• Title/Summary/Keyword: growth reduction

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Effect of substrate pretreatment on the growth yield enhancement and growth temperature decrease of carbon nanotubes (탄소나노튜브의 합성수율 증대와 저온 합성에 미치는 기판 전처리의 영향)

  • Shin, Eui-Chul;Jo, Sung-Il;Jeong, Goo-Hwan
    • Journal of Industrial Technology
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    • v.39 no.1
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    • pp.7-14
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    • 2019
  • Carbon nanotubes (CNT) on metal substrates are definitely beneficial because they can maintain robust mechanical stability and high conductivity between CNT and metal interfaces. Here, we report direct growth of CNT on Ni-based superalloy, Inconel 600, using thermal chemical vapor deposition (CVD) with acetylene feedstock in the growth temperature range of $400-725^{\circ}C$. Furthermore, we studied the effect of substrate pretreatment on the growth yield enhancement and growth temperature decrease of CNT on Inconel 600. Activation energy (AE) for CNT growth was estimated from the CNT height change with respect to the growth temperature. The AE values significantly decreased from 205.03 to 24.35 kJ/mol by the pretreatment of thermal oxidation of Inconel substrate at $725^{\circ}C$ under ambient. Higher oxidation temperature tends to have lower activation energy. The results have shown the importance of pretreatment temperature on CNT growth yield and growth temperature decrease.

Analysis of the Impact of Initial Carbon Emission Permits Allocation on Economic Growth (초기 탄소배출권 배분이 경제성장에 미치는 영향 분석)

  • Park, Sunyoung;Kim, Dong Koo
    • Environmental and Resource Economics Review
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    • v.20 no.2
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    • pp.167-198
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    • 2011
  • The Korean government recently announced greenhouse gases (GHG) emissions reduction target as 30% of 2020 business as usual (BAU) emission projection. As carbon emissions trading is widely used to achieve reductions in the emissions of pollutants, this study deals with the sectoral allocation of initial carbon emission permits in Korea. This research tests the effectiveness of a variety of allocation rules based on the bankruptcy problem in cooperative game theory and hybrid input-output tables which combines environmental statistics with input-output tables. The impact of initial emission permits allocation on economic growth is also analyzed through green growth accounting. According to the analysis result, annual GDP growth rate of Korea is expected to be 4.03%, 4.23%, and 3.67% under Proportional, Constrained Equal Awards, and Constrained Equal Losses rules, respectively. These rates are approximately from 0.69% points to 0.13% points lower than the growth rate of 4.36% without compulsory $CO_2$ reduction. Thus, CEA rule is the most favorable in terms of GDP growth. This study confirms the importance of industry level study on the carbon reduction plan and initial carbon emission permits should reflect the characteristic of each industry.

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An Application of Toxicity Test to Water Management and Water Treatment (수질관리와 수처리에의 독성시험의 응용)

  • Kim, Berm-Soo
    • Journal of Korean Society of Water and Wastewater
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    • v.19 no.5
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    • pp.639-646
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    • 2005
  • In this research, we tried to develop the application method to water management and treatment using toxicity test method. When we measure the toxicity of environmental samples, we have to decide whether we take some countermeasures to reduce the toxicity or not. The first issue is how to set these action levels in each bioassays. A new idea was attempted to authorize indirect approach of each bioassays through the response characteristics against mixture of chemicals in water quality standard. The significant response in the cell-growth-inhibition bioassay was detected for standards-mixture(STDs). For acute toxicity assay, STDs-based implicit correlation between risks to humans and bioassay data showed a rational approach to set action levels in practical management. A simple model was proposed to describe and predict the changes in the total toxicity based on the concentrations of toxic-controlling chemicals during the ozonation of landfill leachates. On the basis of this simple model, toxicity reduction was predicted for pre-aggregation treatment before ozonation and ozone concentration during the ozonation. The method proposed in this study would be useful in optimizing water treatment processes and their running conditions in terms of the toxicity reduction efficacy.

