• Journal of the Korean earth science society
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• v.23 no.8
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• pp.697-706
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• 2002

Authigenic siderite grains, ranging 100 to 250-${\mu}$m in diameter, are abundant in an about 8,600-year-old sediment layer in Namyang Bay, west coast of Korea. The siderites exhibit the aggregated spherulitic morphology with well-developed rhombs on the grain surfaces. They consist mostly of FeCO$_3$ (average, 65%) and MnCO$_3$ (average, 22%) with low Mg/Ca ratio (less than 0.4) in their bulk composition. A series of compositional ternary discrimination diagrams, together with high Mn and low Mg contents, show that only meteoric porewater was involved in siderite precipitation, assuming that depositional environment of host sediment is an organic-rich freshwater system. Considering a series of results such as radiocarbon age, authigenic Mn-rich siderite and lithological features, siderite-hosting sediment (unit Tl) is interpreted as freshwater swamp or bog deposition, infilling the topographic depressions that locally existed before the formation of mid-to-late Holocene tidal deposits. Center-to-margin compositional variation within individual grain is very systematic; Mn and Ca decrease towards the margin of a siderite grain, while Fe and Mg increase. It suggests that the spherulitic siderites were precipitated in this sedimentary layer in a series during the early diagenesis of MnOx-FeOx reduction under steady-state.

• Research in Plant Disease
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• v.10 no.3
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• pp.167-174
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• 2004

To make the forecasting model of rice bacterial grain rot (RGBR) using the statistical procedures with SAS(Statistical Analysis System) based on micro-weather factors during heading period of rice, 21 rice varieties having the different heading time (40％ panicles headed) were planted at 30 May and 15 June in Naju. Heading time and diseased panicles were investigated from July to August in 1998. RGBR mainly occurred on varieties headed from 29 July to 19 August, but not on varieties headed after 22 August. RGBR was highly correlated with diurnal temperature during 7 days (r =-0.871 **) and 10 days (r =-0.867**) and minimum relative humidity during 15 days from 3 days before heading time. After examining the models with several ways ($R^2$, Adjusted $R^2$, MSE), one equations were selected： Y =92.83 - 2.43Tavr + 1.88Tmin - 1.04RHavr + 0.37RHmin + 0.43RD - 3.68WS ($R^2$=0.824) using six variables of average and minimum temperature (Tavr and Tmin), average and minimum relative humidity (RHavr and RHmin), rainy days (RD), and wind speed (WS) during 7 days from 3 days before to 3 days after heading time.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.36 no.1
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• pp.17-21
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• 1991

The study was performed to investigate the effects of gaseous emission of sulfur dioxide and hydrogen fluoride on the growth of rice plant under stressed field conditions. This study is specifically dealt with multiple effects of sulfur dioxide and hydrogen fluoride on various plant growth indicators such as leaf damage, weight of grain, panicles per hill, spikelets per panicle and percent fertility. It appears that there is a good correlation between ambient concentrations of sulfur oxides and sulfur contents found in leaves with an average correlation coefficient of 0.868 within a 1% significance level. A better multiple correlation was found between percent leaf damage and sulfur and fluorine contents found in leaf with a significance of 1% level. The correlation coefficient ranges from 0.807 to 0.978 with an average being 0.922. An evaluation of data observed has demonstrated that both panicles per hill and percent fertility are significantly affected by air pollutants. As expected, hydrogen fluorides have more effects than sulfur oxides. It is, however, interesting to note that spikelets per panicle has slightly been affected while no indication of effects on l000-grain weight has been observed. This may lead to a conclusion that a reduction in yield of rice under polluted field conditions may have more been caused by the diminution panicles per hill and percent fertility rather than by the diminution of spikelets per panicle and grain weight.

