• Journal of Bio-Environment Control
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• v.15 no.1
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• pp.84-90
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• 2006

This study was conducted to anticipate nitrate reduction state in tree through measurement of nitrate reductase activity (NRA) and investigate the effect of nitrogen concentrations (100, 200, 400, and 600 $mg\;L^{-1}$) on growth, the nitrogen content of various tissue, and NRA of pear (Pyrus pyrifolia cv. Niitaka) seedlings in sand culture. Nutrient solutions used in this experiment were adjusted to pH 6.5 and fixed the ratio of ammonium and nitrate to 1:3 and trickle-irrigated 3 times a day. Tree height and dry weight of various organs in seedlings were higher in low nitrogen concentration (100 and 200 $mg\;L^{-1}$) than in high nitrogen concentration (400 and 600 $mg\;L^{-1}$). The shoot growth in 600 $mg\;L^{-1}$ was extremely poor by nitrogen over supply. Increasing the nitrogen concentration, the concentration of nitrate-N in leaves and roots were insignificantly changed but that of stems increased. The accumulation of total and reduced nitrogen in all organs with increasing concentrations of nitrogen supply were increased at 30 days after treatment but those of all organs at 60 and 90 days after treatment were highest in 600 $mg\;L^{-1}$, whereas there were no significant changes among other nitrogen concentration. The in vivo (${+NO_3}^-$) NRA of all organs did not relate to nitrogen concentration but the in vivo (${-NO_3}^-$) NRA of leaves except roots increased with increasing the nitrogen concentration. Therefore, the proper nitrogen concentration to promote growth and nitrate reduction of pear tree was 200 $mg\;L^{-1}$.

• Preventive Nutrition and Food Science
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• v.13 no.3
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• pp.146-156
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• 2008

The enhancement of the human body fat reduction of conjugated linoleic acid (CLA) with the supplementation of $\gamma$-oryzanol (OZ) was investigated on overweight Korean women (n=51, BMI> 23). Subjects were divided into 4 groups of control, CLA, glyceride form of CLA (GCLA), and CLA plus OZ (CLA-OZ). The soft-gel capsule (500 mg) was used to deliver control (500 mg olive oil), CLA (500 mg CLA), GCLA (500 mg GCLA) and CLA-OZ (500 mg CLA plus 50 mg OZ). Three capsules were taken twice a day for 12 weeks. The CLA-OZ supplementation reduced 1.35% body fat that was 0.34% enhancement against CLA supplementation. As considered subject variations, CLA-OZ reduced body fat ranged from 7.9% to -2.7%, equivalent to 5.6 kg loss to 0.7 kg gain in body fat mass, against CLA. The CLA-OZ reduced body weight and body mass index (BMI), relative to control, but the reductions by CLA-OZ were not different from those by CLA and GCLA. All biochemical markers analyzed for safty were not significantly different within or between groups and were within the normal range. The CLA-OZ supplementation significantly reduced blood pressure, as compared to the supplementation of CLA, GCLA and control. These results suggest that OZ could be a useful ingredient to mix with CLA for the reduction of human body fat.

• Clean Technology
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• v.29 no.1
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• pp.39-45
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• 2023

To investigate the effects of Mg addition at different aging times and temperatures, Cu/MgO/Al₂O₃ catalysts were synthesized for the low-temperature water gas shift (LT-WGS) reaction. The co-precipitation method was employed to prepare the catalysts with a fixed Cu amount of 30 mol% and varied amounts of Mg/Al. Synthesized catalysts were characterized using XRD, BET, and H₂-TPR analysis. Among the prepared catalysts, the highest CO conversion was achieved by the Cu/MgO/Al₂O₃ catalyst (30/40/30 mol%) with a 60 ℃ aging temperature and a 24 h aging time under a CO₂-rich feed gas. Due to it having the lowest reduction temperature and a good dispersion of CuO, the catalyst exhibited around 65% CO conversion with a gas hourly space velocity (GHSV) of 14,089 h-1 at 300 ℃. However, it has been noted that aging temperatures greater or less than 60 ℃ and aging times longer than 24 h had an adverse impact, resulting in a lower surface area and a higher reduction temperature bulk-CuO phase, leading to lower catalytic activity. The main findings of this study confirmed that one of the main factors determining catalytic activity is the ease of reducibility in the absence of bulk-like CuO species. Finally, the long-term test revealed that the catalytic activity and stability remained constant under a high concentration of CO₂ in the feed gas for 19 h with an average CO conversion of 61.83%.

