• Journal of the Korean Electrochemical Society
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• v.5 no.3
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• pp.106-110
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• 2002

Gel-type polyacrylonitrile(PAN) polymer electrolytes have been prepared using ethylene carbonate(EC), propylene carbonate(PC) and dimethyl carbonate(DMC) plasticizer, $LiPF_6$ salt and $TiO_2$ ceramic filler. Electrochemical properties, such as electrochemical stability, ionic conductivity and compatibility with lithium metal and mechanical properly of polymer electrolytes were investigated. Charge/discharge performance of lithium secondary battery using these polymer electrolytes were investigated. The maximum load that the polymer electrolyte resists increased about two times as a result of adding $TiO_2$ in the polymer electrolyte containing EC and PC. Polymer electrolyte containing EC, PC and $TiO_2$ also showed ionic conductivity of $2\times10^{-3} S/cm$ at room temperature and electrochemical stability window up to 와 4.5V. Polymer electrolyte containing EC, PC, and $TiO_2$ showed the most stable interfacial resistance of $130\Omega$ during 20 days in the impedance spectra of the cells which were constructed by lithium metals as electrodes. Lithium metal secondary battery which employed $LiCoO_2$ cathode, lithium metal anode and $TiO_2$-dispersed polymer electrolyte showed $90\%$ of charge/discharge efficiency at the 1C rate of discharge.

• Applied Chemistry for Engineering
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• v.9 no.5
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• pp.734-741
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• 1998

Electrode characteristics were studied in the interface between sample solutions and $K^+$ ion selective PVC membrane electrodes containing neutral carriers, dibenzo-18-crown-6(D18Cr6) and valinomycin(Val). The effect of doping of base electrolytes, the chemical structure and the content of carrier, variation of plasticizer, membrane thickness, and concentration variation of sample solution on the response characteristics of electrode such as the measured Nernstian slope, the detection limit, the linear response range, and potentiometric selectivity coefficients, were studied. In order to synthesize the membrane D18Cr6 and Val as neutral carriers were used, and complex between the carrier and $K^+$ ions were used as active materials. PVC membrane electrodes were made of plasticizers (DBP, DOS, and DBS), the base electrolyte[potassium tetraphenylborate(KTPB)], and solvent(THF). The chemical structure of carrier D18Cr6 was best for electrode and ideal electrode characteristics were appeared especially in case of doping of TPB. The optimum carrier content was about 3.23 wt % in case of D18Cr6 and Val. DBP was best as a plasticizer. As membrane thickness decreased the electrode characteristics was improved. But its characteristics were lowered below the optimum membrane thickness because of the elution of carrier, deterioration of membrane strength, etc. In the case of D18Cr6, the selectivity coefficients by the mixed solution method for the $K^+$ ion were in the order of $NH_4{^+}>Ca^{2+}>Mg^{2+}>Na^+$.

• Polymer(Korea)
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• v.32 no.2
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• pp.169-177
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• 2008

The thermal and optical properties of cellulose tri(cholesteryloxy) carbonate(CCE0) and cellulose tri(cholesteryloxycarbonyl)alkanoates (CCEn, n=$2{\sim}8$, 10, the number of methylene units in the spacer) were investigated. CCE0 formed an enantiotropic cholesteric phase, whereas all the CCEn exhibited monotropic cholesteric phases. CCEn with n=$3{\sim}8$ formed cholesteric phases with left-handed helical structures whose optical pitches (${\lambda}_m's$) decrease with increasing temperature. On the other hand, CCE0 and CCEn with n=2 or 10 did not display reflection colors over the full cholesteric range, suggesting that the helical twisting power of the cholesteryl group highly depends on the length of the spacer connecting the cholesteryl group to the main chain. The thermal stability and degree of order in the mesophase and the temperature dependence of the ${\lambda}_m$ observed for CCEn highly depended on n. The results were discussed in terms of the differences in the internal plasticization, the arrangement of the side groups, and the conformation of the molecules.

• Journal of Mushroom
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• v.10 no.4
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• pp.236-243
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• 2012

Spent mushroom substrates is composted organic material remaining after a crop of mushroom is harvested. The raw materials of mushroom substrates are same feed ingredient as corncobs, rice brown, wheat brown, cotton seeds and beet pulp. During the mushroom cultivation process, the mushroom substrates was used 15-25% by mushroom and 75-85% of mushroom substrates was remained in the SMS. Among of the spent mushroom substrates, spent mushroom substrates of pleurotus eryngii, Pleurotus ostreatus and Flammuliua velutipes is can be use the energy feedstock of animal feed. The cellulose content of spent mushroom(pleurotus eryngii) substrates containing the sawdust was high and total digestible nutrients (TDN) values was low. The spent mushroom(pleurotus eryngii) substrates fermented with cellulase and xylanase producing bacteria is may be used as an ingredient of feed in TMR for Hanwoo steer.

