• Korean Journal of Weed Science
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• v.7 no.3
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• pp.257-264
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• 1987

Effect of various physical and chemical treatments on dark germination of Oenothera lamarckiana seeds were primarily investigated to find out factors affecting germination. Germination of seeds which did not germinate in the constant temperature and darkness was induced by several physical treatments such as sonification, wetting and drying, freezing and thawing, and removal of seed coat. Pretreatment of chilling ($4^{\circ}C$), freezing ($-10^{\circ}C$) and incubation at high temperature ($80^{\circ}C$) induced dark germination of seeds which did not germinate in the constant temperature ranges of 15 to $40^{\circ}C$ under darkness. Alternating temperature also had a stimulatory effect on dark germination of Oenothera lamarckiana seeds. Sensing of seeds to alternating temperature appeared to be completed during the first two days after imbibition. The minimum difference of temperature required for dark germination was $5^{\circ}C$ in the range of $15-25^{\circ}C$. A thiourea (1.0%) treatment induced dark germination, but GA, IAA, BA and Ethrel failed to do so.

• Journal of the Korean Wood Science and Technology
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• v.39 no.6
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• pp.490-497
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• 2011

In this study, we determined optimal conditions for simultaneous saccharification and fermentation (SSF) using corncob biomass pretreated with oxalic acid. The effect of SSF temperature ($25.8{\sim}34.2^{\circ}C$) and agitation speed (80~220 rpm) were significant at a 99% confidence level in its effect on ethanol production. The highest ethanol production was expected when SSF was performed at $30^{\circ}C$, 170 rpm (22.5 g/L). The ethanol production was improved by mixture of yeast extract (1.25 g/L) and urea (1.25 g/L) as nitrogen source. However, addition of trace metal components and vitamin for SSF was not affected in the ethanol production. Optimal concentration of $KH_2PO_4$, $MgSO_4{\cdot}7H_2O$ for SSF was 1 g/L, 0.25 g/L respectively.

• Korean Journal of Medicinal Crop Science
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• v.5 no.1
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• pp.14-20
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• 1997

To increase the efficiency of the callus induction in anther culture of Schizandra chinensis, the effects of culture stage, low temperature pretreatment, growth regulators, sucrose and gelling agents were tested on Murashige and Skoog's medium. And the effects of ABA and $AgNO_3$ on organogenesis were investigated. The most suitable stage for anther culture was at the middle to late uninucleate stage, of which the flower size was $6.2{\pm}0.6{\times}4.0{\pm}0.4mm(Length{\times}width)$, and the frequency of callus induction was 13.3%. The effect of low-temperature pretreatment on callus induction was highest as 12.5% in the trearment for 8 days at $4^{\circ}C$. The combination of 1.0 mg/L 2, 4-D and 0.25 mg/L kinetin for callus induction was most effective as 8.3% among various media. The frequency of callus induction was excellent as 10.8% in 4% sucrose. Effect of gelling agents on callus induction was highest as 9.0% on 0.6% Gelrite medium. The prevention of callus browning was effective on the media supplemented with ABA and $AgNO_3$ and rooting was promoted on medium supplemented with 5 mg/L ABA. But shoot was not developed.

• Food Science and Preservation
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• v.18 no.4
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• pp.475-480
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• 2011

This papers were studies the effects of high $CO_2$ concentration pretreatment and ascorbic acid on the browning of fresh-cut apples. The prepared samples were dipped in 1% (w/v) ascorbic acid solution (AA). Fresh-cut apples (3 pieces) were packed in polypropylene bags (0.03 mm, $20{\times}15$ cm), and stored at $10^{\circ}C$ for 16 days. AA-treated samples showed higher L value than those of non-treated and control (dipped in water without $CO_2$ pretreatment), while non-treated samples showed higher hardness than AA-treated sample. Total soluble solids, pH, titratable acidity were not affected by high $CO_2$ pretreatment and AA treatment. These result shows high $CO_2$ concentration pretreatment with dipping in 1% ascorbic acid solution (AA) has an effects on controlling enzymatic browning during the storage of fresh-cut 'Fuji' apples.

• KSBB Journal
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• v.22 no.4
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• pp.244-248
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• 2007

The treatment of a model wastewater containing high concentration, 10 $g/{\ell}$, of phenol in an integrated wet oxidation-aerobic biological treatment was investigated. Partial wet oxidation under mild operating conditions was capable of converting the original phenol to biodegradable organic acids such as maleic acid, formic acid and acetic acid, the solution of which was subjected to the subsequent aerobic biological treatment. The wet oxidation was carried out at 150$^{\circ}C$ and 200$^{\circ}C$ and the initial pH of 1 to 12. The high temperature of 200$^{\circ}C$ and the acidic initial condition in the wet oxidation led to effluents of which biodegradability was higher in the subsequent biological oxidation process, as assessed by chemical oxygen demand (COD) removal. Homogeneous catalyst of $CuSO_4$ was also used for increasing the oxidation rate in the wet oxidation at 150$^{\circ}C$ and initial pH of 3.0. However, the pretreatment with the catalytic wet oxidation resulted in effluents which were less biodegradable in the aerobic biological process compared to those out of the non-catalytic wet oxidation at the same operating conditions.

