• Proceedings of the Materials Research Society of Korea Conference
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• 2011.05a
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• pp.5-5
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• 2011

The research and development of hybrid electric vehicle (HEV), plug-in hybrid electric vehicle (PHEV) and electric vehicle (EV) are intensified due to the energy crisis and environmental concerns. In order to meet the challenging requirements of powering HEV, PHEV and EV, the current lithium battery technology needs to be significantly improved in terms of the cost, safety, power and energy density, as well as the calendar and cycle life. One new technology being developed is the utilization of composite cathode by mixing two different types of insertion compounds [e.g., spinel $LiMn_2O_4$ and layered $LiMO_2$ (M=Ni, Co, and Mn)]. Recently, some studies on mixing two different types of cathode materials to make a composite cathode have been reported, which were aimed at reducing cost and improving self-discharge. Numata et al. reported that when stored in a sealed can together with electrolyte at $80^{\circ}C$ for 10 days, the concentrations of both HF and $Mn^{2+}$ were lower in the can containing $LiMn_2O_4$ blended with $LiNi_{0.8}Co_{0.2}O_2$ than that containing $LiMn_2O_4$ only. That reports clearly showed that this blending technique can prevent the decline in capacity caused by cycling or storage at elevated temperatures. However, not much work has been reported on the charge-discharge characteristics and related structural phase transitions for these composite cathodes. In this presentation, we will report our in situ x-ray diffraction studies on this mixed composite cathode material during charge-discharge cycling. The mixed cathodes were incorporated into in situ XRD cells with a Li foil anode, a Celgard separator, and a 1M $LiPF_6$ electrolyte in a 1 : 1 EC : DMC solvent (LP 30 from EM Industries, Inc.). For in situ XRD cell, Mylar windows were used as has been described in detail elsewhere. All of these in situ XRD spectra were collected on beam line X18A at National Synchrotron Light Source (NSLS) at Brookhaven National Laboratory using two different detectors. One is a conventional scintillation detector with data collection at 0.02 degree in two theta angle for each step. The other is a wide angle position sensitive detector (PSD). The wavelengths used were 1.1950 ${\AA}$ for the scintillation detector and 0.9999 A for the PSD. The newly installed PSD at beam line X18A of NSLS can collect XRD patterns as short as a few minutes covering $90^{\circ}$ of two theta angles simultaneously with good signal to noise ratio. It significantly reduced the data collection time for each scan, giving us a great advantage in studying the phase transition in real time. The two theta angles of all the XRD spectra presented in this paper have been recalculated and converted to corresponding angles for ${\lambda}=1.54\;{\AA}$, which is the wavelength of conventional x-ray tube source with Cu-$k{\alpha}$ radiation, for easy comparison with data in other literatures. The structural changes of the composite cathode made by mixing spinel $LiMn_2O_4$ and layered $Li-Ni_{1/3}Co_{1/3}Mn_{1/3}O_2$ in 1 : 1 wt% in both Li-half and Li-ion cells during charge/discharge are studied by in situ XRD. During the first charge up to ~5.2 V vs. $Li/Li^+$, the in situ XRD spectra for the composite cathode in the Li-half cell track the structural changes of each component. At the early stage of charge, the lithium extraction takes place in the $LiNi_{1/3}Co_{1/3}Mn_{1/3}O_2$ component only. When the cell voltage reaches at ~4.0 V vs. $Li/Li^+$, lithium extraction from the spinel $LiMn_2O_4$ component starts and becomes the major contributor for the cell capacity due to the higher rate capability of $LiMn_2O_4$. When the voltage passed 4.3 V, the major structural changes are from the $LiNi_{1/3}Co_{1/3}Mn_{1/3}O_2$ component, while the $LiMn_2O_4$ component is almost unchanged. In the Li-ion cell using a MCMB anode and a composite cathode cycled between 2.5 V and 4.2 V, the structural changes are dominated by the spinel $LiMn_2O_4$ component, with much less changes in the layered $LiNi_{1/3}Co_{1/3}Mn_{1/3}O_2$ component, comparing with the Li-half cell results. These results give us valuable information about the structural changes relating to the contributions of each individual component to the cell capacity at certain charge/discharge state, which are helpful in designing and optimizing the composite cathode using spinel- and layered-type materials for Li-ion battery research. More detailed discussion will be presented at the meeting.