• Korean journal of applied entomology
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• v.54 no.4
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• pp.359-367
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• 2015

Physiological plasticity of insects can be closely related with their epigenetic change. This hypothesis was tested using a polyphagous lepidopteran insect, Spodoptera exigua, by assessing the effects of different diets on development and DNA methylation. Three different diets (Welsh onion (WO), Chinese cabbage (CC), artificial diet (AD)) were assessed by feeding a cohort of larvae from neonate to last instar. There were significant differences in larval developmental rate, pupal weight and adult emergence according to diet treatments. AD-fed larvae exhibited the fastest developmental rate along with the highest pupal weight and adult emergence. Among natural hosts, WO was more favorable for development of S. exigua than CC. Total hemolymph proteins and sugars in the last instar larvae were varied among different diets. Gene expression of an insulin-like peptide (SeILP1) presumably associated with development was also varied among diets. Cytosine methylation of genomic DNA was assessed using a monoclonal antibody. Genomic DNA of S. exigua larvae was methylated. DNA methylation was apparently varied among different diet-fed larvae. The facts that a cohort of S. exigua was differentiated in developmental rate and cytosine methylation by different diets suggest that epigenetic factor(s) may play a crucial role in the physiological plasticity.

• Journal of The Korean Society of Grassland and Forage Science
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• v.19 no.1
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• pp.11-16
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• 1999

This study was conducted to compare the dry matter intake, the digestibility, and utilization of nitrogen and energy of Korean native goats, when fed on orchardgrass(OG) mixed with alfalfa(AA) at a different levels. Experimental diets include three treatments : OG 100%, OG 80%+AA 20%, and OG 60%+AA 40%. With increasing levels of AA supplementation, the content of CP was higher for AA supplemented diets than for OG 100% diets, while the content of NDF, ADF, hemicellulose and lignin content were slightly lower for AA supplemented diets than for OG 100% diets. Also, the DM intake and the digestibility of DM, cellular constituents, NDF and ADF were higher for AA supplemented diets than for OG 100% diets, especially those were the highest in OG 60%+AA 40% diets(P<0.05). The apparently digested N, retained N and biological value of AA supplemented diets were increased with increasing levels of AA supplementation, compared with those of OG 100% diets(P<0.05). The utilization of DE and ME were slightly high in OG 60%+AA 40% diets, but there was no significant difference among all diets. According to the results, DM intake, digestibility and nitrogen utilization were improved in goat fed diets with supplementation AA(AA 20%, 40%), compared with those of OG 100% diets. But energy utilization did not show the difference among diets. Hence, It needs to provides to the adequate energy sources to goats.

• Journal of The Korean Society of Grassland and Forage Science
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• v.19 no.3
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• pp.189-196
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• 1999

This study was conducted to evaluate the dry matter yield, quality and utilization of nutrients of wild Korean lespedeza as a forage legume sources. Dry matter(DM) yield of stages, chemical composition and DM digestibility were observed, also DM intake, digestibility and utilization of nitrogen and energy by Korean native goats were determined. Experimental diets include three treatrnents ; mixture grass hay(GS), GS 80% + lespedeza(LA) 20% and GS 60% + LA 40%, respectively. The DM yield of Korean lespedeza(LA) with advancing the growing stage tended to significantly increase(P<0.05). The average DM yield was observed 7,336kg/ha. CP content of LA tended to decrease, but fiber content tended to increase at growing stage advanced(P<0.05). The tannin content of LA was highest in bud stage (54.5mg/g), but tended to decrease at growing stage advanced, lowest in seed ripe stage(26.8mg/g) (P<0.05). With increasing the level of LA supplementation, DM intake by Korean native goats slightly increased, but no differences were observed in all diets. The digestibility of DM, cellular constituents and NDF were slightly lower for GS 100% diets than LA 20% and 40% supplemented diets(P<0.05). Apparently digested N% was not detected significant differences in all diets, but retained N and biological value were higher for LA supplemented diets than for GS 100% diets (P<0.05). Utilization of DE and ME was not detected significant differences in all diets. Above the results, it could be suggested that LA have a potential to provide as forage legume sources considering the DM yield, DM digestibility and nitrogen utilization.

