• Korean Journal of Organic Agriculture
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• v.23 no.2
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• pp.373-390
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• 2015

This study investigated the effect of coated feed using mixed oil on rumen fermentation characteristics. Two experiments were conducted based on materials that were mixed. First, cashew nut and soybean oils were mixed with white mineral oil. And second, different plant extracts were mixed with white mineral oil. At first experiment, inclusion levels of mixed oil on diet (0.03%, 0.1%, 0.5%) were applied as variables. A coated diet was fermented with rumen inoculum according to in vitro rumen fermentation and its parameters were investigated. In the result of first experiment, no negative effects on rumen pH were found. Significantly decreased dry matter digestibility was detected at 0.5% treatment (P<0.05). Total gas productions in control and 0.03% were significantly greater than those of others (P<0.05). Significantly reduced methane productions were found in all treatments compared to the control (P<0.05). Inclusion of mixed oil did not affect on ammonia production. Total volatile fatty acid production was also not influenced by coating with mixed oils. Rumen fermentation parameters were greatly changed according to introduced plant extracts at second experiment. The significantly lowest and greatest ammonia productions were found at treatments with Ixeris dentata and Plantago asiatica, respectively (P<0.05). The significantly greatest acetate and propionate productions were detected at treatments with Crucuma longa and Zizyphus vulgaris 1, respectively (P<0.05). All treatments, except Chrysanthemum idicum, Euyale ferox seed, Moringa leaf and fruit and Zizyphus vulgaris 1, showed significantly increased total volatile fatty acid production compared to the control (P<0.05). Only Paeonia lactiflora showed significantly lesser gas production than the control (P<0.05). In methane production, Ceramium, Zizyphus, Paeonia, Agrimonia, Torilis, Mugwort, Foeniculum, Euphorbia, Taraxacum, Artemisia, Momordica, Curcuma and Moringa reduced methane significantly compared to the control (P<0.05).

• Journal of Korean Society of Forest Science
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• v.83 no.4
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• pp.505-511
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• 1994

Seeds of Rigitaeda pine tree(Pinus rigida${\times}$P. taeda) was primed with polyethylene glycol(PEG-6000) under different PEG concentrations, treatment period, and temperatures to test uniformity of germination. Coated seeds and PEG treated seeds were sown to compare germination, emergence, establishment, and seedling growth. The results obtained are summarized as follows : 1. As the concentration of PEG increased, as total germination percentage of pine tree was increased. Total germination percentage of pine tree seeds primed with PEG at 15 or $20^{\circ}C$ was better than the seeds treated at $10^{\circ}C$ compared to untreated seeds. 2. Germination rate was improved as primed period long and level of PEG concentration high. 3. Maximum germination rate was high with long PEG treatment period, and markedly improved when the seeds were primed at $20^{\circ}C$ 4. Priming with PEG at $20^{\circ}C$ for 12 days reduced time taken for germination. 5. Osmoconditioned seeds accelerated germination under drought condition with injurious effect of coated seeds by some chemicals. 6. There were much differences in establishment and dry matter production between drill and oversowing method, and primed seeds showed better performances than the coated seeds. Coating effects to seeds were better under drought soil condition rather than moderate moisture condition.

• Membrane Journal
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• v.19 no.4
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• pp.261-267
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• 2009

Polyimide which is the glassy polymer has high chemical resistance, thermal stability and high mechanical property. In this study, the polyimide hollow fiber membranes were prepared by the dry-jet wet phase inversion in order to investigate the permeation porperties of the $H_2S$ and $CH_4$. The morphology of prepared hollow fiber membranes and their permeation behaviors of $H_2S$ and $CH_4$ before and after silicon coating were evaluated. The permeance of $H_2S$ and $H_2S/CH_4$ selectivity increased due to plasticization with increasing the feed pressure. The permeance of KSM03b and selectivity of KSM03d were highest among the three type membranes used this experiments. The permeance decreased but the $H_2S/CH_4$ selectivity increased with increasing the air gap. The permeance reduced after silicon coating. However, the selectivity increased and the selectivity of KSM03d was 275 at 7 atm.

• Korean Chemical Engineering Research
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• v.56 no.6
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• pp.901-908
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• 2018

Graphite is used as a sample anode active material. However, since the maximum theoretical capacity is limited to $372mA\;h\;g^{-1}$, a new anode active material is required for the development of a high capacity lithium ion battery. The maximum theoretical capacity of Si is $4200mA\;h\;g^{-1}$, which is higher than that of graphite. However, it is not suitable for direct application to the anode active material because it has a volume expansion of 400%. In order to minimize the decrease of the discharge capacity due to the volume expansion, the Si was pulverized by the dry method to reduce the mechanical stress and the volume change of the reaction phase, and the change of the volume was suppressed by coating the carbon layers to the particle size controlled Si particles. And carbon fiber is grown like a thread on the particle surface to control secondary volume expansion and improve electrical conductivity. The physical and chemical properties of the materials were measured by XRD, SEM and TEM, and their electrochemical properties were evaluated. In this study, we have investigated the synthesis method that can be used as anode active material by improving cycle characteristics of Si.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.2
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• pp.95-101
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• 2017