• Korean Journal of Soil Science and Fertilizer
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• v.29 no.3
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• pp.207-211
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• 1996

This study was conducted in the sandy loam soil to find out the effects of fly ash and zeolite applications on saving of irrigation water which was required great quantities during the cultivation days of dry seeded rice. Total water loss was reduced so rapidly in the early growth stage that n was the least in the 18th day after irrigation. After that day it was increasd due to the growth development and the rising temperature. In the daily mean of decreasing water level during the whole irrigation days, control was 47.7mm but the treatments of fly ash and zeolite were 31.8mm and 35.8mm respectively Amounts of the presumed irrigation water of fly ash and zeolite treatments were lower about 29.1% and 20.9%. respectively than that of control during the whole irrigation days These gaps between control and amendment treatments were greater in the early growth stage than in the late stage Hardness, bulk density and the ratio of solid phase in the soil after experiment were the highest in the fly ash treatment and those of control and zeolite treatments were showed the same trends each other. Amounts of water percoration of control and zeolite treatments in the soil were increased 8.2% and 2.6% respectively in comparision with those in the soil after amendment application, but that of fly ash treatment was decreased 42.5%, In contrast to the water percoration of control in the soil after experiment, those of fly ash and zeolite treatments were decreased 76% and 32%.

• Korean Journal of Soil Science and Fertilizer
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• v.45 no.5
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• pp.744-748
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• 2012

This study was carried out to investigate the incorporation effect of green manure crops (GMC) such as the hairy vetch on improvement of soil environment in reclaimed land during sorghum${\times}$sudangrass hybrid (SSH) cultivation over the past three years from 2009 to 2011. Plots consisted of conventional fertilization (CF) and incorporation of GMC were divided by rates of additional nitrogen fertilizer ($100kg\;ha^{-1}$) and decreased percentage of 30 50 70 100 fertilization in addition to non nitrogen fertilization (NNF). Soil physico-chemical properties, growth and yield potential were examined. The results were as follows. The testing soil was showed strong alkaline saline soil with low organic matter contents and less available phosphate while exchangeable sodium and magnesium were higher. Soil salinity was increased during cultivation of summer crop. However, SSH was not affected by salt content. The fresh weight of GMC at incorporation time was $18,345kg\;ha^{-1}$. Content of total nitrogen at incorporation time was 3.09% and the C/N ratio was 12.8. Fresh and dry matter yield of SSH were higher in the order of 30%, CF, N50%, N70%d, N100%, and NNF. Fresh and dry matter yield of SSH increased in the order of CF ($55,050kg\;ha^{-1}$, $16,250kg\;ha^{-1}$), N contents from 30% to 9%. Soil physical properties, such as bulk density were decrease with incoporation of GMC, while porosity was increased. Soil chemical properties, such as pH was decreased while content of exchangeable calcium, available phosphate, and organic matter were increased. Also contents of exchangeable sodium and potassium were decreased with incorporation of GMC than those before experiment. Thus, we assumed that incorporation of hairy vetch was more effective that can lead to reduce chemical nitrogen fertilizer and to improve soil environment in cultivating SSH on Saemangeum reclaimed land.

• Korean Journal of Soil Science and Fertilizer
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• v.42 no.4
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• pp.289-300
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• 2009