• Journal of The Korean Society of Grassland and Forage Science
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• v.31 no.4
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• pp.345-352
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• 2011

Soil fertility different depend on application rate of manure and compost for many years. While each crop has different adaptability depend on soil fertility, crop and species or varieties should be chosen depending on the adaptability and productivity. These experiments were carried out to compare the five winter cereal crops for whole crop silage on growth, yield and feed value as affected by soil organic content. The rate of increase on no. of spikes at high fertile soil compared with medium fertile soil was sequently high Samhan (Oat's variety) > Cheongwoo (Wheat) > Gogu (Rye) > Youngyang (Barley) > Shinyoung (Triticale). The rate of decrease at low fertile soil compared with medium fertile soil was sequently high Youngyang > Gogu > Cheongwoo > Shinyoung > Samhan. The triticale was lower variation of no. of spikes as affected by soil organic content than that of other winter cereals. The variations of dry matter yield as affected by soil fertility was higher oat and barley and lower triticale. Forage yield of triticale was higher about 69 percent than that of barley at low fertile soil. Forage yield was the highest in triticale and the lowest in rye in all soil fertility. In high fertile soil, rate of increasing digestible dry matter (DDM) yield compared with medium fertile was high in Samhan and Youngyang. Rate of reduced DDM yield in low fertile soil compared with medium fertile was low in Shinyoung and Cheongwoo.

• Journal of The Korean Society of Grassland and Forage Science
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• v.29 no.3
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• pp.187-196
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• 2009

The objectives of this study were to evaluate the different cutting dates on the changes of feed quality among five cereals (barley, wheat, rye, triticale and oat) for whole crop silage. Field trials were conducted at paddy field in Yesan, Chungnam Province and the aerial parts were clipped 10 days from 15 March to 15 June. Changes of acid detergent fiber (ADF) content in relation to different cutting dates was described by a quadratic curve for 5 winter cereals crops. ADF content reached a maximum at 5 days after heading in barley cultivar 'Youngyang', 7 days in wheat 'Keumkang', 18 days in rye 'Gogu', 1 days in triticale 'Shinyoung' and 10 days in oat 'Samhan'. Neutral detergent fiber (NDF) content were linearly increased as growing after overwintering and stagnated or slightly decreased after heading. The crude protein were linearly decreased throughout the growth period of 5 whole crop cereals. Digestible dry matter (DDM) content were decreased from early stages to heading and subsequently increased as grain filling. Relative feed value (RFV) for 5 crops were decreased as growing and subsequently increased as grain filling after heading. Barley cultivar for only forage use 'Youngyang' were lower at ADF and NDF content and higher at DDM and RFV after heading than those of other cereals for forage use. So, barley for whole crop silage was a good crop with high feed quality and high proportion of spikes compared with other winter cereal crops. Wheat cultivar for grain 'Keumkang' were higher at crude protein than those of other four cereals from overwintering to maturing and were higher at DDM and RFV after heading than those of rye, triticale and oat. Rye cultivar with cold tolerant and high fresh yielding 'Gogu' were highest at ADF and NDF content and lowest at DDM content and RFV. So, rye was a crop with low quality for forage use compared to other winter cereal crops. Triticale cultivar with flourishing and high yielding 'Shinyoung' was intermediated between barley and rye, and were linearly increased at DDM yield by different cutting dates. Oat cultivar with cold tolerant and high tillering 'Samhan' were lower at ADF and NDF content and higher at crude protein before heading, but after heading, there are not especially advantages compared to barley, wheat or triticale.

• Journal of The Korean Society of Grassland and Forage Science
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• v.29 no.3
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• pp.179-186
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• 2009

This study was conducted to evaluate yield and forage quality of domestic silage corn hybrids at different planting dates. Days to silking of Suwon169 and P3394 were 62 days, respectively, the shortest among corn hybrids and Gangdaok was the longest. Cheonganok was more resistant to lodging than other hybrids. Kwangpyeongok and Gangdaok were more excellent to stay-green than other hybrids. Ear ratios to total dry matter of other domestic hybrids except Gangdaok were similar with those of DK697 and P3394. Ear ratios to total dry matter were similar in planting dates, May 3 and May 21 with 46% and 45% but June 11, low with 41%. Fresh yield of Gangdaok was the highest of all hybrids and other hybrids except Gangdaok were similar. Dry matter (DM) yields of domestic hybrids except Cheonganok were similar to those of DK697 and P3394. Total digestible nutrients (TDN) yields of domestic hybrids were no significant difference compared with those of DK697 and P3394. Fresh yield, DM yield and TDN yield of all hybrids were similar in planting dates, May 3 and May 21 but those of all hybrids were reduced in planting date, June 11 compared with May 3 and May 21. All hybrids were no significant difference in acid detergent fiber (ADF) which had values ranging from $44.2{\sim}46.2%$. All hybrids were no significant difference in neutral detergent fiber (NDF) which had values ranging from $58.1{\sim}59.9%$. There were no significant differences in ADF and NDF according to planting dates. Relative feed value (RFV) of P3394 was the lowest of all hybrids. Other hybrids except P3394 had values ranging from $84.1{\sim}85.0$ and was no significant difference in RFV. It is concluded that domestic hybrids tested in this study have high forage quality as well as high production similar to those of imported corn hybrids.