• Horticultural Science & Technology
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• v.29 no.5
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• pp.494-499
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• 2011

Cold pretreatment, washing medium and composition of nutrient media may have marked effects on microspore embryogenesis. When microspores isolated from radish (Raphanus sativus L. cv. Gwanhun) flower buds were washed with Nitsch & Nitsch (NLN) medium liquid medium containing $130g{\cdot}L^{-1}$ sucrose (NLN-13), yields of microspore-derived embryos were greater than when using B5 liquid medium containing $130g{\cdot}L^{-1}$ sucrose. Microspore viability is known to decrease rapidly with storage; however, in this experiment, microspore viability was maintained for 24 h at $4^{\circ}C$ without media. Among the various medium concentrations used ($0.25{\times}$, $0.5{\times}$, $1.0{\times}$, $2.0{\times}$, and $4.0{\times}$ NLN liquid medium), $0.5{\times}$ NLN liquid medium induced the most efficient formation of microspore-derived embryos. In addition, microspore-derived embryos yields were greater when microspores were cultured in $0.5{\times}$ NLN liquid medium supplemented with $0.25{\times}$, $0.5{\times}$, and $1.0{\times}$ NLN microelements, compared to medium not supplemented with microelements. In this study, the highest yield of microspore-derived embryos was observed when the microspores derived from flower buds were washed using NLN-13 liquid medium and then cultured on $0.5{\times}$ NLN liquid medium supplemented with $0.25{\times}$ NLN microelements, followed by incubation at $25^{\circ}C$ for 30 days.

• Korean Journal of Plant Tissue Culture
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• v.24 no.6
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• pp.319-322
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• 1997

The optimal conditions for callus formation and plant regeneration were determined by the manipulation of culture method in unpollinated ovary culture of rice. The effect of cold pretreatment on callus formation and plant regeneration varied with duration of pretreatment. The maximum frequency (38.7%) of plant regeneration was obtained from the unpollinated ovary pretreated for 10 days at $12^{\circ}C$. The ability of callus formation and plant regeneration was higher on the medium with picloram (1 mg/L) than that of 2, 4-D (1 mg/L). However, the high concentration of picloram increased markedly the frequency of albino plant from unpollinated ovary-derived callus. Floral parts inoculated as a unit play important roles in callus formation and plant regeneration. Best result was obtained when ovary with partial cut glume, pedicel and secondary branch as a unit was cultured.

• The Korean Journal of Physiology
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• v.20 no.1
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• pp.9-15
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• 1986

The effect of dopamine on the propagation and the frequency electrical activities (slow wave) of the stomach was studied in isolated stomach muscle strips of 145 cats, The gastric slow wave monopolarly recorded by four capillary electrodes (Ag-AgCl) in Krebs-Ringer solution $(ph\;7.4,\;temperature\;36{\pm}0.5^{\circ}C)$ bubbled with 5% $CO_2$ in $O_2$. Dopamine caused concentration-dependent changes of direction of slow wave propagation with decline in development of irregular propagation by domperidone pretreatment. Dopamine also increased the variation of slow wave frequency concentration-dependently. The variation of slow wave frequency induced by dopamine was significantly inhibited by pretreatment with domperidone and phentolamine but not with propranolol, hexamethonium and tetrodotoxin. It is therefore suggested that dopamine plays a role in the genesis of gastric electrical abnormality acting on dopamine receptors and partly on ${\alpha}-adrenergic$ receptors in cats.

• Resources Recycling
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• v.26 no.5
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• pp.67-76
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• 2017

In order to efficiently recycle waste industrial nickel-cadmium batteries, anodic and cathodic materials were crushed by a cut mill and classified by sieves. We used wet magnetic separation method for eliminating iron components from the crushed powders. In addition, the acid leaching test for the obtained anode and cathode powders was carried out under various conditions by means of the wet process. At the optimum leaching conditions with 2.0 M $H_2SO_4$ at $90^{\circ}C$, 15 wt $H_2O_2$ and L/S=20 for 3 hours, the leaching efficiency of nickel and cadmium was 99%, respectively.

• Membrane and Water Treatment
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• v.2 no.3
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• pp.175-185
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• 2011

Ultrafiltration is an emerging technology for drinking water treatment because it produces better water quality as compared with conventional treatment systems. More recently, the combination of UF technology with other processes in order to improve its performance has been observed. These associations aim to maximize the contaminants removal and reduce membrane fouling. The operational performance of contaminants removal and water production of two UF pilot plants was compared. The first plant (Guarapiranga) was fed with raw water and the second plant (ABV) with pre-treated water by the coagulation, flocculation and sedimentation processes at Alto da Boa Vista WTP (Sao Paulo, Brazil). Both units operated continuously for approximately 2,500 hours, from September/2009 to January/2010. The results showed that the ABV UF pilot plant was able to operate at higher specific fluxes (6.2 $L.d^{-1}.m^{-2}.kPa^{-1}$ @ $25^{\circ}C$) than Guarapiranga (3.1 $L.d^{-1}.m^{-2}.kPa^{-1}$ @ $25^{\circ}C$). However, the number of chemical cleanings conducted in both pilot units during the considered operation period was the same (4 chemical cleanings for each plant), which shows that the pre-treatment reduced the membrane fouling. The water quality at ABV for all the variables analyzed was better, but the feed water quality was also better due to pretreatment. The rejection values for the different contaminants were higher at Guarapiranga mainly because of a pollution load reduction after pre-treatment at ABV. Even with the better performance of the ABV UF pilot plant, it is necessary to take into consideration the complexity of the complete treatment system, and also the costs involved in the construction and operation of a full-scale treatment unit.