• Journal of the Korean Magnetics Society
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• v.1 no.1
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• pp.12-16
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• 1991

The effect of annealing on the magnetic properties and the microstructures of the amorphous $Fe_{76-x}Cu_1Mo_xSi_{14}B_9$(x=2,3) alloys were investigated. When annealed at 500${^{\circ}C}$ for 1hr, $8{\sim}9{\times}10^3$ of the effective permeability and 3~4 A/m of the coercive force were achieved upon crystallization to $\alpha$-Fe phase. And the average diameter of the $\alpha$-Fe grains was about 20nm. For the nanovrystalline ferromagnets. the fine grain size is the important requirement to obtain a good soft magnetic property. In this work, in order to get the finer grain size of $\alpha$-Fe phase, two-step annealing treatment was given. That is, following the low-temperature at $400{^{\circ}C}$ for 1~3hr, the high-temperature annealing at $500{^{\circ}C}$ for 1hr was carried out. As the low-temperature annealing time increased, the effective permeability increased to $1.2{\sim}1.7{\times}10^4$ and the coercive force decreased to about 2 A/m. And the grain size was observed to be smaller than 10nm. The increased permeability and the decreased coercive force were attributed to the reduced average crystalline anisotropy by the refinement of $\alpha$-Fe(Si) grains.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.254-254
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• 2017

This study evaluated the grain quality of local brand rice from 6 major rice exporting countries which are anticipated to export their rice to Korea. Recently, with the end of the postponement of rice import tariffs in 2014, Korea is in a very easy environment to import foreign rice. Therefore, the quality evaluation of local brand rice in those countries is needed to secure the quality competitiveness of Korean rice, also to protect the rice industry in Korea. We provided total 38 local brand rice from USA(7), China(16), Australia(4), Thailand(3), Vietnam(5) and India(3), and 2 imported brand rice through MMA from USA and China to find out the status of the grain quality for each country. For the quality evaluation, we analyzed the physicochemical properties, milling and palatability-related characteristics. The amylose content on country average ranged from 24.4(India)~16.2%(Thailand). The protein content was 6.66% by overall average, and was higher in order of India(7.86), Australia(6.80), Vietnam(6.61), Thailand(6.59), China(6.28), USA(5.82). In Toyo glossiness value, it ranged from 75.7~45.2, and the figures in USA and China were the highest level. The head rice ratio ranged from 95.2~72.4%, and the figures in Thailand, USA and China were distinctly high. When we analyze the palatability of boiled brand rice with Chucheongbyeo as check variety by expert panelists, several rice brands from USA and China showed equal or better scores in shape, smell, taste, stickiness, texture and overall score, although most rice brands showed a tendency to decrease significantly in the taste characteristics compared with Chucheongbyeo. From the above results, it can be seen that the grain quality of USA and China rice is very competitive when imported into Korea. The results will provide basic information for the quality control of foreign rice which will be imported into Korea in the near future, also for the quality information which could be applied on the development of high-quality Korean rice varieties. Continuous monitoring about the foreign brand rice is advisable to improve the quality competitiveness of Korean rice.

• Asian-Australasian Journal of Animal Sciences
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• v.10 no.6
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• pp.635-642
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• 1997

This experiment was conducted to determine apparent ileal and fecal digestibilities of some grains for young pigs (15.6 kg BW). Ileal and fecal digestibility of corn, milo, wheat, barley, rice and tapioca were measured with pigs fitted with simple ileal T-cannula. Rice was the highest (p < 0.05) and tapioca was the lowest (p < 0.05) in the digestibilities of gross energy. For the crude protein digestibilities, rice, barley and wheat were higher (p < 0.05) than corn, milo and tapioca. The average ileal digestibilities of essential amino acids (AAs) were 89.9, 85.8, 81.5, 80.9, 80.2 and 76.3% for those fed rice, barley, milo, wheat, corn and tapioca diets, respectively. Regardless of the dietary carbohydrate sources, among the dispensable amino acids, glycine had lowest digestibility except for barley and milo. The apparent ileal digestibility of lysine and methionine were 90.7, 94.0% in rice, 88.3, 86.5% in barley and 86.3, 82.3% in wheat. The apparent fecal digestibility of average essential AAs were 90.8, 89.9, 87.7, 85.1, 82.5 and 77.9% in pigs fed the rice, barley, wheat, corn, milo and tapioca diets, respectively. The fecal digestibilities of essential AAs and nonessential AAs, in general, were higher than the ileal digestibilities, which indicating a loss of nitrogenous components in the cecum and colon. For all AAs, differences between ileal and fecal amino acid digestibilities ranged from 0.0 (valine) to 5.8 (threonine) in rice, 0.1 (arginine) to 14.5 (glycine) in barley, 2.8 (lysine) to 12.4 (glycine) in wheat, 1.0 (isoleucine) to 12.9 (glycine) in corn, 0.2 (serine, glutamic acid) to 6.5 (methionine) in milo and 0.5 (valine) to 22.1 (glycine) percentage units in tapioca diets. In conclusion, whether it is ileal or fecal, rice and barley appeared to be excellent alternative carbohydrate sources for young pigs in terms of AAs digestibility. However, energy value and cost for each grain should be considered when formulating diets.