• Korean Journal of Environmental Agriculture
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• v.28 no.2
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• pp.165-170
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• 2009

The increase in P availability to rice under flooded soil conditions involves the reductive dissolution of iron phosphate and iron (hydr)oxide phosphate. However, since $NO_3^-$ is a more favourable electron acceptor in anaerobic soils than Fe, high$NO_3^-$ loads function as a redox buffer limiting the reduction of Fe. The effect of adding $NO_3^-$ on Fe reduction and P release in paddy soil was investigated. Pot experiment was conducted where $NO_3^-$ was added to flooded soil and changes of redox potential and $Fe_2^+$, $NO_3^-$ and $PO_4^{3-}$ concentrations in soil solution at 10 cm depth were monitored as a function of time. Redox potential decreased with time to -96 mV, but it was temporarily poised at about 330${\sim}$360 mV when $NO_3^-$ was present. Nitrate addition to soil led to reduced release of $Fe_2^+$ and prevented the solubilization of P. Phosphate in pore water began to rise soon after incubation and reached final concentrations about 0.82 mg P/L in the soil without $NO_3^-$ addition. But, in the soil with $NO_3^-$ addition, $PO_4^{3-}$ in pore water was maintained in the range of 0.2${\sim}$0.3 mg P/L. The duration of inhibition in $Fe_2^+$ release was closely related to the presence of $NO_3^-$, and the timing of $PO_4^{3-}$ release was inversely related to the $NO_3^-$ concentration in soil solution. The results suggest that preferential use of $NO_3^-$ as an electron acceptor in anaerobic soil condition can strongly limit Fe reduction and P solubilization.

• Journal of the Korean Ceramic Society
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• v.41 no.11
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• pp.842-850
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• 2004

We have investigated on the preparation of BaTiO$_3$ powder at the system of BaO$_2$-TiO$_2$-Reduction ag.-PSCA by SHS. C and Mg were used as reduction agent, and NaCl was used as PSCA (Particle Size Control Agent). The effects of the various reduction agent and its concentration, particle size control agent, reaction mixture mass on the product in the preparation of BaTiO$_3$ powder at the optimum system by SHS were investigated. The optimum conditions for reaction system and composition were BaO$_2$+TiO$_2$+0.11 Mg +0.2C+0.75NaCl in the As atmosphere. NaCl as PSCA showed the effect of controlling the particle size of product as well as the combustion temperature. The particle size of BaTiO$_3$ synthesized at the optimum condition was about 0.5 ${\mu}{\textrm}{m}$. And as the mixture mass for the reaction was increased, the more stable combustion wave appeared. We have conducted the sintering experiment at the temperature of 130$0^{\circ}C$, the time of 2 h and the atmosphere of air to measure the dielectric properties of BaTiO$_3$ synthesised in this work, and the sample sintered in this condition showed 2,290 of dielectric constant at 10$0^{\circ}C$ and 13,890 at curie point (129$^{\circ}C$).

• Journal of Nutrition and Health
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• v.53 no.6
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• pp.648-662
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• 2020

Purpose: Sodium intake is persistently decreasing because of the government's sodium reduction policy. This study aimed to identify foods and dishes that contributed to the reduction of sodium intake and evaluate the effects of the sodium reduction policy. Methods: The subjects were 57,809 participants in the Korea National Health and Nutrition Survey from 2010 to 2017. To identify food and dish sources of sodium intake, the food and dish groups were classified into 23 and 21 groups, respectively. Foods and dishes that contributed to sodium intake were categorized according to the production and cooking venues: production by manufacturers, home cooking, cooking at catering service, and restaurant cooking. Results: Sodium intake was 4,876 mg in 2010 to 3,477 mg in 2017, showing a 29.7% decrease in intake in 2010. Sodium intake was decreased mainly in foods produced by manufacturers and home-cooked foods. The main contributory factors to sodium from the food and dish groups differed according to the food manufacturer and cooking venue. The kimchi produced by manufacturers, cooked soup/tang/jjigae/hotpot at home and catering services, and cooked noodles/dumplings in restaurants were the main contributors to the sodium intake. Conclusion: The type of foods and dishes that contribute to sodium intake tended to expand over the years from specific foods and dishes to various groups of foods and dishes. These results provide evidence for the development and production of low-salt foods and dietary education related to low-salt intake.

