• Korean Journal of Weed Science
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• v.2 no.1
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• pp.31-40
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• 1982

For the effective control of weeds in mechanically transplanted paddy field weeding effects of naproanide ${\alpha}$-(${\beta}$-naphthoxy) propion anilide], pyrazolate [4-2, 4-dichlorobenzoyl)-1, 3-dimethyl pyrazol-5-yl-p-tolune sulphanate], chlormethoxynil (2, 4-dichloro-phenyl-4-nitro-3-methoxy phenyl ether), SL-49 [1-3dimethyl-4(2, 4dichlorobenzoyl)-5-phenacyloxy pyrazole], ACN (3-chloro-2-amino-l, 4-naphthoquinone) either alone or in combination with butachlor (2-chlor-2, 6-diethyl-N-buthoxymethyl acetanilide) were compared. Pyrazolate and SL-49 were most effective for the control of Sagittaria pygmaea MIQ. and Potomogeton distinctus A. BENN. including most annual weeds. Weeding effect of butachlor alone was very high for annuals, good for Cyperus serotinus ROTTB. and poor for S. pygmaea and P. distinctus. But the weeding effect of the combination of butachlor and pyrazolate was stronger than that of butachlor alone and therefore this mixture was effective for S. pygmaea, P. distinctus and C. serotinus including all the annual weeds. The combination of butachlor and SL-49 showed the same tendency as the combination of butachlor and pyrazolate. Naproanilide was not effective for the control of Echinochlor crusgalli P. BEAUV and less effective for Monochoria vaginalis PRESL, but excellent for S. pygmaea. By mixing butachlor with naproanilide weeding, spectrum for annuals and S. pygmaea was much increased by that for P. distinctus and C. serotinus was not satisfactory. ACN was not satisfactory for the control of all the tested weeds but the weeding effect was increased in general by mixing with butachlor. Chlormethoxynil was excellent for the control of annual weeds but it has no effect on C. serotinus, S. pygmaea and P. distinctus showing some initial controling effect but these weeds regrew afterwards. The weeding activity of ACN increased in combination with butachlor and the residual activity was stronger than that of ACN alone. A light crop injury was found at the initial period after treatments in all treated plots. The yield from all treated plots except those from plots treated with ACN, butachlor and naproanilide were not significantly different from the band weeded plot.

• Proceedings of the Korean Vacuum Society Conference
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• 2016.02a
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• pp.341-341
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• 2016

The discovery of light emission in nanostructured silicon has opened up new avenues of research in nano-silicon based devices. One such pathway is the application of silicon quantum dots in advanced photovoltaic and light emitting devices. Recently, there is increasing interest on the silicon quantum dots (c-Si QDs) films embedded in amorphous hydrogenated silicon-nitride dielectric matrix (a-SiNx: H), which are familiar as c-Si/a-SiNx:H QDs thin films. However, due to the limitation of the requirement of a very high deposition temperature along with post annealing and a low growth rate, extensive research are being undertaken to elevate these issues, for the point of view of applications, using plasma assisted deposition methods by using different plasma concepts. This work addresses about rapid growth and single step development of c-Si/a-SiNx:H QDs thin films deposited by RF (13.56 MHz) and ultra-high frequency (UHF ~ 320 MHz) low-pressure plasma processing of a mixture of silane (SiH4) and ammonia (NH3) gases diluted in hydrogen (H2) at a low growth temperature ($230^{\circ}C$). In the films the c-Si QDs of varying size, with an overall crystallinity of 60-80 %, are embedded in an a-SiNx: H matrix. The important result includes the formation of the tunable QD size of ~ 5-20 nm, having a thermodynamically favorable <220> crystallographic orientation, along with distinct signatures of the growth of ${\alpha}$-Si3N4 and ${\beta}$-Si3N4 components. Also, the roles of different plasma characteristics on the film properties are investigated using various plasma diagnostics and film analysis tools.

• Korean Journal of Agricultural Science
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• v.44 no.4
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• pp.513-518
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• 2017

Soybean, one of most widely used swine feed component in the world, contains non-starch polysaccharides (NSP). The digestive system of weaned pigs is not yet fully developed, and thus weaned pigs cannot easily digest diets based on corn and soybean meal. Dietary exogenous enzymes supplementation has been intensively investigated to assist digestion of anti-nutritional factors, such as NSP. This experiment was conducted to investigate the effects of dietary enzyme cocktail on growth performance, intestinal morphology, and nutrient digestibility of weaned pigs. A total 36 weaned pigs ($5.92{\pm}0.48kg\;BW$; 28 d old) were randomly allotted to 2 dietary treatments (3 pigs/pen, 6 replicates/treatment) in a randomized complete block design. The dietary treatments were a typical diet based on corn and soybean meal (CON) and CON with 0.05% enzyme cocktail (Cocktail; mixture of xylanase, ${\alpha}-amylase$, protease, ${\beta}-glucanase$, and pectinase). Pigs were fed their respective diets for 6 wk. Growth performance, morphology of ileum, apparent ileal digestibility (AID) and apparent total tract digestibility (ATTD) of dry matter, crude protein, and energy of weaned pigs were measured. No significant differences (p > 0.05) were observed for growth performance for the duration of the experimental period, and morphology of ileum, and nutrient digestibility between CON and Cocktail treatment groups. Therefore, the results from the current study indicated that enzyme cocktail supplementation in diets had no influence on growth performance, intestinal morphology, and nutrient digestibility of weaned pigs.

