• Food Science and Biotechnology
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• v.16 no.1
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• pp.159-162
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• 2007

Optimization of the fermentation medium for phenylethyl alcohol (PEA) production by Pichia anomala SKM-T was performed. The carbon source (glucose), nitrogen source (L-phenylalanine), and initial pH value were independent variables of the optimized medium. The central composite rotatable design was used for the experimental design and the analysis of the results. The optimum medium composition for the maximal production (621.27 mg/L) of PEA was found to be an initial pH of 5.03, and concentrations of L-phenylalanine at 6.53 and glucose at 6.11 g/L (w/v). This experimental finding is in close agreement with the model prediction (702.79 mg/L; desirability 0.884) with an 11.6% difference.

• Journal of the Korean Ceramic Society
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• v.36 no.8
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• pp.799-804
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• 1999

Composites of SiC-Si3N4 consisted of uniformly distributed elongated $\beta$-Si3N4 grains and equiaxed $\beta$-SiC grains were fabricated with $\beta$-SiC,. $\alpha$-Si3N4 Al2O3 and Y2O3 powders. By hot-pressing and subsequent annelaing elongated $\beta$-Si3N4 grains were grown via$\alpha$longrightarrow$\beta$ phase transformation and equiaxed $\beta$-Si3N4 composites increased with increasing the Si3N4 content owing to the reduced defect size and enhanced crack deflection by elongated $\beta$-Si3N4 grains and the grain boundary strengthening by nitrogen incorporation. Typical flexural strength and fracture toughness of SiC-40 wt% Si3N4 composites were 783 MPa and 4.2 MPa.m1/2 respectively.

• Korean Journal of Microbiology
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• v.9 no.3
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• pp.95-102
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• 1971

The growth characteristics of Candida tropicalis KIST 351 on gas oil substrate under different culture conditions were investigated and the preliminary animal feeding experiments using this yeast as a partial substitute of fish meal was also conducted. The yeast assimilates effectively n-paraffins in gas oil ranging from $C_{16}$ to $C_{16}$ with its maximum cell growth at $33^{\circ}C$ and pH 5.5 with aeration of 3 vvn and agitation of 900 rpm. The optimal concentrations of nitrogen sources, $HK_2PO_4$ and $Na_2HPO$ were 4, 2 and 0.5g/1, respectively. Ferrous sulfate, manganese sulfate and zinc sulfate showed positive effect to cell growth with the optimal range of 5-10 ppm. In the feeding experiment with 3 and 5% incorporation of the gas oil grown yeast, neither adverse effects on growth of chicks nor toxic effect were observed. Protein content of the dried cell was 58.8% and its amino acid composition compared well with other single-cell protein products and FAO reference protein.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2003.07b
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• pp.1231-1234
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• 2003

A sample procedure has been described to room temperature synthesis, mesoporous aluminosilicate materials with strong surface acidity by using a cationic surfactnat cetyltrimethylammonium bromide(CTABr) as the template agent. All samples were charecterized by X-ray diffraction(XRD) and nitrogen adsorption. The crystallinity and surface area of MCM-41 type aluminosilicats decrease with decreasing of Si/Al ratio. The influence of the aluminum contents of MCM-41 on the coordination of Al and on the acidity is studied by $^{27}Al$ MAS NMR and temperature programmed desorption of ammonia(TPD). It was shown that the incorporation of Al atoms into the framework causes increasing of acid site surface. And then Al atoms in the framework were incorporated tetrahedrally in structure, which gave a rise to cationic sites in the framework.

• Korean Journal of Soil Science and Fertilizer
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• v.41 no.4
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• pp.247-253
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• 2008

Winter annual green manure crops may be an effective tool for environmental-friendly agriculture system. The effect of legume (hairy vetch), non-legume (rye) and N fertilization ($190kg\;N\;ha^{-1}$) was examined and compared on red-pepper yield, nitrogen uptake, carbohydrate composition, and soil N and C contents. We monitored soil N and C for 120 days after incorporation (DAI) of green manures or mineral fertilizer. The mineralization of nitrogen reached the maximum around 30 DAI. The amount of inorganic nitrogen supplied by mineralization of hairy vetch residue was greater with than chemical N or rye. Photosynthetic rate was similar by 70 DAT in all treatments however, it in rye-incorporated red-pepper presented a sharp decline at later growth period. Leaf total nitrogen was greater with hairy vetch and chemical N than rye throughout the experiment. The soluble sugar increased steadily in all treatments from 40 to 110 days after transplanting (DAT) whereas starch showed a tendency of great decrease. Hairy vetch greatly promoted red-pepper growth by the later period however, chemical N showed the highest fruit yields.

• Journal of the Korean Vacuum Society
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• v.19 no.1
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• pp.14-21
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• 2010

Ge is one of the attractive channel materials for the next generation high speed metal oxide semiconductor field effect transistors (MOSFETs) due to its higher carrier mobility than Si. But the absence of a chemically stable thermal oxide has been the main obstacle hindering the use of Ge channels in MOS devices. Especially, the fabrication of gate oxide on Ge with high quality interface is essential requirement. In this study, $HfO_xN_y$ thin films were prepared by plasma-enhanced atomic layer deposition on Ge substrate. The nitrogen was incorporated in situ during PE-ALD by using the mixture of nitrogen and oxygen plasma as a reactant. The effects of nitrogen to oxygen gas ratio were studied focusing on the improvements on the electrical and interface properties. When the nitrogen to oxygen gas flow ratio was 1, we obtained good quality with 10% EOT reduction. Additional analysis techniques including X-ray photoemission spectroscopy and high resolution transmission electron microscopy were used for chemical and microstructural analysis.