Flora distribution was surveyed in the newly reclaimed tidal flats in the west coastal area in Korea to understand changes in flora dynamics after reclamation. The surveyed reclaimed tidal flats were the newly reclaimed tidal flat in Hangdam, the mid Kyonggi Bay in 2002, and three reclaimed lands in Seukmun and Daeho, Chungnam, and Hangdam in Kyonggi Bay, of which reclamation years based on embankment were 7, 9 and 18 years, respectively. In the newly reclaimed tidal flat, the dominant flora was Suaeda japonica and other florae were rare, while various halophytes and glycophytes were distributed in the reclaimed lands. On the newly reclaimed tidal flat, four species of halophytic pioneer florae, Salicornia europaea, Suaeda glauca, Suaeda japonica, and Suaeda maritime occurred, and along with age facultative halophyte and glycophyte occurred sequently. On the reclaimed lands, the florae were more complex with various facultative halophyte and glycophyte, so these were predominated rather than pioneer halophyte, while one of pioneer halophyte that Suaeda japonica was not occurred. Increasing of various facultative halophyte and glycophyte, and decreasing of pioneer halophyte indicated that flora changed toward to increase of facultative halophyte and glycophyte by aged after reclamation. On the newly reclaimed tidal flat the ratio of flora species changed rapidly with the invasion of plant. This implied that the flora had begun to change in the early stage of reclamation. Facultative halophyte and glycophyte started to increase on the early stage of reclamation but relative density and frequency of pioneer halophyte was higher than facultative halophyte and glycophyte. According to the investigation up to 3 years after reclamation, pioneer halophyte predominated on it. Although flora changed, there were common representative halophytes among the reclaimed tidal flats: Salicornia europaea, Suaeda maritima, and Suaeda glauca as pioneer halophyte, Aster tripolium, Sonchus brachyotus, and Phragmites communis as facultative halophytes.

• Korean Journal of Medicinal Crop Science
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• v.3 no.2
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• pp.140-145
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• 1995

This experiment was carried out to investigate the effect of plant spacing on the growth and root yield at different harvesting year in Astragalus membranceus. A local variety collected in Jung Sun. Kang Won was used on the 30 and 40cm row spacing, with different spacing between plant of 5, 10, 15, 20cm respectively. Nitrogen, phosphorus and potassium fertilizers were applied as 6, 8 and 9kg/10a respectively, with compost of 1,000kg/10a. Branches, root length, root diameter and root weight were increased in the sparse planting compared with the dense planting. But emergence date, flowering date, stem height and node number were not significantly changed with plant spacing. The highest root yield was 211.8kg/10a at the $30{\time}10cm(67\;plants/m^2)$ in 1 year old plants of Astragalus membranceus. In case of two years old plants, branches, node number, root length, root diameter and root weight were increased in the sparse planting compared to the dense planting. But harvesting ratio was decreased in the dense planting, The highest dried root yield was 292kg/10a at the $40{\time}10cm\;(25\;Plants/m^2)$. In case of 3 years old plants, aerial part and root growth pattern were similar to the 2 years old plants, The dried root yield was highest(623kg/10a) in the $40{\time}10cm(25plants/m^2)$.

• Korean Journal of Agricultural Science
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• v.42 no.1
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• pp.37-46
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• 2015

This study was carried out to determine the effect of storage condition, such as temperature and relative humidity (RH), on the change of sensory properties and free fatty acid composition of pre-packed Hanwoo loin (Musculus longissimus) until $21^{st}$ day of storage. The Hanwoo loin was sliced in $1.0{\pm}0.2cm$ thickness and each of the sliced pieces was packed in a foamed polystyrene tray with linear low-density polyethylene (LLD-PE) film to simulate the pre-packed Hanwoo loin sold in retail market, then stored in home-style refrigerator (Con; $5^{\circ}C$, 17%RH), and temperature and RH controled chambers (T1; $5^{\circ}C$, 55%RH, T2; $5^{\circ}C$, 85%RH, and T3; $-1^{\circ}C$, 99%RH), respectively. The sensory characteristics of pre-packed Hanwoo loin during storage in different conditions were measured on raw or after cooking. After 21 days of storage, the loin stored in T3 showed significantly high color and acceptability scores ($7.46{\pm}1.07$, $7.06{\pm}1.36$, respectively) on raw loin, and flavor and acceptability scores ($7.16{\pm}0.90$, $6.90{\pm}0.92$, respectively) on cooked loin than those of others (p<0.05). The concentration of 12 fatty acids of pre-packed Hanwoo loin during storage in different conditions were analysed. The concentration of oleic acid (C18:1, $39.92{\pm}3.22%$), palmitic acid (C16:0, $28.20{\pm}2.42%$), and stearic acid (C18:0, $12.59{\pm}2.79%$) was high in Hanwoo loin on $1^{st}$ day of storage. The concentration of palmitic acid of Hanwoo loin stored in T2 was increased significantly after $4^{th}$ day of storage (p<0.05), and the concentration of myristic acid(C14:0) of Hanwoo loin stored in treated chamber (T1 to T3) was significantly higher than Con after $14^{th}$ day of storage (p<0.05). The concentration of linolenic acid (C18:3) of Hanwoo loin was decreased significantly after $4^{th}$ day of storage in all tested storage conditions (p<0.05). However, there was no significant or consistent change in the concentration of oleic acid (C18:1) during storage period in every Hanwoo loin stored in tested conditions. Although, the concentration of total monounsaturated fatty acids (MUFA) was decreased in Con and T2 (p<0.05), there was no consistent change in the monounsaturated fatty acids to saturated fatty acids ratio (MUFA/SFA) during storage period (p>0.05). From those results, it was considered that storage condition affects on the sensory acceptability and fatty acid composition of pre-packed Hanwoo loin as storage period was increased.