• The Journal of the Petrological Society of Korea
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• v.26 no.1
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• pp.1-11
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• 2017

We have dated the K-Ar, Ar-Ar and U-Pb ages of the Masan hornblende-biotite granite in the southern Cretaceous Gyeongsang basin to constrain its emplacement age. The ~108 Ma hornblende K-Ar age obtained in the study is similar to the previously reported Rb-Sr age. However, the single grain total fusion $^{40}Ar/^{39}Ar$ dating on hornblende failed to yield statistically meaningful ages because the isotopic system was open during its alteration. Thus the hornblende K-Ar age in the study is also unlikely to be reliable. The single grain total fusion $^{40}Ar/^{39}Ar$ dating on biotite yielded an average age of $75.8{\pm}3.0Ma$. Apart from scattered data in the range of ~45-75 Ma, the average age increased to ~80 Ma. The SHRIMP and LA-MC-ICPMS U-Pb isotopic compositions of zircon from the Masan hornblende-biotite granite yielded its emplacement age as $87.6{\pm}2.7Ma$ and $86.8{\pm}0.4Ma$, respectively. It is thus likely that the ~80 Ma $^{40}Ar/^{39}Ar$ age of biotite might reflect the cooling age of Masan hornblende-biotite granite or the thermal influences from later intense igneous activities in the Gyeongsang basin.

• Korean Journal of Materials Research
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• v.9 no.10
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• pp.956-961
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• 1999

When the 0-2 mol% of $\textrm{La}_{3+}$ were added to the nanocrystalline $BaTiO_3$ powders and sintered at $1200~1400^{\circ}C$, the nanocrystailine $BaTiO_3$ ceramics having the average grain size of 110-240 nm were obtained except for when no $\textrm{La}_{3+}$ was added and sintered at > $1350^{\circ}C$. As the average grain size decreased from 240 nm to 110 nm, the tetragonality (c/a) and volume fraction of the $90^{\circ}$ domain decreased, and all the properties such as relative dielectric constant at room temperature, maximum relative dielectric constant at the temperature of phase transformation $\textrm{T}_{c}$ and diffuseness of phase transformation at $\textrm{T}_{c}$ also decreased. The results were attributed to the internal stress induced by inhibition of the $90^{\circ}$ domain formation in the case of finer grain size.

• Proceedings of the Korean Journal of Food and Nutrition Conference
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• 2001.12a
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• pp.39-74
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• 2001

