• Journal of the Korean Society of Industry Convergence
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• 제2권1호
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• pp.85-90
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• 1999

The possibility of employment of ceramics, known to be emitting far infrared waves, to keep the growth and the viability of the antagonistic microorganisms was examined. Among four kinds of commercial ceramics, the ceramic powders composed of soft ferrite as a main component has exhibited to grow Pseudomonas cepacia and Saccharomyces cerevisiae better. The ceramic powder in the growth medium has increased the number of cells of P. cepada about ten times and that of S. cerevisiae two to five times more than that in the control at $27^{\circ}C$. The viability of the microorganism at low temperature which was measured from the regrowth behavior at $27^{\circ}C$ after five days store at $4^{\circ}C$ has shown that the lag time of the two microorganisms reduced about three hours without any defect in the rate of logarithmic growth. These results demonstrated that the ceramic powders was available to the growth and viability at low temperature of antagonistic microorganisms.

• KOREAN JOURNAL OF CROP SCIENCE
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• 제65권4호
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• pp.426-435
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• 2020

To determine the damages to waxy corn caused by low temperature weather, we investigated the relationship between the temperature and duration of low temperature treatment and the changes in growth characteristics during the recovery period after the treatments in different growth periods. Growth inhibition started in the low temperature group treated at temperatures below 5℃ for three days. The inhibition ratio (IR) was more than 22% or more in all sample groups. As the treatment duration increased and the Temperature decreased, the growth was more greatly inhibited than that in the control. The IR was the highest at 27% or more in the 2nd leaf stage group treated at below 5℃ for 5 days. The IR was in the order of 2nd leaf stage > 1st leaf stage > coleoptile. The IR during recovery was the highest in the 2nd leaf stage group treated at -3℃ degree for 7 days, nd the values were 82% and 98% for NDVI and Fv/Fm, respectively. Especially, all groups treated at -3℃ showed either no changes or decreases in the growth characteristics. As a result, growth inhibition increased as the temperature decreased, and as the duration of the low temperature increased. The degree of damage was in the order of 2nd leaf stage > 1st leaf stage > coleoptile. All early seedlings stopped growing and withered when exposed to temperatures at or below -3℃ for 3 days or more.

• Korean Journal of Environmental Biology
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• 제30권1호
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• pp.1-8
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• 2012

To understand growth characteristics of eight dominant red tide species ($Prorocentrum$ $minimum$, $Heterocapsa$ $triquetra$, $Scrippsiella$ $trochoidea$, $Akashiwo$ $sanguinea$, $Chattonella$ $marina$, $Heterosigma$ $akashiwo$, $Amphidinium$ $carterae$ and $Rhodomonas$ $salina$) in the Korean coastal water, the growth rates were examined in relation with the impacts of water temperature and bio-volume. Of these, $P.$ $minimum$, $C.$ $marina$, $H.$ $akashiwo$, $A.$ $carterae$ and $R.$ $salina$ were eurythermal species with relatively high growth rates in a borad ranges (15 to $25^{\circ}C$) of water temperature. On the other hand, the growth rate of $H.$ $triquetra$, $S.$ $trochoidea$ and $A.$ $sanguinea$ were high in relatively mid temperature (optimum: $25^{\circ}C$) condition. In particular, $H.$ $triquetra$ was well adapted in low temperature of 5 to $15^{\circ}C$, implying that the species can survive and grows even at very low temperature. Based on results of our experiment, the growth characterestics of five eurythermal species and three mid temperature species may have dominated in Korean coastal water during summer season and fall season, respectively. Contrastively, the growth characteristics of $H.$ $triquetra$ make a consistently dominant during the cold winter season. In addition, the growth rates of large bio-volume species were lower than those of small bio-volume species, indicates that growth of single cells of several flagellates might be depended on the cells sizes.

