• Korean Journal of Plant Resources
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• v.32 no.4
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• pp.312-317
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• 2019

This study was conducted with the purpose of examining the suitability of Euphorbia jolkinii Boiss. as cut flower, so that it may be introduced as a new ornamental crop. For this purpose, effect of various holding solutions on vase solution uptake rate, vase life, and relative fresh weight of cut flowering branches of E. jolkinii was examined. After harvest, cut branches were treated with 10, 50, and $100mg{\cdot}L^{-1}$ of 8-hydroxyquinoline sulfate (8-HQS), 0.1 and 0.2 mM of silver thiosulfate (STS), Chrysal, and Floralife. The cut branches of E. jolkinii were placed under the environmental conditions maintained at air temperature of $22.6^{\circ}C$, relative humidity of 45%, and 9/15h photoperiod that was controlled using fluorescent lamps (light intensity of $9.89{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$). A holding solution containing $10mg{\cdot}L^{-1}$ 8-HQS was found to be significantly effective for vase solution uptake rate compared to control, $50mg{\cdot}L^{-1}$ 8-HQS, and $100mg{\cdot}L^{-1}$ 8-HQS treatments. However, no significant difference was found in vase life between the branches treated with $10mg{\cdot}L^{-1}$ 8-HQS holding solution and branches of the control group. Increasing holding solution concentrations of STS was found to have negative effect on the vase life of cut E. jolkinii branches. Relative fresh weight of cut E. jolkinii branches were significantly decreased by two commercial holding solutions, Chrysal and Floralife. It is expected that these results would aid further studies on utilization of E. jolkinii as cut flower crop.

• Microbiology and Biotechnology Letters
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• v.47 no.3
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• pp.381-389
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• 2019

Chlorella vulgaris was isolated from the Nile River, Qalubia Governorate, Egypt, for possible use in biodiesel production. BG-II nutrient growth media was used for isolation and laboratory growth. Identification was performed via 18S rRNA gene amplification, followed by sequencing. The alga was exposed to UV-C (254 nm) for 15, 30, and 45 s to improve dry weight accumulation and to increase the oil production. Daily measurements of dry weight ($g{\cdot}l^{-1}$) were performed; oil content and volumetric lipid productivity were also determined. UV-C exposure led to an increase in the volumetric lipid productivity by 27, 27.3, and $32.4mg{\cdot}l^{-1}{\cdot}d^{-1}$ with 15, 30, and 45 s, respectively, as compared with the control, which resulted in $18mg{\cdot}l^{-1}{\cdot}d^{-1}$. Of the examined mutants, the one with the highest productivity was re-irradiated by UV-C (254 nm) for 15, 30, 45, and 60 s. For 15 s of exposure time, the oil content increased to 34%, while it was 31% at 30 s; further, it decreased to 22% at 45 and 60 s exposures. The fatty acid methyl ester profile was 82.22% in the first mutant at 45 s, compared with the wild strain that contained a total of 66.01% of FAs. Furthermore, the highest levels of polyunsaturated fatty acid methyl ester were observed in the mutant exposed for 45 s, and it reached 11.41%, which reduced the cetane number to 71.3.

• Journal of Bio-Environment Control
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• v.18 no.3
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• pp.291-296
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• 2009

This study was conducted to compare the storability of 6 chicory cultivars for producing chicon; 'Vintor', 'Focus', 'Metafora', 'Kibora', 'Nobus', and 'Redoria Red' grown in 2 regions: Chuncheon (plain region) and Pyeongchang (high land region). Chicons were produced from chicory roots that grown for 120days and then stored for over 120days at $2^{\circ}C$ and 90% of RH conditions. To produce chicon, chicory root was forced at $18^{\circ}C$ for 22days with suppling the nutrient solution ($KNO_30.54g{\cdot}L^{-1}$, $Ca(NO_3)_2\;1.02g{\cdot}L^{-1}$, $MgSO_4\;0.36g{\cdot}L^{-1}$, $KH_2PO_4\;0.21g{\cdot}L^{-1}$, $K_2SO_4\;0.10g{\cdot}L^{-1}$, pH 7.0). Chicons produced from 6 different chicory cultivars packed with $25{\mu}m$ ceramic film and stored for 25days at $8^{\circ}C$. The fresh weight of chicon in MAP was maintained to 99.5% of pre-storage weight. The fresh weight of 'Redoria Red' was lowest in all cultivars, and that of Chuncheon region cultivated treatment was lower than Pyeongchang treatment. The $CO_2$ and $O_2$ concentration in chicon MAP were 2% and $10{\sim}17%$. There were not significantly different among cultivars and between regions, although 'Redoria Red' cultivar showed highest $CO_2$ and lowest $O_2$ concentrations. The ethylene concentration in chicon MAP was $1.0{\mu}{\iota}{\cdot}{\iota}^{-1}$ and also didn't show any significant difference among all treatments. Chicon detoriorated visual quality with appearing russet spotting that result from ethylene gas. The visual quality of 'Redoria Red' cultivar decreased faster than the other cultivars. 'Metafora', 'Focus', and 'Kibora' maintained higher firmness of their leaf than the others, and the firmness was higher grown in Pyeongchang region cultivated treatments than in Chuncheon region.