• Korean Journal of Environmental Agriculture
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• v.31 no.4
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• pp.308-312
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• 2012

BACKGROUND: The nutrient balance in Korea during 1985-2006 had continually increased and maintained the highest levels among OECD countries. The use of green manure crops such as barley and hairy vetch is common practice for reducing chemical fertilizer application and maintaining soil fertility. However, green manure crops can also be used as a livestock feeding material which may reduce nutrient balance in the national scale. We calculated nitrogen and phosphate balance under green manure-rice cultivating system where all green manure was removed and used for feeding livestock. METHODS AND RESULTS: The barley and hairy vetch grown in pure stands or in mixtures with different sowing rates were tested for rice cultivation without chemical fertilization. The conventional fertilization (NPK) for rice cultivation was selected to compare nutrient balance with green manure-rice cultivation. Nitrogen and phosphate balance were calculated according to the surface balance method of the PARCOM guidelines. Total aboveground biomass of mixture (barley and hairy vetch) was higher compared to that of pure barley or hairy vetch. Among the mixture with barley and hairy vetch, the highest aboveground biomass was observed in B75H25 (barley 75%+hairy vetch 25%). The nitrogen and phosphate balance in the B75H25 mixture was-104 kg N/ha and-50.3 kg P/ha, respectively. CONCLUSION(S): The barley and hairy vetch mixture proved to be a very effective strategy for biomass production of green manure. The amount of nitrogen and phosphate fertilizer to be applied is estimated to be 104 kg N/ha and 50.3 kg P/ha in order to maintain soil fertility if all green manure and rice straw were removed from rice field for livestock feeding.

• Asian-Australasian Journal of Animal Sciences
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• v.14 no.9
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• pp.1228-1232
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• 2001

Forty five Soviet Chinchilla rabbits weaned at 35 d of age were fed 5 experimental diets prepared by using oat plant meal ($T_2,\;T_4$) and tall fescue hay ($T_3,\;T_5$) at 25% and 50% level along with control ($T_1$). The gain in body weight at 84 d of age decreased with test material substitution, however, the differences were non significant when compared with oat plant meal and were significant (p<0.05) with tall fescue hay at both the levels. Feed conversion ratio also deteriorated with test material and its increasing proportion and the differences were significant (p<0.05). The performance-index calculated were 42.1, 36.7, 29.4, 33.3 and 18.8 in $T_1,\;T_2,\;T_3,\;T_4$ and $T_5$, respectively. Digestibility of all the organic nutrients decreased significantly (p<0.05) with test material incorporation, as a result nutritive value of the test diets decreased linearly. Nitrogen balance as per cent of intake was higher in oat plant meal substituted diet compared to tall fescue substituted diet. Cost per kg live weight gain was lowest with 50% oat plant meal followed by 25% oat plant meal incorporation. It was highest with tall fescue hay substitution. Nutritive value of oat plant meal as calculated was DCP 5.1%, TDN 35.8% and that of tall fescue hay was DCP 6.5%, TDN 30.8%. Thus, oat plant meal can be substituted safely up to 25% in the feeding regime of weaner rabbits whereas, for tall fescue hay the safe limit is below 25% level and needs to be ascertained.

• Korean Journal of Soil Science and Fertilizer
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• v.46 no.4
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• pp.270-275
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• 2013

Hairy vetch can fix nitrogen from the atmosphere as a leguminous cover crop. This research was carried out to determine optimum seeding method of hairy vetch and application effect in paddy. Field experiment was conducted at Sinheung series (fine loamy, mixed, nonacid, mesic family of Fluvaquentic Endoaquepts) from Sep. 2011 to Oct. 2012 at the National Institute of Crop Science (NICS), RDA, Suwon, Gyeonggi province, Korea. Hairy vetch used in the study was 'Cheongpyungbora', developed by National Institute of Crop Science. Seeding methods of hairy vetch consisted of Broadcasting Before Rice Harvesting (BBRH), Partial Tillage Seeding (PTS), Minimum Tillage Seeding (MTS), No Tillage Seeding (NTS), and Drill Seeding (DS). Both MTS and NTS showed the highest biomass among the seeding methods. The rice yield of MTS and NTS significantly increased compared to conventional fertilization (CF). Also soil properties including organic matter and bulk density were improved by incorporation of hairy vetch. Therefore, we suggested that MTS and NTS could be used to produce hairy vetch and rice in paddy.

• Journal of the Korean Ceramic Society
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• v.54 no.2
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• pp.108-113
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• 2017

The use of aluminum-based coagulants in water pretreatment is being carefully considered because aluminum exposure is a risk factor for the onset of Alzheimer's disease. Lightly burned-dolomite kiln dust (LB-DKD) was evaluated as an alternative coagulant because it contains high levels of the healthful minerals calcium and magnesium. An organic pore forming agent (OPFA) was incorporated to prepare porous granules after OPFA removal through a thermal decomposition process. A spray drying method was used to produce uniform and reproducible spherical granules with low density, since fine dolomite particles have irregular agglomeration behavior in the hydration reaction. The use of fine dolomite powder and different porosity granules led to a visible color change in raw algae (RA) containing water, from dark green to transparent colorlessness. Also, dolomite powders and granules exhibited a mean removal efficiency of 48.3% in total nitrogen (T-N), a gradual increase in the removal efficiency of total phosphorus (T-P) as granule porosity increased. We demonstrate that porous dolomite granules can improve the settling time and water quality in summer seasons for the emergent treatment of excessive algal blooms in eutrophic water.