In this paper, the sizing removal condition for the pretreatment of composite materials is obtained numerically by applying an image processing algorithm and nickel-plated carbon fiber is fabricated by a dry process method to enhance its electromagnetic shielding performance. Sizings that are wrapped in a polymer type material during the manufacturing of carbon fiber should be removed for dry coating. A numerical value, that is the correlation, can be obtained by determining the regular pattern of the carbon fiber in the image taken by a scanning electron microscope (SEM) after the sizing is removed. The application of the proposed numerical method to the SEM image of the fiber after the sizing is removed with solution, compressed air, solution and compressed air (hybrid), showed that this method of eliminating the sizing is superior to the hybrid method. Then, by spreading the carbon fiber roll with the sizing removed, we were able to produce nickel plated carbon fiber by the roll-to-roll sputtering method. The electromagnetic shielding performance of the fabricated 30, 40 and 100 nickel coated carbon fibers was measured. The Korea Advanced Institute of Science and Technology evaluated the electromagnetic shielding performance of the 100 nickel-coated carbon fiber to have a maximum value of 73.2 (dB) and a minimum value of 66.7 (dB). This is similar to the electromagnetic shielding rate of copper and shows that this material can be used as a cable for EV / HEV automobiles.

• Membrane Journal
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• v.15 no.2
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• pp.147-156
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• 2005

It is well-known that polyethersulfone (PES) has high $CO_2$ selectivity over $N_2\;(or\;CH_4)$ and excellent pressure resistance of $CO_2$ plasticization among muy commercialized engineering plastics[1-4]. Asymmetric PES hollow fiber membranes for flue gas separation were developed by dry-wet spinning technique. The dope solution consists of PES, NMP and acetone. Water and water/NMP mixtures are used in outer and inner coagulants, respectively. Gas permeation rate (i.e., permeance) and $CO_2/N_2$ selectivity were measured with pure gas, respectively and the micro-structure of hollow fiber membranes was characterized by scanning electron microscopy. The effects of polymer concentration, ratio of NMP to acetone, length of air gap, evaporation condition and silicone coating were investigated on the $CO_2/N_2$ separation properties of the hollow fibers. Optimized PES hollow fiber membranes exhibited high permeance of $25\~50$ GPU and $CO_2/N_2$ selectivity of $30\~40$ at room temperature and have the apparent skin layer thickness of about $0.1\;{\mu}m$. The developed PES hollow fiber membranes, would be a good candidate suitable for the flue gas separation process.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.268-268
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• 2017

Common sowing method of italian ryegrass (IRG) has been using the backpack seed sprayer (BSS) in Korea. It has weak point including a hard work and a little sowing area. This study was conducted to find out the effects of sowing IRG using unmanned helicopter (UH) under the established rice field. We checked the labour saving of sowing IRG and the growth and yield of rice after using IRG as forage crop. Two sowing implements(using by UH and backpack seed sprayer (BSS)) were tested for the ability of sowing IRG. For proper pretreatment of IRG seeds for aerial sowing using with UH, we tested one-day soaking seeds, iron-coated seeds, coated seeds sold in stores and untreated seeds. Aerial sowing of IRG seeds using UH was tested under the speed 10 km/h and flying altitude 3~4m. We tried to confirm the effects on rice growth in a paddy field after IRG had been used as forage in mid May. In 6 hours of seeding per day, UH had a seeding area of 21.8 hectares, three times wider than BSS. UH had a decrease of about 63 percent of sowing-seed cost in comparison with BSS. In the IRG aerial sowing using UH, coating seeds had the wider sowing width of 5~6 meter than 3~4 meter untreated seeds. Residual dry matter of IRG after using forage had 4.5 ton per hectare and 20 percent of top dry matter. The amount of nitrogen remaining in residual IRG in the soil was 12 kg per hectare, and the other nutrients such as calcium and potassium was incorporated into the soil with less than 10 kg/ha. The rice yield after the harvesting IRG was 5 percent higher than that of rice single cropping. Consequently, IRG sowing using UH was effective in reducing sowing time and sowing cost compared with conventional methods and, it is considered that there is a positive effect on the rice cultivation compared to rice single cropping.

• Journal of the Korean Vacuum Society
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• v.17 no.3
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• pp.175-182
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• 2008

This study is concerned with the evaluation of the corrosion resistance of coated semiconductor equipment parts with various processes. To select the appropriate basis for evaluation, replacement parts were observed during the semiconductor manufacturing process. This study also ran a dry corrosion test using $Al_2O_3$, which is mostly used as a coating material. This test quantitatively measured the efficiency of coated parts. Surface morphology, leakage current and breakdown voltage were also evaluated. This study showed that a dry corrosion process led to the drop of electrical properties, for example, the leakage current increase and the dielectric strength decrease. The surface morphology test displayed that surface damage is largely dependent on the exposure time to corrosive environments. By using the values that changed during the corrosion process, it may be possible to contrive a method to evaluate the efficiency of coated parts with various processes.

