most effective light source, and light intensity of 3,100 Lux resulted in the most effective for the cultivation of Ph. tricornutum. Different air flow rates were tested to overcome shading effects due to denser cell concentration in the solution. Aeration of 0.8 vvm was determined to be the optimum aeration rate for the cultivation of Ph. tricornutum. Especially, five and two times greater cell concentrations of Pa. lutheri and Ph. tricornutum, respectively, were observed when air was applied.

ChlorophyII and suspended sediment specific absorption coefficient in the sea.

  • Ahn, Yu-Hwan;Moon, Jeong-Eon
    • 대한원격탐사학회:학술대회논문집
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    • 대한원격탐사학회 1998년도 Proceedings of International Symposium on Remote Sensing
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    • pp.399-403
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    • 1998
  • Absorption coefficient per mass unit of particles, specific absorption coefficient, is one of main parameters in developing algorithms for ocean color remote sensing. Specific absorption coefficient of chlorophyll (a$^*_{ph}$) and suspended sediment (SS) were analyzed by "wet filter technique" and "Kishino method" for data sets observed in the Yellow and Mediterranean Seas. A new data-recovering method for the filter technique was also developed using spectrum slopes. This method recovered the baseline of spectrum that was often missed in the Kishino method. High a$^*_{ph}$($\lambda$) values in the oligotrophic Mediterranean Sea and low values in the Yellow Sea were observed, spanning over the range of 0.02 to 0.12 $m^2$/mg, at the chlorophyll maximum absorption wavelength 440nm. The empirical relationship between a$^*_{ph}$ and chlorophyll concentration was found to fit a power function, which was slightly different from that proposed by Bricaud et ai. (1995). Absorption specific coefficients for suspended sediment (a$^*_{SS}$) didn't show any relationship with concentrations of suspended sediment. However, the average value of a$^*_{SS}$ at 440nm was close to the specific absorption coefficient of soil (loess) measured by Ahn (1990). The more-pronounced variability of a$^*_{SS}$ than a$^*_{ph}$ perhaps can explain more wide range of size-distribution for SS, which were determined by their specific gravity and agitation of water mass in the sea surface.

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[1,2-Bis(diphenylphosphino)ethane](nitrato)(trifluoromethylsulfonato)platinum(II)의 합성 및 구조: [Pt(dppe)($NO_3$)($CF_3SO_3$)] (Preparation and Structure of [1,2-Bis(diphenylphosphino)ethane](nitrato)(trifluoromethylsulfonato)platinum(II): [Pt(dppe)($NO_3$)($CF_3SO_3$)])

  • 허현수;이순원
    • 한국결정학회지
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    • 제19권1호
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    • pp.21-24
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    • 2008
  • [[Pt(dppe)$Cl_2]$]와 1 당량 $AgNO_3$ 및 1 당량 AgOTf (OTf=$CF_3SO_3$)의 순차적 반응으로 표제 착물 [Pt(dppe)($NO_3$)($CF_3SO_3$)] (dppe=1,2-bis(diphenylphosphino)ethane, $Ph_2PCH_2CH_2PH_2$)이 합성되었다. Pt 금속은 dppe 리간드의 두 P 원자, nitrato ($NO^-_3$) 리간드의 O 원자, 그리고 triflato (trifluoromethylsulfonato, $OTf^-$) 리간드의 O 원자로 배위되어 있다. Pt 금속의 배위권은 일그러진 평면 사각형으로 기술될 수 있다.