• Horticultural Science & Technology
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• 제33권3호
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• pp.356-363
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• 2015

This study examined the effects of different day/night temperature regimes or silver ion on growth and flowering of passion fruit 'Tai-nung No.1'. Low temperature treatment ($20/15^{\circ}C$) caused passion fruit cultivar 'Tai-nung No.1' to fail to flower. Flowering induction occurred within a temperature range of $20-30^{\circ}C$, with no significant difference in the days to first flower bud and the total number of flower buds between plants grown at $30/25^{\circ}C$ and $25/20^{\circ}C$. However, plants grown at $30/25^{\circ}C$ exhibited their first flower buds set on the higher nodes and had higher abortion rates of flower buds than those at $25/20^{\circ}C$. Plants grown at $30/25^{\circ}C$ had the most rapid growth and the shortest plastochron. We also evaluated the effect of the ethylene response inhibitors silver nitrate ($AgNO_3$) and silver thiosulfate (STS) on growth and flowering of potted passion fruit 'Tai-nung No.1', when they were exposed to low temperature conditions ($20/15^{\circ}C$) following chemical treatments ($AgNO_3$ or STS, at 0.5 or 1.0 mM). $AgNO_3$ and STS treatments induced flower formation and initial flower bud formation within approximately two weeks at $20/15^{\circ}C$ whereas non-treated control plants exhibited no flower formation. ACC content and activity of ACC oxidase in the leaves of passion fruit 'Tai-nung No.1'exposed to low temperature conditions ($20/15^{\circ}C$) were significantly inhibited by the ethylene inhibitor treatments. These results indicate that ethylene, which is produced under low temperature conditions, plays an important role in inhibiting flower formation in passion fruit.

• Carbon letters
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• 제10권3호
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• pp.230-233
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• 2009

In this study, a low temperature growth of high-quality carbon nanotubes on glass substrate using a local surface heating without heating damage to substrate was tried and characterized. The local joule heating was induced to only Ni/Ti metal film on glass substrate by applying voltage to the film. It was estimated that local surface joule heating method could heat the metal surface locally up to around $1200^{\circ}C$ by voltage control. We could successfully obtain high-quality carbon nanotubes grown at $300^{\circ}C$ by applying 125 V for joule heating as same as carbon nanotubes grown at $900^{\circ}C$.

• Transactions of the Korean Society of Automotive Engineers
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• 제11권5호
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• pp.219-226
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• 2003

The fatigue crack growth behavior of the SA516/60 steel used for pressure vessels was examined experimentally at room temperatures $25^{\circ}C$,$-30^{\circ}C$, $-60^{\circ}C$, $-80^{\circ}C$, $-100^{\circ}C$ and $-120^{\circ}C$ with stress ratio of R=0.05, 0.1 and 0.3. fatigue crack propagation rate da/dN related with stress intensity factor range $\Delta$K was influenced by stress ratio in stable than fatigue crack growth (Region II) with an increase in $\Delta$K. The resistance of fatigue crack growth at low temperature is higher compared with that at room temperature, which is attributed to the extent of plasticity-induced by compressive residual stress according to the cyclic loads. Fractographic examinations reveal that the differences of the fatigue crack growth characteristics between room and low temperatures are explained mainly by the crack closure and the strengthening due to the plasticity near the crack tip and roughness of the crack faces induced.

• Asian-Australasian Journal of Animal Sciences
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• 제23권7호
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• pp.937-945
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• 2010

This study aimed to investigate the effects of dietary zinc (Zn), environmental temperatures and Zn${\times}$temperature interaction on growth, feathering score and mineral composition of broilers. A total of 256 d-old Avian male broiler chicks were randomly allocated to a $4{\times}2$ factorial arrangement with four corn-soybean meal basal diets (containing 44 mg Zn/kg) supplemented with 0, 40, 60 mg/kg Zn (Diets 1, 2 and 3, respectively; 0.8% Ca for these three diets) and non-Zn supplementation, 1.6% Ca (Diet 4) and two temperature conditions (low: 26, 24, $22^{\circ}C$ vs. high: 30, 28, $26^{\circ}C$). All birds were given feathering coverage scores for back, breast, wing, under-wing and tail. The wing and tail were further evaluated for the occurrence and severity of defect feathers. Feathers were then pooled for mineral composition analysis. The results showed that in high temperature conditions, broilers fed Zn-unsupplemented, 0.8% Ca ration (Diet 1) had significantly (p<0.05) lower ADFI and ADG (wk 1-6) than birds under low temperature conditions. However, when the birds were fed 40 and 60 mg/kg Zn supplementation (Diets 2 and 3), the ADFI and ADG in both temperature conditions were not significantly different. In low temperature conditions, the ADFI, ADG (p<0.05), all feather coverage (p<0.01) and tail defect scores (p<0.001) of birds fed Diet 4 (excess Ca) were significantly poorer than those fed Diet 1. More Ca (p<0.05) was retained in the feathers of broilers fed Diet 4 under high temperature conditions. Broilers fed the Zn-unsupplemented ration (Diet 1) had significantly higher feather phosphorus (p<0.01) and potassium (p<0.05) concentrations than those fed the 60 mg/kg Zn-supplemented ration (Diet 3). A reduction of feather phosphorus (p<0.01) and potassium (p<0.05) and higher manganese (p<0.05) concentrations were observed in Diet 4 broilers as compared to those fed Diet 1. Under high temperature conditions, broilers had lower iron (p<0.05) and higher manganese (p<0.05) concentrations in feathers. Broilers kept in high temperature conditions had a higher Zn requirement and 40 mg/kg Zn supplementation was sufficient for the birds to achieve optimum growth. Supplemental Zn ameliorated the adverse effect of high temperature on growth and occurrence of tail feather defects. Excess Ca disrupted Zn metabolism to exert a detrimental effect on growth performance and normal feathering and this was elucidated in the birds kept in low temperature conditions.