• Journal of Life Science
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• v.19 no.2
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• pp.179-184
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• 2009

Zinc is an essential trace element for human and plays an important biological role in antioxidant properties. We have been reported that zinc-enriched S. cerevisiae FF-10 contained 392 mg% in the YM basal and 3,193 mg% in the YM optimal medium. Antioxidative activity of FF-10 was tested in vitro models by DPPH (${\alpha},{\alpha}'$-diphenyl-${\beta}$-picrylhydrazyl) radical scavenging activity and lipid peroxidation using linoleic acid (LA) and rat liver homogenate. DPPH radical scavenging activity was higher in the cell-free extract of FF-10 cultured in the YM optimal medium (YMOM) than that in the YM basal medium (YMBM). The inhibition activity of lipid peroxidation using rat liver homogenate was shown in the following order: BHT > YMOM > YMBM and these values were dose dependently. The lipid peroxidation of the control mixture by ferric thiocyanate and TBA methods using LA was increased rapidly as typical peroxidation curve of LA from one day and the antioxidation activity of the cell free extracts by cultivating FF-10 in the YMOM were higher than that of the YMBM. Result of this study indicate that the cell-free extracts containing a high intercellular zinc of S. cerevisiae FF-10 cultured in YMOM showed strong antioxidation capacities in DPPH radical scavenging activity and lipid peroxidation using LA and rat liver homogenate.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.57 no.11
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• pp.2015-2022
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• 2008

The effect of content of $Al_2O_3+Y_2O_3$ sintering additives on the densification behavior, mechanical and electrical properties of the pressureless-sintered $SiC-ZrB_2$ electroconductive ceramic composites was investigated. The $SiC-ZrB_2$ electroconductive ceramic composites were pressurless-sintered for 2 hours at 1,700[$^{\circ}C$] temperatures with an addition of $Al_2O_3+Y_2O_3$(6 : 4 mixture of $Al_2O_3$ and $Y_2O_3$) as a sintering aid in the range of $8\;{\sim}\;20$[wt%]. Phase analysis of $SiC-ZrB_2$ composites by XRD revealed mostly of $\alpha$-SiC(6H), $ZrB_2$ and In Situ YAG($Al_5Y_3O_{12}$). The relative density, flexural strength, Young's modulus and vicker's hardness showed the highest value of 89.02[%], 81.58[MPa], 31.44[GPa] and 1.34[GPa] for $SiC-ZrB_2$ composites added with 16[wt%] $Al_2O_3+Y_2O_3$ additives at room temperature respectively. Abnormal grain growth takes place during phase transformation from $\beta$-SiC into $\alpha$-SiC was correlated with In Situ YAG phase by reaction between $Al_2O_3$ and $Y_2O_3$ additive during sintering. The electrical resistivity showed the lowest value of $3.l4{\times}10^{-2}{\Omega}{\cdot}cm$ for $SiC-ZrB_2$ composite added with 16[wt%] $Al_2O_3+Y_2O_3$ additives at 700[$^{\circ}C$]. The electrical resistivity of the $SiC-TiB_2$ and $SiC-ZrB_2$ composite was all negative temperature coefficient resistance (NTCR) in the temperature ranges from room temperature to 700[$^{\circ}C$]. Compositional design and optimization of processing parameters are key factors for controlling and improving the properties of SiC-based electroconductive ceramic composites.