• Korean Journal of Weed Science
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• v.12 no.3
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• pp.200-222
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• 1992

The results of recent researches for improvement of seedling stand in direct seeded rice on the dry paddy in Korea were summarized as the following ; a variety to be cultivated should be chosen the characteristics of high percentage germination under low temperature, shorter period of shoot emergence, and better growth of the mesocotyl and shoots. Meanwhile, there was 40% increase in seedling stand at the treatment of removal of the seed awn under using the drill seeder. After seeding the rice seed covered with soil of 3cm depth was better seedling emergence and also there was the hightest seedling emergence at the 70% of moisture content of the soil. In addition, the application of the Release containing GA 10% enabled to increase the seedling stand and furthermore it was effective under deep seeding depth. The optimum seeding date should be seeded around May 10 when mean air temperature is above 12-13$^{\circ}C$ so that may establish more less 70% in seedling stand. Based on an appropriate seedling stand of 150/$m^2$, the optimum seeding rate was 5kg/10a. It was the best in seeding method using drill seeder and the most desirable recommended seeding method was the drill seeder in terms of seedling stand. In order to improve seedling stand water management was more effective in canal irrigation and in drainage at 6hr after irrigation following by the seeding process. On the other hand, for the increase of seedling stand under flooded condition a variety might have characters being better germination at low concentration of dissolved oxygen and vertically deeper growing of the crown root. Also, seedling stand was able to increase with the seed coating of $CaO_2$in the flooded soil. It was possible to be seeded on the early part of May being mean air temperature of avove 10$^{\circ}C$ and the optimum seeding rate was 5kg/10a. For an effective water management water would be flooded up to 3cm depth for 2-3 weeks after seeding. The rice plant grown under the direct seeded cultivation might be not so much strong in lodging resistance compared to that grown under the transplanting and moreover direct seeded rice cultivation under flooded condition would be more weak growth of the rice plant than that on dry paddy. Meanwhile, the lodging would be affected by the seeding rate, the soil depth after seeding. and seeding method even in the same variety. In particular, roots in the lodging pattern of direct seeded rice cultivation under flooded condition were largely distributed on the soil surface so that resulted easily in the lodging. In general, the lodging resistance would be greater as seeding rate and amount of N fertilizer application are lower and soil depth after seeding is higher. Among the introduction of different seeding method the high ridged drill seeding method on dry paddy soil resulted in the lowest in the lodging index and also it was lower in the drill seeding method than in the scattering seeding method under flooded condition. In case of more than 150 seedlings per $m^2$ there was a severe lodging due to high lodging index at the 3rd and 4th internodes. The effective lodging prevention was able to at the treatment of the Inabenfide at 45 days before heading and the Uniconazol at 15 days before heading which caused the shortage by 10-15cm in culm length. Also, fertilizer management using split application of nitrogen would be contributed the reduction of lodging at the rate of 20-30-20-20-10%(basal-5th leaf stage-7th leaf stage-panicle initiation stage-heading stage) on the dry paddy soil.

• Proceedings of the Korean Vacuum Society Conference
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• 2012.08a
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• pp.393-393
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• 2012

Optically active nanostructures such as subwavelength moth-eye antireflective structures or surface enhanced Raman spectroscopy (SERS) active structures have been demonstrated to provide the effective suppression of unwanted reflections as in subwavelength structure (SWS) or effective enhancement of selective signals as in SERS. While various nanopatterning techniques such as photolithography, electron-beam lithography, wafer level nanoimprinting lithography, and interference lithography can be employed to fabricate these nanostructures, roll-to-roll (R2R) nanoimprinting is gaining interests due to its low cost, continuous, and scalable process. R2R nanoimprinting requires a master to produce a stamp that can be wrapped around a quartz roller for repeated nanoimprinting process. Among many possibilities, two different types of mask can be employed to fabricate optically active nanostructures. One is self-assembled Au nanoparticles on Si substrate by depositing Au film with sputtering followed by annealing process. The other is monolayer silica particles dissolved in ethanol spread on the wafer by spin-coating method. The process is optimized by considering the density of Au and silica nano particles, depth and shape of the patterns. The depth of the pattern can be controlled with dry etch process using reactive ion etching (RIE) with the mixture of SF6 and CHF3. The resultant nanostructures are characterized for their reflectance using UV-Vis-NIR spectrophotometer (Agilent technology, Cary 5000) and for surface morphology using scanning electron microscope (SEM, JEOL JSM-7100F). Once optimized, these optically active nanostructures can be used to replicate with roll-to-roll process or soft lithography for various applications including displays, solar cells, and biosensors.