• Applied Chemistry for Engineering
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• v.9 no.4
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• pp.529-535
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• 1998

This study was made to investigate the effect of variation in pulping process conditions such as wastepaper blending treatments, temperature, and chemical blending treatments on the deinked pulp. Design of experiments was used to select the major factors which significantly influenced on the deinked pulp. As one of the statistical analysis technique, analysis of variance and multiple comparison technique was used to find the best process condition and the predicted values and confidence intervals for brightness and strength were obtained. In the condition of $Na_2SiO_3$ 2.0%, $H_2O_2$ 0.5% and wastepaper blending treatments (KONP : AONP : OMG = 40 : 30 : 30 wt %) the highest brightness of 50.5% was predicted with 90% confidence interval (49.0, 52.0). On a concentration of $H_2O_2$ 0.5%, the highest tensile index of $35.7N{\cdot}m/g$ was predicted with 90% confidence interval (34.6, 36.6) at the pulping temperature of $50^{\circ}C$. On a concentration of surfactant 0.1%, the highest burst index of $0.129kPa{\cdot}m^2/g$ was predicted with 90% confidence interval (0.125, 0.133) at the pulping temperature of $50^{\circ}C$.

• Journal of Korean Society of Environmental Engineers
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• v.28 no.5
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• pp.563-572
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• 2006

In order to propose optimum in-situ treatment for reducing phosphorous release from sediment of stationary lakes, a series of column tests were performed. The sediment used in experiment was very fine clay with a mean grain site $7.7{\phi}$ and high $C_{org}$ contents(2.4%). Phosphorous releases were evaluated in two ways : in lake water(with microbial effect) and in distilled water(without microbial effect). As in-situ capping material, sand and loess were used while Fe-Gypsum and $SiO_2$-Gypsum were used for in-situ chemical treatment. In case of lake water considering the effect of microorganism, phosphorous concentration rapidly decreased in the early stage of experiment but it was gradually increased after 10 days. Flux of phosphorous release for control was $3.0mg/m^2{\cdot}d$. Whereas, those for sand layer capping(5 cm) and loess layer capping(5 cm) were $2.5mg/m^2{\cdot}d\;and\;1.8mg/m^2{\cdot}d$, respectively because the latter two were not consolidated sufficiently. For Fe-gypsum and $SiO_2$-gypsum the fluxes were $1.4mg/m^2{\cdot}d$ which meant that reduction efficiency of phosphorous release was more than 40% higher than that of control. The case capping with complex layer was $1.0mg/m^2{\cdot}d$, which showed high reduction efficiency over 60%. The addition of gypsum($CaSO_4{\cdot}2H_2O$) into the sediment reduced release of Phosphorus from the sediments. Gypsum acted as a slow-releasing source of sulphate in sediment, which enhanced the activity of SRB(sulfate reducing bacteria) and improved the overall mineralization rate of organic matter.

• Analytical Science and Technology
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• v.6 no.2
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• pp.225-229
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• 1993

ATZ was prepared by adding an alumina sol equivalent to 2wt% as $Al_2O_3$ to an aqueous slurry of alumina (AKP-30) and zirconia (TZ-2Y or TZ-0Y) in the range of 10-30ATZ, followed by gelation, calcination, and sintereing between $1450^{\circ}C{\sim}1550^{\circ}C$ for 2h. They showed excellent microstructure with alumina grains of <$0.5{\mu}m$ and>99% of the theoretical density. Fracture toughness of ${\sim}8MPa{\cdot}m^{1/2}$ was observed around 20ATZ which was higher than $6MPa{\cdot}m^{1/2}$ obtainable by ball-milling.