The endeavors enhancing the grain quality of high-yielding japonica rice were steadily continued during 1980s∼1990s along with the self-sufficiency of rice production and the increasing demands of high-quality rices. During this time, considerably great, progress and success was obtained in development of high-quality japonica cultivars and qualify evaluation techniques including the elucidation of interrelationship between the physicochemical properties of rice grain and the physical or palatability components of cooked rice. In 1990s, some high-quality japonica rice caltivars and special rices adaptable for food processing such as large kernel, chalky endosperm aromatic and colored rices were developed and its objective preference and utility was also examined by a palatability meter, rapid-visco analyzer and texture analyzer. The water uptake rate and the maximum water absorption ratio showed significantly negative correlations with the K/Mg ratio and alkali digestion value(ADV) of milled rice. The rice materials showing the higher amount of hot water absorption exhibited the larger volume expansion of cooked rice. The harder rices with lower moisture content revealed the higher rate of water uptake at twenty minutes after soaking and the higher ratio of maximum water uptake under the room temperature condition. These water uptake characteristics were not associated with the protein and amylose contents of milled rice and the palatability of cooked rice. The water/rice ratio (in w/w basis) for optimum cooking was averaged to 1.52 in dry milled rices (12% wet basis) with varietal range from 1.45 to 1.61 and the expansion ratio of milled rice after proper boiling was average to 2.63(in v/v basis). The major physicochemical components of rice grain associated with the palatability of cooked rice were examined using japonica rice materials showing narrow varietal variation in grain size and shape, alkali digestibility, gel consistency, amylose and protein contents, but considerable difference in appearance and torture of cooked rice. The glossiness or gross palatability score of cooked rice were closely associated with the peak. hot paste and consistency viscosities of viscogram with year difference. The high-quality rice variety “Ilpumbyeo” showed less portion of amylose on the outer layer of milled rice grain and less and slower change in iodine blue value of extracted paste during twenty minutes of boiling. This highly palatable rice also exhibited very fine net structure in outer layer and fine-spongy and well-swollen shape of gelatinized starch granules in inner layer and core of cooked rice kernel compared with the poor palatable rice through image of scanning electronic mcroscope. Gross sensory score of cooked rice could be estimated by multiple linear regression formula, deduced from relationship between rice quality components mentioned above and eating quality of cooked rice, with high Probability of determination. The ${\alpha}$ -amylose-iodine method was adopted for checking the varietal difference in retrogradation of cooked rice. The rice cultivars revealing the relatively slow retrogradation in aged cooked rice were Ilpumbyeo, Chucheongbyeo, Sasanishiki, Jinbubyeo and Koshihikari. A Tongil-type rice, Taebaegbyeo, and a japonica cultivar, Seomjinbyeo, shelved the relatively fast deterioration of cooked rice. Generally, the better rice cultivars in eating quality of cooked rice showed less retrogiadation and much sponginess in cooled cooked rice. Also, the rice varieties exhibiting less retrogradation in cooled cooked rice revealed higher hot viscosity and lower cool viscosity of rice flour in amylogram. The sponginess of cooled cooked rice was closely associated with magnesium content and volume expansion of cooked rice. The hardness-changed ratio of cooked rice by cooling was negatively correlated with solids amount extracted during boiling and volume expansion of cooked rice. The major physicochemical properties of rice grain closely related to the palatability of cooked rice may be directly or indirectly associated with the retrogradation characteristics of cooked rice. The softer gel consistency and lower amylose content in milled rice revealed the higher ratio of popped rice and larger bulk density of popping. The stronger hardness of rice grain showed relatively higher ratio of popping and the more chalky or less translucent rice exhibited the lower ratio of intact popped brown rice. The potassium and magnesium contents of milled rice were negatively associated with gross score of noodle making mixed with wheat flour in half and the better rice for noodle making revealed relatively less amount of solid extraction during boiling. The more volume expansion of batters for making brown rice bread resulted the better loaf formation and more springiness in rice bread. The higher protein rices produced relatively the more moist white rice bread. The springiness of rice bread was also significantly correlated with high amylose content and hard gel consistency. The completely chalky and large gram rices showed better suitability for fermentation and brewing. Our breeding efforts on rice quality improvement for the future should focus on enhancement of palatability of cooked rice and marketing qualify as well as the diversification in morphological and physicochemical characteristics of rice grain for various value-added rice food processings.

• Journal of Animal Science and Technology
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• v.55 no.1
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• pp.51-59
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• 2013

This study was conducted to investigate the dietary effect of total mixed rations (TMR) containing brewers grain, soybean curd and rice straw, respectively, on growth performance and carcass characteristics of Hanwoo steers. Twenty four Hanwoo steers (average body weight 168 kg) in 6 months age were randomly allocated to 4 experimental groups, which contained 6 animals per group during 22-months feeding trial. The treatment was composed of the group fed concentrate and rice straw separately (T1), the group fed TMR containing brewers grain (T2), the group fed TMR containing soybean curd (T3) and the group fed TMR containing rice straw (T4). Body weight (BW) was not different among treatment groups during the growing and middle fattening period. However, it was significantly greater in T4 group than in T2 group on the final BW (p<0.05). Average daily gain was significantly greater in TMR groups compared to T1 group on the growing and late fattening (p<0.05). However, it was not different in total average. Dry matter intake tended to be increased in TMR groups. The feed conversion ratio was significantly lower in T4 group compare to T2 group (p<0.05). According to the yield traits, carcass weight of T1, T2, T3 and T4 were 389.0, 368.4, 387.5 and 384.3 kg, respectively. The back fat thickness, rib-eye area, and yield index were not different among the groups. Meat color, fat color, texture and maturity were not significantly different among groups. However, marbling score and appearance rate of meat quality grade of over $1^+$ were greater in T2 and T3 groups compare to other groups. Therefore, these results indicated that TMR with brewers grain and soybean curd may be ameliorated the growth performance and carcass characteristics of Hanwoo steers.