• Journal of Electrical Engineering and Technology
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• v.6 no.4
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• pp.543-550
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• 2011

Conductive SiC-$ZrB_2$ composites were produced by subjecting a 40:60 (vol%) mixture of zirconium diboride (ZrB2) powder and ${\beta}$-silicon carbide (SiC) matrix to spark plasma sintering (SPS). Sintering was carried out for 5 min in an argon atmosphere at a uniaxial pressure and temperature of 50 MPa and $1500^{\circ}C$, respectively. The composite sintered at a heating speed of $25^{\circ}C$/min and an on/off pulse sequence of 12:2 was denoted as SZ12L. Composites SZ12H, SZ48H, and SZ10H were obtained by sintering at a heating speed of $100^{\circ}C$/min and at on/off pulse sequences of 12:2, 48:8, and 10:9, respectively. The physical, electrical, and mechanical properties of the SiC-$ZrB_2$ composites were examined and thermal image analysis of the composites was performed. The apparent porosities of SZ12L, SZ12H, SZ48H, and SZ10H were 13.35%, 0.60%, 12.28%, and 9.75%, respectively. At room temperature, SZ12L had the lowest flexural strength (286.90 MPa), whereas SZ12H had the highest flexural strength (1011.34 MPa). Between room temperature and $500^{\circ}C$, the SiC-$ZrB_2$ composites had a positive temperature coefficient of resistance (PTCR) and linear V-I characteristics. SZ12H had the lowest PTCR and highest electrical resistivity among all the composites. The optimum SPS conditions for the production of energy-friendly SiC-$ZrB_2$ composites are as follows: 1) an argon atmosphere, 2) a constant pressure of 50 MPa throughout the sintering process, 3) an on/off pulse sequence of 12:2 (pulse duration: 2.78 ms), and 4) a final sintering temperature of $1500^{\circ}C$ at a speed of $100^{\circ}C$/min and sintering for 5 min at $1500^{\circ}C$.

• Journal of Electrical Engineering and Technology
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• v.8 no.6
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• pp.1474-1480
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• 2013

Silicon carbide (SiC)-zirconium diboride ($ZrB_2$) composites were prepared by subjecting a 60:40 vol% mixture of ${\beta}$-SiC powder and $ZrB_2$ matrix to spark plasma sintering (SPS) in 15 $mm{\Phi}$ and 20 $mm{\Phi}$ molds. The 15 $mm{\Phi}$ and 20 $mm{\Phi}$ compacts were sintered for 60 sec at $1500^{\circ}C$ under a uniaxial pressure of 50 MPa and argon atmosphere. Similar composites were simulated using $Flux^{(R)}$ 3D computer simulation software. The current and power densities of the specimen sections of the simulated SiC-$ZrB_2$ composites were higher than those of the mold sections of the 15 $mm{\Phi}$ and 20 $mm{\Phi}$ mold simulated specimens. Toward the centers of the specimen sections, the current densities in the simulated SiC-$ZrB_2$ composites increased. The power density patterns of the specimen sections of the simulated SiC-$ZrB_2$ composites were nearly identical to their current density patterns. The current densities of the 15 $mm{\Phi}$ mold of the simulated SiC-$ZrB_2$ composites were higher than those of the 20 $mm{\Phi}$ mold in the center of the specimen section. The volume electrical resistivity of the simulated SiC-$ZrB_2$ composite was about 7.72 times lower than those of the graphite mold and the punch section. The power density, 1.4604 $GW/m^3$, of the 15 $mm{\Phi}$ mold of the simulated SiC-$ZrB_2$ composite was higher than that of the 20 $mm{\Phi}$ mold, 1.3832 $GW/m^3$. The $ZrB_2$ distributions in the 20 $mm{\Phi}$ mold in the sintered SiC-$ZrB_2$ composites were more uniform than those of the 15 $mm{\Phi}$ mold on the basis of energy-dispersive spectroscopy (EDS) mapping. The volume electrical resistivity of the 20 $mm{\Phi}$ mold of the sintered SiC-$ZrB_2$ composite, $6.17{\times}10^{-4}{\Omega}cm$, was lower than that of the 15 $mm{\Phi}$ mold, $9.37{\times}10^{-4}{\Omega}{\cdot}cm$, at room temperature.

• Journal of Pharmaceutical Investigation
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• v.27 no.4
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• pp.303-311
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• 1997