• Geophysics and Geophysical Exploration
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• v.9 no.1
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• pp.60-66
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• 2006

Three differing sandstones, two synthetic and one field sample, have been tested ultrasonically under a range of confining pressures and pore pressures representative of in-situ reservoir pressures. These sandstones include: a synthetic sandstone with calcite intergranular cement produced using the CSIRO Calcite In-situ Precipitation Process (CIPS); a synthetic sandstone with silica intergranular cement; and a core sample from the Otway Basin Waarre Formation, Boggy Creek 1 well, from the target lithology for a trial $CO_2$ pilot project. Initial testing was carried on the cores at "room-dried" conditions, with confining pressures up to 65 MPa in steps of 5 MPa. All cores were then flooded with $CO_2$, initially in the gas phase at 6 MPa, $22^{\circ}C$, then with liquid-phase $CO_2$ at a temperature of $22^{\circ}C$ and pressures from 7 MPa to 17 MPa in steps of 5 MPa. Confining pressures varied from 10 MPa to 65 MPa. Ultrasonic waveforms for both P- and S-waves were recorded at each effective pressure increment. Velocity versus effective pressure responses were calculated from the experimental data for both P- and S-waves. Attenuations $(1/Q_p)$ were calculated from the waveform data using spectral ratio methods. Theoretical calculations of velocity as a function of effective pressure for each sandstone were made using the $CO_2$ pressure-density and $CO_2$ bulk modulus-pressure phase diagrams and Gassmann effective medium theory. Flooding the cores with gaseous phase $CO_2$ produced negligible change in velocity-effective stress relationships compared to the dry state (air saturated). Flooding with liquid-phase $CO_2$ at various pore pressures lowered velocities by approximately 8% on average compared to the air-saturated state. Attenuations increased with liquid-phase $CO_2$ flooding compared to the air-saturated case. Experimental data agreed with the Gassmann calculations at high effective pressures. The "critical" effective pressure, at which agreement with theory occurred, varied with sandstone type. Discrepancies are thought to be due to differing micro-crack populations in the microstructure of each sandstone type. The agreement with theory at high effective pressures is significant and gives some confidence in predicting seismic behaviour under field conditions when $CO_2$ is injected.

• Geophysics and Geophysical Exploration
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• v.10 no.1
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• pp.98-109
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• 2007

Over the last twenty years, farmers in Western Australia have begun to change land management practices to minimise the effects of salinity to agricultural land. A farm plan is often used as a guide to implement changes. Most plans are based on minimal data and an understanding of only surface water flow. Thus farm plans do not effectively address the processes that lead to land salinisation. A project at Broomehill in the south-west of Western Australia applied an approach using a large suite of geospatial data that measured surface and subsurface characteristics of the regolith. In addition, other data were acquired, such as information about the climate and the agricultural history. Fundamental to the approach was the collection of airborne geophysical data over the study area. This included radiometric data reflecting soils, magnetic data reflecting bedrock geology, and SALTMAP electromagnetic data reflecting regolith thickness and conductivity. When interpreted, these datasets added paddock-scale information of geology and hydrogeology to the other datasets, in order to make on-farm and in-paddock decisions relating directly to the mechanisms driving the salinising process. The location and design of surface-water management structures such as grade banks and seepage interceptor banks was significantly influenced by the information derived from the airborne geophysical data. To evaluate the effectiveness ofthis planning., one whole-farm plan has been monitored by the Department of Agriculture and the farmer since 1996. The implemented plan shows a positive cost-benefit ratio, and the farm is now in the top 5% of farms in its regional productivity benchmarking group. The main influence of the airborne geophysical data on the farm plan was on the location of earthworks and revegetation proposals. There had to be a hydrological or hydrogeological justification, based on the site-specific data, for any infrastructure proposal. This approach reduced the spatial density of proposed works compared to other farm plans not guided by site-specific hydrogeological information.

• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.10
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• pp.1294-1300
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• 2008

Nelumbo nucifera G. tea white breads were prepared by the addition of 0.01, 0.02, 0.03, and 0.04% hemicellulase to flour of the basic formulation. The experiments and control were then compared in terms of quality characteristics, including pH, total titratable acidity, fermentation power of dough expansion, specific volume, baking loss, moisture content, color, textural characteristics, external and internal surface appearances, and sensory qualities in order to determine the optimal ratio of hemicellulase in the formulation. There were no significant differences in pH and total titratable acidity of dough among the experiments. Fermentation power of dough expansion were increased as incubation time increased. Baking loss was the highest at the 0.04% addition level, while the lowest at the 0.01% level. As hemicellulase content increased, pH, hardness, and fracturability of bread decreased, while total titratable acidity, specific volume, and resilience increased. Water content and lightness were the highest in the control bread samples, and yellowness was maximal in the 0.01% group. Bread made by the addition of hemicellulase had significantly higher greenness and flavor than the control group. Color, consistency, and springiness of crumb, density and uniformity of crumb pore, softness, chewiness, overall acceptability, lotus leaf flavor, delicious taste, astringency, bitterness, and off-flavor were not significantly different among the samples. The results indicate that adding 0.02$\sim$ 0.03% hemicellulase in N elumbo nucifera G. tea white bread is optimal for quality and provides a product with reasonably high overall acceptability.

• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.5
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• pp.625-632
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• 2008

Rye-wheat mixed bread samples made with substitutions of 20, 40, 60 and 80% sourdough, and control made with the addition of naturally fermented raisin extract, were examined for quality characteristics such as pH, total titratable acidity, fermentation power of dough expansion, specific volume, baking loss, water activity, color, texture, external and internal surface appearance, and sensory qualities, in order to determine the optimal ratio of sourdough in the formulation. As the incubation time of sourdough increased, pH decreased, while total titratable acidity increased. The pH of rye-wheat mixed doughs decreased with increasing sourdough content, but total titratable acidity increased. The rye-wheat mixed breads prepared with substitutions of sourdough had higher pH and lower total titratable acidity than the control group. Fermentation power of dough expansion of rye-wheat mixed doughs increased with increasing incubation time. Specific volume was maximum on the 20% substitution sourdough. Baking loss was inferior with the 80% substitution sourdough. Water activity and lightness was minimum on the control group. The higher amounts of sourdough showed the higher tendency of lightness, redness and yellowness. In the texture characteristics, hardness, gumminess, and chewiness was minimum on the control group and tended to increase with higher substitution of sourdough. Substitution of sourdough showed decrease adhesiveness. Fracturability, cohesiveness, and resilience of all rye-wheat mixed breads were not significantly different. Springiness was maximum on the 20% substitution sourdough and minimum on the 40%. A side of loaf of rye-wheat mixed breads, except for 20%, had a poor break and shred. In sensory evaluation, as substitution amount of sourdough increased, the scores of color and consistency of crumb, uniformity of crumb pore, gumminess, and overall acceptability decreased; while the density of crumb pore, springiness of crumb, aroma of rye flour, sourness, and bitterness showed the reverse effect; the 20, 40, and 60% sourdough samples obtained fairly good scores. In conclusion, these results indicated that $20{\sim}60%$ of sourdough could be very useful as a substitute for baker's yeast in developing rye-wheat mixed bread.