Effects of Phytohormone and Activated Carbon on the Growth and Rooting of Teratoma Shoot Induced from Crown Gall Callus in Nicotiana tabacum cv. NC 2326 (연초 Crown Gall Callus유래 Teratoma Shoot의 생육과 발근에 미치는 식물호르몬과 활성탄의 영향)

  • Yang, Deok-Chun;Kang, C.K.;Choi, K.T.
    • Journal of the Korean Society of Tobacco Science
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    • v.14 no.1
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    • pp.33-41
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    • 1992
  • These studies were conducted to investigate effects of phytohormone and activated carbon on the growth and rooting of teratoma shoots induced from Nicotiana tabacum cv. NC2326 transformed by Aerobacterium tumefaciens C58. GA was effective for shoot elongation and reduction of multiple shoots from teratoma shoot, however, leaves of teratoma shoot cultured on the medium with GA were pointed. ABA was also effective in promoting shoot elongation, but was not for reduction of multiple shoots. Teratoma shoot cultured on the medium with 1 n activated carbon promoted shoot elongation and inhibited the number of shoots differentiated, but was grown as abnormal shoot. Addition of 1% activated carbon and 0.5mg/l BA to culture media was effective for shoot elongation and reduction of multiple shoot and for formation of round leaves as normal leaves. Though these shoots were inoculated on the rooting medium, they could not from roots but formed multiple shoots. Boric acid, myo-inositol and sucrose were also ineffective on the rooting of teratoma shoots.

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Effects of Austenitization Temperature and Hot Deformation on Microstructure of Microalloyed Low Carbon Steels (저탄소 미량합금강의 미세조직에 미치는 고온변형의 효과)

  • Kim, Sea-Arm;Lee, Sang Woo
    • Journal of the Korean Society for Heat Treatment
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    • v.16 no.2
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    • pp.83-89
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    • 2003
  • As a research for developing fine-grained high strength low carbon steels, the effects of austenitization temperature and hot deformation on microstructure was investigated in 0.15 wt.% carbon steels with microalloying elements such as Nb and Ti. When the steels were reheated at $1250^{\circ}C$, Nb containing steel showed very coarse austenite grain size of $200{\mu}m$ whereas Nb-Ti steel did fine one of $70{\mu}m$ because Ti carbonitrides could suppress the austenite grain growth. In case of 50% reduction at $850^{\circ}C$, the austenite grains in the Nb steel partially recrystallized while those in the Nb-Ti steel fully recrystallized probably due to finer prior austenite grains.For the Nb-Ti steel, ferrite grain size was not sensitively changed with austenitization temperature and compression strain and, severe deformation of 80% reduction was not essentially necessary to refine ferrite grains to about $3{\mu}m$ which could be obtained through lighter deformation of 40% reduction.

Two Part Triplane Fracture with Extention through Medial Malleolus (Four Cases Report) (족관절 내과를 침범한 두 부분 삼면 골절(4예 보고))

  • Cha, Seung-Do;Kim, Hyung-Soo;Chung, Soo-Tae;Yoo, Jeong-Hyun;Park, Jai-Hyung;Kim, Joo-Hak;Kim, Yong-Hoon
    • Journal of Korean Foot and Ankle Society
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    • v.13 no.2
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    • pp.179-183
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    • 2009
  • The triplane fracture has been described as a fracture of the distal tibial epiphysis occurring across three planes-sagittal, transverse and coronal. The characteristic pattern of fusion of distal tibial epiphysis explains the special configuration of the fragments in the triplane fracture. According to Dias-Tachdjian classification, triplane fracture is classified two part fracture, three part fracture, four part fracture and two part fracture with extension to the medial malleolus. Among four types, two part triplane fracture with extension to the medial malleolus is a relatively rare injury and generally is not treated by closed reduction. Such fractures should have an anatomic reduction and adequate fixation to restore the joint congruity and obtain an anatomic reduction of the growth plate to prevent a future growth deformity. This is usually best accomplished with an open reduction and screw fixation or k-wire fixation. We experienced two part triplane fracture with extension to medial malleolus and check the CT to define the extent of the injury completely. And then we underwent open reduction and screw fixation for the fracture. As a result, we present four cases of two part triplane fracture with extension with review of related literatures.

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Reduction Efficiency of the Stormwater Wetland from Animal Feeding-Lot (강우유출수 처리목적 인공습지의 강우시 오염물질 저감특성에 관한 연구)

  • Park, Kisoo;Niu, Siping;Kim, Youngchul
    • Journal of Wetlands Research
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    • v.15 no.1
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    • pp.79-90
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    • 2013
  • Stormwater wetland targeted to treat the rainfall runoff from cow feeding-lot basin has been monitored from May 2010 to November 2011. Reduction efficiency estimated based on 20 rainfall event monitoring was 88%, 54%, 70%, 31%, and 64% for TSS, BOD, $COD_{Cr}$, TN, and TP, respectively. Theoretically, as rainfall depth increases, hydraulic exchange ratio has to be increased. When the exchange ratio approaches to 1 (usually design goal), TSS reduction efficiency was estimated about 55%. Uncertainty in reduction efficiency of the stormwater wetland is normally very high due to the continuous rainfall activity, its magnitude and intensity, antecedent dry days, and other natural variables which can not be controlled by experiment conductors. In this study, predominant affecting variables was found to be hydraulics caused by consecutive rainfall events having different intensity and algal growth during dry days.