Proliposomal patch of clenbuterol, ${\beta}_2-agonist$ bronchodilator, was prepared and its feasibility as a novel transdermal drug delivery system was examined. Proliposomal granules containing clenbuterol was prepared by a standard method using sorbitol and lecithin with (Rx 2) or without cholesterol (Rx 1). The porous structure of sorbitol in the proliposomes was maintained allowing tree flowability of the granules. Following contact with water, the granules were converted probably to liposomes almost completely within several minutes. It indicates that proliposomes may be hydrated, when they are applied on the skin under occlusive condition in vivo, by the sweat to form liposomes. Clenbuterol release from Rx 1 and Rx 2 proliposomes to pH 7.4 isotonic phospate buffer (PBS) across cellulose membrane (mol. wt. cut-off of 12000-14000) was retarded significantly compared with that from the mixture of clenbuterol powder and blank proliposomes. Interestingly, proliposomes prepared with lecithin and cholesterol (i.e., Rx 2 proliposomes) showed much more retarded release of clenbuterol than proliposomes prepared only with lecithin (i.e.. Rx 1 proliposomes), indicating that clenbuterol release from proliposomes can be controlled by the addition of cholesterol to the proliposomes. Proliposomal patches were prepared using PVC film as an occlusive backing sheet, two sides adhesive tape (urethane, 1.45 mm thickness) as a reservoir for proliposome granules and Millipore MF-membrane (0.45 mm pore size) as a drug release-controlling membrane. Rx 1 or Rx 2 proliposomes containing 4.6 mg of clenbuterol were loaded into the reservoir of the patch. Clenbuterol release from the patches to pH 7.4 PBS was determined using USP paddle (50 rpm)-over-disc release method. Clenbuterol release from the proliposomal patches was much more retarded even than from a matrix type clenbuterol patch (Boehringer Ingelheim ltd). Being consistent with clenbuterol release from the proliposomal granules, the release from the patches was highly dependent on the presence of cholesterol in the proliposomes : Patches containing Rx 2 proliposomes showed several fold slower drug release than patches containing Rx 1 proliposomes. When the patch containing Rx 1 proliposomes was applied on to the back of a hair-removed rat, clenbuterol concentration in the rat blood was maintained during 6-72 hrs. Transdermal absorption of clenbuterol from the patch was accelerated when the patch was prehydrated with 50 ml of pH 7.4 PBS before topical application. Above results indicate that sustained transdermal delivery of clenbuterol is feasible using proliposomal patches if the cholesterol content and pore size of the release rate-controlling membrane of patches, for example, are appropriately controlled.

• Applied Biological Chemistry
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• v.48 no.4
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• pp.431-434
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• 2005

The quantitative analytical method for major antioxidants, ellagic acid and punicalagin, in pomegranate husk (Granati pericarpium) were established by HPLC. The optimal HPLC conditions were as follows: Column; Agilent Zorbax Eclipse XDB-C18 ($4.6{\times}150mm,\;5{\mu}m$), mobile phase; 1% formic acid in water (A) and 1% formic acid in MeCN (B) (gradient elution of 5% to 100% B for 50 min), flow rate; 0.8 ml/min., detection; UV 254 nm. The optimal pre-treatment conditions for HPLC analysis were as follows: 5 g of pomegranate husk in 100 ml of 95% EtOH, refluxed for 3 h. Under these analytical conditions, punicalagin and ellagic acid contents in Korean pomegranates husks which were cultivated in five different sites were determined. As results, the ellagic acid and punicalagin (as a mixture of ${\alpha-\;and\;{\beta}-anomer$) contents were the highest in Haepyung pomegranate husk $(15.27{\mu}g/mg)$ and Jangsung pomegranate husk $(16.21{\mu}g/mg)$, respectively.

• Asian-Australasian Journal of Animal Sciences
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• v.25 no.1
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• pp.66-74
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• 2012

The effects of exogenous fibrolytic enzymes (EFE; a mixture of two preparations from Trichoderma spp., with predominant xylanase and ${\beta}$-glucanase activities, respectively) on colonization and digestion of ground barley straw and alfalfa hay by Fibrobacter succinogenes S85 and Ruminococcus flavefaciens FD1 were studied in vitro. The two levels (28 and 280 ${\mu}g$/ml) of EFE tested and both bacteria were effective at digesting NDF of hay and straw. With both substrates, more NDF hydrolysis (p<0.01) was achieved with EFE alone at 280 than at 28 ${\mu}g$/ml. A synergistic effect (p<0.01) of F. succinogenes S85 and EFE on straw digestion was observed at 28 but not 280 ${\mu}g$/ml of EFE. Strain R. flavefaciens FD1 digested more (p<0.01) hay and straw with higher EFE than with lower or no EFE, but the effect was additive rather than synergistic. Included in the incubation medium, EFE showed potential to improve fibre digestion by cellulolytic ruminal bacteria. In a second batch culture experiment using mixed rumen microbes, DM disappearance (DMD), gas production and incorporation of $^{15}N$ into particle-associated microbial N ($^{15}N$-PAMN) were higher (p<0.001) with ammoniated (5% w/w; AS) than with native (S) ground barley straw. Application of EFE to the straws increased (p<0.001) DMD and gas production at 4 and 12 h, but not at 48 h of the incubation. EFE applied onto S increased (p<0.01) $^{15}N$-PAMN at 4 h only, but EFE on AS increased (p<0.001) $^{15}N$-PAMN at all time points. Prehydrolysis increased (p<0.01) DMD from both S and AS at 4 and 12 h, but reduced (p<0.01) $^{15}N$-PAMN in the early stage (4 h) of the incubation, as compared to non-prehydrolyzed samples. Application of EFE to barley straw increased rumen bacterial colonization of the substrate, but excessive hydrolytic action of EFE prior to incubation decreased it.