• Korean Journal of Fisheries and Aquatic Sciences
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• 제44권3호
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• pp.276-283
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• 2011

The growth and tolerance for water temperature and salinity were compared among red sea bream Pagrus major (RSB) black sea bream Acanthopagrus schregeli (BSB) and their hybrid ($F_1$), female RSB ${\times}$ male BSB. The growth of the $F_1$ fish did not differ until 27 days after hatching (dAH), after which the most rapid growth was observed until approximately 300 dAH, followed by RSB and BSB. However, the RSB had out grown the $F_1$ fish by approximately 303 dAH. By 480 dAH, the RSB were largest, followed by the $F_1$ and BSB groups. The tolerances for high and low water temperature were significantly different for each species and growth stage. The largest tolerance spectrum was observed in the BSB group, and the tolerance spectrums gradually decreased with increasing final body weight. During the salinity tolerance trials, all of the species started to die following transfer into freshwater (0 psu). BSB showed the highest survival rate when kept in fresh water for an average of 29.9 hours, while the $F_1$ fish were more tolerant than the RSB fish. The fish were increasingly tolerant to fresh water and changes in water temperature as they grew, while the size of the temperature spectrum remained unchanged but shifted to a lower temperature range with growth. Our results demonstrate that $F_1$ performed well in terms of growth compared to parental fish, with higher temperature and salinity tolerances than RSB, and is thus suggested to be a suitable aquaculture species for Korea and northeast China.

• Bulletin of the Korean Chemical Society
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• 제31권10호
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• pp.2819-2822
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• 2010

Forest of single-walled carbon nanotubes (SWNTs) was grown at $450^{\circ}C$ by water-plasma chemical vapor deposition using ultrathin iron on alumina supporting film. The growth rate of the SWNT forest is ${\sim}0.9\;{\mu}m/min$, and the diameters of nanotubes are mainly in a range of 3.0 ~ 3.5 nm. The low intensity ratio of D- to G-band ($I_D/I_G$ ~ 0.098) in Raman spectra indicates that our SWNT forest grown at $450^{\circ}C$ is fairly pure and crystalline. This low temperature growth of SWNT forest may enable variable applications requiring the vertically-aligned nanotubes to obtain large surface area.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 한국전기전자재료학회 1994년도 추계학술대회 논문집
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• pp.54-58
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• 1994

H$_2$ bake and GeH$_4$ clean are used as a in-situ pre-clean method in low temperature Si based epitaxial growth technology using rapid thermal processing chemical vapor deposition (RTPCVD). In this paper, the H$_2$ bake and GeH$_4$ clean processes are optimized for low surface defect density using Taguchi method. In H$_2$ bake process, the epitaxial growth temperature affects dominantly on the surface defect density, and the next affecting factors are H$_2$ bake temperature and rinse time in de-ionised water. In GeH$_4$ clean process, GeH$_4$ clean temperature affects most strongly on the surface defect density, and the minor factor is GeH$_4$flow rate. The optimum process conditions predicted fly Taguchi method agree well with tile experimental data in both in-situ clean processes.