Vertical Shoot Growth of Korean Lawngrass (Zoysia japonica Steud.) Influenced by Trinexapac-ethyl, Amidochlor, and Mefluidide (Trinexapac-ethyl, Amidochlor 및 Mefluidide가 들잔디 직립생장에 미치는 효과)

  • Kim, Kyoung-Nam;Kim, Yong-Seon
    • Horticultural Science & Technology
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    • v.17 no.5
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    • pp.572-577
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    • 1999
  • Research was initiated to evaluate plant growth regulator effects on the vertical shoot growth of Korean lawngrass and to determine desirable growth regulator and its rate. The experiments were conducted twice at different sites in 1995. All the tested growth regulators inhibited the growth, but the inhibition period was variable among the product in Experiments I and II. During the first week after treatment, there was approximately 10 to 20% growth reduction in most of the treated plots. In the amidochlor-treated plots, growth suppression was effective for 3 to 4 weeks at low to medium rates ($0.60mL{\cdot}m^{-2}$). A Type II growth regulator, trinexapac-ethyl exceeding the medium rate of $0.08mL{\cdot}m^{-2}$ consistently tended to suppress vertical shoot growth for 8 weeks, being above 35% reduction in both experiments. In the plots applied with mefluidide, growth suppression appeared with foliar discoloration 3 or 4 days earlier than the other growth regulators and continued to work till the 8 weeks after treatment. Suppression intensity on vertical shoot growth increased with time after treatment up to a certain period of time, depending on growth regulators. Generally, the higher the application rate, the greater the suppression intensity. Seasonal variation of activity and effectiveness of growth regulators was observed, resulting in lower suppression intensity in July than in June. It is expected to reduce mowing requirements by 30 to up to 60% for a certain period with a specific growth regulator. In low to medium maintenance of Korean lawngrass turf, a long-term suppression may be more effectively accomplished with trinexapac-ethyl rather than mefluidide and amidochlor in terms of vertical shoot growth inhibition. Therefore, turf managers will need to select proper growth regulator and determine optimum rate of application for turfgrass management, based on a defined period of mowing reduction.

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Bacillus vallismortis EXTN-1-Mediated Growth Promotion and Disease Suppression in Rice

  • Park Kyung-Seok;Paul Diby;Yeh Wan-Hae
    • The Plant Pathology Journal
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    • v.22 no.3
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    • pp.278-282
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    • 2006
  • Bacillus vallismortis EXTN-1, a biocontrol agent in cucumber, tomato and potato was tested in rice pathosystem against rice fungal pathogens viz. Magnaporthe grisea, Rhizoctonia solani and Cochliobolus miyabeanus. Apart from increasing the yield in the bacterized plants (11.6-12.6% over control), the study showed that EXTN1 is effective in bringing about disease suppression against all the tested fungal pathogens. EXTN-l treatment resulted in 52.11% reduction in rice blast, 83.02% reduction in sheath blight and 11.54% decrease in brown spot symptoms. As the strain is proven as an inducer for systemic resistance based on PR gene expression in Arabidopsis and tobacco models, it is supposed that a similar mechanism works in rice, bringing about disease suppression. The strain could be used as a potent biocontrol and growth-promoting agent in rice cropping system.

Influence of Ni Addition on Mechanical and Magnetic Properties of Yttria-Stabilized Tetragonal Zirconia

  • Kondo, H.;Sekino, T.;Choa, Y.H.;Kusunose, T.;Nakayama, T.;Niihara, K.
    • Proceedings of the Korea Association of Crystal Growth Conference
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    • 2000.06a
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    • pp.243-248
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    • 2000
  • Effect of NiO addition on microstructure, stability of tetragonal phase and mechanical properties was investigated. (Y, Ni)-TZP solid solution was obtained by pressureless sintering. The fracture toughness was increased by solid solution of NiO. Neither reaction phase nor glassy phase was observed at the grain boundaries. From these results, it was determined that solid solution of NiO was destabilized tetragonal phase of Y-TZP. Y-TZP/Ni nanocomposite that contained nano-sized Ni particles was also fabricated by internal reduction method. Some evaluations and discussions were carried out for both (Y, Ni)-TZP solid solution and Y-TZP/Ni nanocomposite.

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