• Journal of Korean Society of Environmental Engineers
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• v.36 no.5
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• pp.352-358
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• 2014

The feasibility of perchlorate reducing-bacteria isolated from the sludge of an anaerobic digester was determined using ammonium perchlorate in aqueous medium. Growth kinetics of the two perchlorate reducing bacteria including Rhodococcus sp. YSPW01 and YSPW02 were investigated using acetate as the electron donor in batch experiment. The growth of YSPW01 and YSPW02 reached a steady-state at 26 and 9 h, respectively. The initial perchlorate concentration was completely reduced within 8 and 7 h by YSPW01 and YSPW02, respectively. The reduction rates were 2.1 and $15mg\;L^{-1}h^{-1}$ for YSPW01, and 3.2 and $15.5mg\;L^{-1}h^{-1}$ for YSPW02, at 1:1 and 5:1 ratios of acetate:perchlorate (w:w), respectively. In this study, the bacteria Rhodococcus sp. YSPW01 and YSPW02 demonstrated a potential for the perchlorate reduction, which could be further investigated for development of an efficient strategy to treat the perchlorate contaminated waters.

• Journal of Korean Society of Environmental Engineers
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• v.27 no.10
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• pp.1052-1057
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• 2005

Recently, the ozone treatment of wasting activated sludge has become one of the effective and feasible process for the sludge reduction. The objective of this study is to investigate the availability of ozonized wasting sludge on external carbon sources 13r phosphorus release. Experiment results showed that the ozone treatment of activated sludge could produce a large amount of VFA such as acetic acid and isobutyric acid. For example, 50.24 mg/L acetic acid was produced with the ozone dose of 0.05 g $O_3/g$ SS, and 123.56 mg/L acetic acid with 0.5 g $O_3/g$ SS. The higher ozone dose was applied, the more VFA was produced from sludge reduction into a limited point. Finally, using ozonated sludge as only carbon source, the batch experiment, to measure phosphorus release rate in anaerobic condition were performed. The specific phosphorus release rates were investigated as 0.94, 1.37, 1.48, 1.68 mg P/g VSS/hr with ozone dose of 0.05, 0.1, 0.2, 0.5 g $O_3/g$ SS, respectively. Considering the degree of mineralization, VFA production, phosphorus release rate, and economical aspect, the optimal ozone dose for sludge reduction and using carbon sources ranged from 0.05 to 0.1 g $O_3/g$ SS.

• Toxicological Research
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• v.13 no.3
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• pp.193-196
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• 1997

Matricaria Chammomillal L., Foemiculum Vulgare mill, and Plantago Psylium L. have been screened for their hepato protective activities against liver damge induced by $CCl_4$ intoxication in mice. Hydroalcoholic extractions (2:8) of herbal drugs were concentrated in vacuo and concentrated crude extracts of Matrica Chammomilla L. and Foeniculum Vulgare mill were orally administered at doses of 100 mg/kg, 200 mg/kg, 400 mg/kg, and 800 mg/kg. Plantago Psyllium was given at doses of 50 mg/kg, 100 mg/kg, 200 mg/kg, and 400 mg/kg. Liver protective activities of these herbs were determined after administration of $CCl_4$ Liver size, serum enzyme activities, sleeping time, and histopatology of the liver were examined one hour after administration of $CCl_4$. ALT and AST activities, liver weight and sleeping time decreased in groups that received 400 mg/kg of Matricaria Chammomilla L. or Foeniculum Vulgare. Histological investigation showed significant increase in hepatic cell regeneration and reduction in liver injury. The group that received 100 mg/kg Plantago Psylium showed liver protection but protection was not significant in other doses.

• Journal of the Korean Society of Food Science and Nutrition
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• v.29 no.3
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• pp.525-530
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• 2000

상품가치가 없는 비상품구로부터 추출한 OWE를 mouse의 피부암 및 위장암 저해 효과에 관한 실험을 한 결과 피부암의 경우 control구에서는 6주부터 종양이 발생하여 23주에는 mouse 당 2.9개의 종양이 발생하였으나 20mg OWE 처리구에서는 8주부터 종양이 발생하여 23주에는 mouse 당 1.3개의 종양이 발생하여 control에 비해 55.2%의 종양 억제효과가 있었다. 20mg quercetin 처리에서는 6주부터 종양이 발생하기 시작하여 23주에는 mouse 당 1.2개의 종양이 발생하였다. 처리별 암 발생율은 20mg OWE 처리에서 85.7%, 20mg quercetin 처리에서는 76.2%의 발생율을 보여 control의 95.2%에 비해 낮은 암발생율을 보였다. 위장암의 경우 control에서는 mouse 당 9.2개의 종양이 발생하였고, 50mg OWE 및 25mg OWE 처리에서는 각 6.1, 6.3개의 종양이 발생하여 control에 비해 각각 33.7%, 31.5%의 종양억제효과가 있었다. 그리고 25mg quercetin 처리에서는 mouse 당 5.3개의 종양이 발생하였다. 처리별 암발생율은 50mg OWE 및 25 mg OWE 처리에서 각 88.2%, 94.1%, 25mg quercetin 처리에서 83.3%의 발생율을 보여 control 100%에 비해 낮은 암발생율을 보였다.