• Bulletin of the Korean Chemical Society
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• v.8 no.1
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• pp.1-3
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• 1987

The crystal structure of $K_5Na_2[SbW_6O_{24}]{\cdot}12H_2O$ has been determined. Final R = 0.081 for 890 observed independent reflections collected by diffractometry. Crystal data as follows; trigonal, space group R3m, a = 9.794(1) ${\AA},\;{\alpha}$ = 84.72$(1)^{\circ}$, Z = 1. The heteropolyanion has a structure with point symmetry $D_{3d}$ (3m), of the ideal Anderson-type heteropolyanion. The Sb-W and W-W distances are 3.259(2) and 3.259(3) ${\AA}$. Three types of W-O ($W-O_t,\;W-O_b\;and\;W-O_c$) distances are 1.73(2), 1.95(4) and 2.20(3) ${\AA}$. The Sb-O distance is 1.97(3) ${\AA}$.

• Proceedings of the KIEE Conference
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• 2007.07a
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• pp.242-243
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• 2007

Highly transparent conducting aluminum-doped zinc oxide (AZO) thin films were deposited on Corning glass substrate using an Nd:YAG pulsed laser deposition technology. AZO thin films deposited with 650nm thickness showed the best electrical properties of the electrical resistivity of $4.6{\times}10^{-4}[{\Omega}{\cdot}cm]$, a carrier concentration of $9.3{\times}10^{20}[cm^{-3}]$, and a carrier mobility of $31[cm^2/V{\cdot}s]$. Besides, the optical transmittance spectra in visible region (200-800nm) of AZO thin films show an high average transmittance over 90%.

• Resources Recycling
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• v.17 no.6
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• pp.10-16
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• 2008

In this study, the crystallization of cerium carbonate from cerium chloride solution by addition of ammonium bicarbonate was investigated. The concentration of reactants such as cerium chloride(0.5-2M) and ammonium bicarbonate, and reaction temperature($20-60^{\circ}C$) have a great effect on the crystal types of cerium carbonate such as lanthanite-type cerium carbonate[$Ce_2(CO_3)_3{\cdot}8H_2O$] and tengerite-type cerium carbonate[$Ce_2(CO_3)_3{\cdot}2.5H_2O$]. The crystallinity of cerium carbonate changed from lanthanite to tengerite as the concentration of reactants and reaction temperature increased. Transformation of cerium carbonate hydrate was transformed to cerium hydroxy carbonate depended on the drying conditions. Cerium carbonate of lanthanite and tengerite has the shape of aggregates with plate type crystal, and the size of lanthanite and tengerite crystal was $3{\mu}m$ and $5{\mu}m$, respectively. Cerium hydroxy carbonate has the shape of aggregates with needle type crystal, and the crystal size was about $7{\mu}m$.

• Journal of Korean Society of Environmental Engineers
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• v.28 no.11
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• pp.1154-1161
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• 2006

Air drying equipment was built as a device for reduction of dewatered cake from wastewater and waterworks sludge and to reproduce it by reusable matter. Dewatered cake was supplied into the air drying equipment which operated by air velocity of 80 m/sec, air rate 30 $m^3/min$ and air temperature of $40^{\circ}C$, and dried to produce the dried powder. The air drying equipment was composed of the air ejector which made high-speed fluid field, and cyclone which made circling fluid field. Dewatered cake was crushed at the high-speed zone as first step, and formed into dried powder of sphere shape by the collision between particles at the circling fluid zone.. Wastewater sludge with water content of 82.5 wt% was supplied 1.0 kg/min into air drying equipment and produced the dried powder which had the water content of 62.3 wt% and mass median diameter of 2.4 mm after process. At that time, it was analyzed that water removal rate was 0.1 $H_2O{\Delta}kg/min{\cdot}DS$ kg and air consumption was 170 $m^3/DS$ kg. Under same experimental conditions, when waterworks sludge was dried, water content of dried powder decrease to 47.5 wt% and mass median diameter decrease 2.1 mm and water removal rate increase 0.13 $H_2O{\Delta}kg/min{\cdot}DS$ kg. Air consumption increase 180 $m^3/DS$ kg with comparison to the results of wastewater sludge. Therefore, this technology was evaluated that drying the dewatered cake of waterworks sludge was more efficient than wastewater sludge, and also economical sludge handling technology due to drying the cake by only air.